Journal articles on the topic 'Weather induced rail temperature'
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1
Caprio, J. M., and H. A. Quamme. "Influence of weather on apricot, peach and sweet cherry production in the Okanagan Valley of British Columbia." Canadian Journal of Plant Science 86, no. 1 (January 1, 2006): 259–67. http://dx.doi.org/10.4141/p05-032.
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An iterative χ2 method that generates indices of association was used to determine daily weather occurrences associated with annual variations in peach (Prunus persica Batch.), apricot (Prunus armeniaca L.), and sweet cherry production (Prunus avium L.) in the Okanagan Valley of British Columbia over a 72 yr period, 1920–1991. During September and early October of the pre-harvest year, warm daytime temperatures favoured apricot (≥ 26°C) and sweet cherry production (≥ 19°C), probably because this promoted flower bud development. High daytime temperatures (≥ 27°C) were detrimental to apricot production in August of the pre-harvest year. During the pre-harvest year, peach production was only weakly associated with daytime temperature. Precipitation adversely affected peach and sweet cherry production in the preharvest year indirectly by associated lower temperatures or directly by enhanced disease infection. The main climatic factor limiting production of these crops was low temperatures from November to February (critical value range, ≥ -13 to ≥ -24°C, nighttime temperature) that cause winter injury. Precipitation during this period, usually snowfall, mostly favoured production. Poor production years were also associated with low nighttime temperatures (≤ -2 to -5°C) in spring at the time the flowers are prone to frost injury. During the bloom period warm temperatures (≥16°C, daytime temperature) favoured Prunus production, probably because of the temperature requirements for good pollination and flower set. Rainfall during fruit development and harvest of sweet cherry reduced production because of rain-induced cracking. Daytime temperatures were detrimental to production of apricot (≥ 31°C) and sweet cherry (≥ 33°C to ≥ 37° C) during harvest. The anticipated climate change appears to favour Prunus production in the Okanagan Valley, except for increased rainfall on sweet cherry production. Key words: Prunus persica Batch., Prunus armeniaca L., Prunus avium L., tree fruit, climate, heat stress, spring frost, winter injury
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Byun, Do-Seong, Yang-Ki Cho, In-Ae Huh, and Deirdre E. Hart. "Runoff-induced vertical thermal dynamics in a canyon-shaped reservoir during the summer monsoon." Marine and Freshwater Research 56, no. 7 (2005): 959. http://dx.doi.org/10.1071/mf04285.
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During the summer rainy season, double thermoclines were observed in a small canyon-shaped reservoir. The physical processes leading to thermocline evolution are examined from the vertical temperature profile observed along the reservoir before and after rain. Observations show that their evolution is related to the inflow of runoff, which is colder than the reservoir surface water and post-rain fair-weather conditions. Tongue-like distributions of turbidity, conductivity and nutrient concentrations downstream from the headwater clearly reveal the presence of runoff-induced intermediate inflows. In addition to supplying nutrients, the inflow provides the oxygen-deficient intermediate layer with a rich supply of dissolved oxygen. Concurrently, in the upper part of the reservoir runoff-induced inflows may drive the oxygen-deficient bottom water to shift downstream along the layer beneath the runoff-induced inflow. The water mass between the two thermoclines may operate as a source of nutrients for algal development in early autumn when the upper thermocline is destroyed by the convective overturn owing to the surface cooling.
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Tardif, Robert, and Roy M. Rasmussen. "Process-Oriented Analysis of Environmental Conditions Associated with Precipitation Fog Events in the New York City Region." Journal of Applied Meteorology and Climatology 47, no. 6 (June 1, 2008): 1681–703. http://dx.doi.org/10.1175/2007jamc1734.1.
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Abstract An analysis of the environmental conditions associated with precipitation fog events is presented using 20 yr of historical observations taken in a region centered on New York, New York. The objective is to determine the preferred weather scenarios and identify physical processes influencing the formation of fog during precipitation. Salient synoptic-scale features are identified using NCEP–NCAR reanalyses. Local environmental parameters, such as wind speed and direction, temperature, and humidity, are analyzed using surface observations, while the vertical structure of the lower atmosphere is examined using available rawinsonde data. The analysis reveals that precipitation fog mostly occurs as a result of the gradual lowering of cloud bases as continuous light rain or light drizzle is observed. Such scenarios occur under various synoptic weather patterns in areas characterized by large-scale uplift, differential temperature advection, and positive moisture advection. Precipitation fog onset typically occurs with winds from the northeast at inland locations and onshore flow at coastal locations, with flows from the south to southwest aloft. A majority of the cases showed the presence of a sharp low-level temperature inversion resulting from differential temperature advection or through the interaction of warm air flowing over a cold surface in onshore flow conditions. This suggests a common scenario of fog formation under moistening conditions resulting from precipitation evaporating into colder air near the surface. A smaller number of events formed with cooling of the near-saturated or saturated air. Evidence is also presented of the possible role of shear-induced turbulent mixing in the production of supersaturation and fog formation during precipitation.
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Wang, Xuemei, Jingbiao Liao, Jian Zhang, Chong Shen, Weihua Chen, Beicheng Xia, and Tijian Wang. "A Numeric Study of Regional Climate Change Induced by Urban Expansion in the Pearl River Delta, China." Journal of Applied Meteorology and Climatology 53, no. 2 (February 2014): 346–62. http://dx.doi.org/10.1175/jamc-d-13-054.1.
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AbstractThe Pearl River Delta region has experienced rapid urbanization and economic development during the past 20 years. To investigate the impacts of urbanization on regional climate, the Advanced Research core of the Weather Research and Forecasting (ARW-WRF) model is used to conduct a pair of 1-yr simulations with two different representations of urbanization. Results show that the reduction in vegetated and irrigated cropland due to urban expansion significantly modifies the near-surface temperature, humidity, wind speed, and regional precipitation, which are obtained based on the significance t test of the differences between two simulations with different urbanization representations at the 95% level. Urbanization causes the mean 2-m temperature over urbanized areas to increase in all seasons (from spring to winter: 1.7° ± 0.7°C, 1.4° ± 0.3°C, 1.3° ± 0.3°, and 0.9° ± 0.4°C, respectively) and the urban diurnal temperature range decreases in three seasons and increases in one (from spring to winter: −0.5° ± 0.3°C, +0.6° ± 0.3°C, −0.4° ± 0.2°C, and −0.8° ± 0.2°C, respectively). Urbanization reduces near-surface water vapor (1.5 g kg−1 in summer and 0.4 g kg−1 in winter), 10-m wind speed (37% independent of season), and annual total precipitation days (approximately 6–14 days). However, the total rainfall amount increases by approximately 30%, since the decrease in the number of days with light rain (8–12) is overcome by the increase in the number of days of heavy or extreme rain (3–6), suggesting that urbanization induces more heavy rain events over the urban areas. Overall, the effect of urbanization on regional climate in the Pearl River Delta is found to be significant and must be considered in any broader regional climate assessment.
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Huang, Jingfeng, Chidong Zhang, and Joseph M. Prospero. "Aerosol-Induced Large-Scale Variability in Precipitation over the Tropical Atlantic." Journal of Climate 22, no. 19 (October 1, 2009): 4970–88. http://dx.doi.org/10.1175/2009jcli2531.1.
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Abstract Multiyear satellite observations are used to document a relationship between the large-scale variability in precipitation over the tropical Atlantic and aerosol traced to African sources. During boreal winter and spring there is a significant reduction in precipitation south of the Atlantic marine intertropical convergence zone (ITCZ) during months when aerosol concentrations are anomalously high over a large domain of the tropical Atlantic Ocean. This reduction cannot be linearly attributed to known climate factors such as El Niño–Southern Oscillation, the North Atlantic Oscillation, and zonal and meridional modes of tropical Atlantic sea surface temperature or to meteorological factors such as water vapor. The fractional variance in precipitation related to aerosol is about 12% of the total interannual variance, which is of the same order of magnitude as that related to each of the known climate and weather factors. A backward trajectory analysis confirms the African origin of aerosols that directly affect the changes in precipitation. The reduction in mean precipitation mainly comes from decreases in moderate rain rates (10–20 mm day−1), while light rain (<10 mm day−1) can fluctuate in the opposite direction. The results cannot be readily explained in terms of wet deposition or uncertainties in satellite retrievals, and suggest that the observations demonstrate clearly identifiable effects of African aerosol on large-scale variability in precipitation in the tropical Atlantic region.
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Greco, Aldo, Davide Luciano De Luca, and Elenio Avolio. "Heavy Precipitation Systems in Calabria Region (Southern Italy): High-Resolution Observed Rainfall and Large-Scale Atmospheric Pattern Analysis." Water 12, no. 5 (May 21, 2020): 1468. http://dx.doi.org/10.3390/w12051468.
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An in-depth analysis of historical heavy rainfall fields clearly constitutes an important aspect in many related topics: as examples, mesoscale models for early warning systems and the definition of design event scenarios can be improved, with the consequent upgrading in the prediction of induced phenomena (mainly floods and landslides) into specific areas of interest. With this goal, in this work the authors focused on Calabria region (southern Italy) and classified the main precipitation systems through the analysis of selected heavy rainfall events from high resolution rain gauge network time series. Moreover, the authors investigated the relationships among the selected events and the main synoptic atmospheric patterns derived by the European Centre for Medium-Range Weather Forecasts (ECMWF) ERA5 Reanalysis dataset, in order to assess the possible large-scale scenarios which can induce heavy rainfall events in the study area. The obtained results highlighted: (i) the importance of areal reduction factors, rainfall intensities and amounts in order to discriminate the investigated precipitations systems for the study area; (ii) the crucial role played by the position of the averaged low-pressure areas over the Mediterranean for the synoptic systems, and by low-level temperature for the convective systems.
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Chubb, Thomas, Michael J. Manton, Steven T. Siems, Andrew D. Peace, and Shane P. Bilish. "Estimation of Wind-Induced Losses from a Precipitation Gauge Network in the Australian Snowy Mountains." Journal of Hydrometeorology 16, no. 6 (November 17, 2015): 2619–38. http://dx.doi.org/10.1175/jhm-d-14-0216.1.
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Abstract Wind-induced losses, or undercatch, can have a substantial impact on precipitation gauge observations, especially in alpine environments that receive a substantial amount of frozen precipitation and may be exposed to high winds. A network of NOAH II all-weather gauges installed in the Snowy Mountains since 2006 provides an opportunity to evaluate the magnitude of undercatch in an Australian alpine environment. Data from two intercomparison sites were used with NOAH II gauges with different configurations of wind fences installed: unfenced, WMO standard double fence intercomparison reference (full DFIR) fences, and an experimental half-sized double fence (half DFIR). It was found that average ambient temperature over 6-h periods was sufficient to classify the precipitation phase as snow, mixed precipitation, or rain in a statistically robust way. Empirical catch ratio relationships (i.e., the quotient of observations from two gauges), based on wind speed, ambient temperature, and measured precipitation amount, were established for snow and mixed precipitation. An adjustment scheme to correct the unfenced NOAH II gauge data using the catch ratio relationships was cross validated with independent data from two additional sites, as well as from the intercomparison sites themselves. The adjustment scheme was applied to the observed precipitation amounts at the other sites with unfenced NOAH II gauges. In the worst-case scenario, it was found that the observed precipitation amount would need to be increased by 52% to match what would have been recorded had adequate shielding been installed. However, gauges that were naturally well protected, and those below about 1400 m, required very little adjustment. Spatial analysis showed that the average seasonal undercatch was between 6% and 15% for gauges above 1000 m MSL.
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Winchester, Chevelle R., Priya Batta, Dhillon Davinder, and Alan R. Hirsch. "97 My Inner Blizzard: Effect of Weather on Multiple Sclerosis Exacerbation." CNS Spectrums 24, no. 1 (February 2019): 223. http://dx.doi.org/10.1017/s1092852919000890.
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AbstractStudy ObjectiveExacerbation of Multiple Sclerosis (MS) symptoms prior to weather change has not heretofore been described.MethodsCase Study: A 60 year old right handed female with lifelong anxiety and four years of depression presented with a 20 year history of MS manifested by bilateral lower extremity pain and weakness and urinary incontinence. Since the onset, she observed that approaching storms or weather changes cause her symptoms to worsen. This manifests one day prior to the meteorological shifts of rain or snow. This occurs whether she is at home or on vacation and unlike the weatherman, “she is never wrong.” The aggravation of symptomatology would consist of worsening leg pain and weakness of both lower extremities so that her functional status changes from using a cane to a wheelchair. These symptoms begin one day prior to the storm and gradually worsen to the point of maximum intensity as the storm arrives. The baseline pain is usually 5/10 in severity but with the storm it increases to 8/10. The pain, which progressively worsens as the storm advances, is a vice-like numbness in her shins and spasm in her legs. The pain and weakness will persist for as long as the storm lasts. The pain diminishes and the motor symptoms improve six hours after the storm is over. She can differentiate approaching snow or rain such that snow causes more intense symptoms. She denies change in symptomatology on airplanes or when she is present at high altitude such as Las Vegas or Colorado. She also affirms that her symptoms are worse when she is in a hot tub and better in a cold-water bath. She reports that there is a family history of similar ability to predict the weather in a cousin and nephew, both who also suffer from MS.ResultsAbnormalities in Neurological Examination: BP 159/115. Pulse 100. Mental Status Examination: disheveled. Depressed mood with congruent affect. Short-term memory: 5 digits forwards, 2 digits backwards. Recent memory: able to recall none of 4 objects in 3minutes without improvement with reinforcement. Unable to interpret similarities or proverbs. Poor ability to calculate. Reflexes: 3+ bilateral lower extremities. Clock Drawing Test: 1 (abnormal).ConclusionsUhthoff’s phenomena (hot bath test) is well described in MS (Humm, 2004), however the worsening of symptoms prior to weather change has not been reported. Possible mechanisms include meteorological induced anxiety and depression with associated exacerbation (Ackerman, 1998). Other possible mechanisms include misattribution, selective recall, or a misreporting due to psychological needs for acceptance by examiner, similar to the Hawthorne effect (observer effect) (Adair, 1984). With the approaching storms there could be a change in internal temperature, which then preferentially affects areas of demyelination (Kudo, 2014). It is worth querying those with epoch associated neurological disorders as to linkage with meteorological events.
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Kolusu, S. R., J. H. Marsham, J. Mulcahy, B. Johnson, C. Dunning, M. Bush, and D. V. Spracklen. "Impacts of Amazonia biomass burning aerosols assessed from short-range weather forecasts." Atmospheric Chemistry and Physics Discussions 15, no. 13 (July 10, 2015): 18883–919. http://dx.doi.org/10.5194/acpd-15-18883-2015.
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Abstract. The direct radiative impacts of Biomass Burning Aerosols (BBA) on meteorology are investigated using short-range forecasts from the Met Office Unified Model (MetUM) over South America during the South American Biomass Burning Analysis (SAMBBA). The impacts are evaluated using a set of three simulations: (i) no aerosols, (ii) with monthly mean aerosol climatologies and (iii) with prognostic aerosols modelled using the Coupled Large-scale Aerosol Simulator for Studies in Climate (CLASSIC) scheme. Comparison with observations show that the prognostic CLASSIC scheme provides the best representation of BBA. The impacts of BBA are quantified over central and southern Amazonia from the first and second day of two day forecasts during 14 September–03 October 2012. On average, during the first day of the forecast, including prognostic BBA reduces the clear-sky net radiation at the surface by 15 ± 1 W m−2, and reduces net TOA radiation by 8 ± 1 W m−2, with a direct atmospheric warming of 7 ± 1 W m−2. BBA-induced reductions in all-sky radiation are smaller in magnitude: 9.0 ± 1 W m−2 at the surface and 4.0 ± 1 W m−2 at TOA. In this modelling study the BBA therefore exert an overall cooling influence on the Earth–atmosphere system, although some levels of the atmosphere are directly warmed by the absorption of solar radiation. Due to the reduction of net radiative flux at the surface the mean 2 m air temperature is reduced by around 0.1 ± 0.02 °C. The BBA also cools the boundary layer (BL) but warms air above by around 0.2 °C due to the absorption of shortwave radiation. The overall impact is to reduce the BL depth by around 19 ± 8 m. These differences in heating lead to a more anticyclonic circulation at 700 hPa, with winds changing by around 0.6 m s−1. Inclusion of BBA in the MetUM significantly improves forecasts of temperature and relative humidity, but effects were small compared with model error and differences between effects from climatological and prognostic BBA were not significant. Locally, on a 150 km scale, changes in precipitation reach around 4 mm day−1 due to changes in the location of convection. Over Amazonia, including BBA in the simulation led to fewer rain events that were more intense. This change may be linked to the BBA changing the vertical profile of stability in the lower atmosphere. The localised changes in rainfall tend to average out to give a 5 % (0.06 mm day−1) decrease in total precipitation over the Amazonian region (except on day 2 with prognostic BBA). The change in water budget from BBA is, however, dominated by decreased evapotranspiration from the reduced net surface fluxes (0.2 to 0.3 mm day−1), since this term is larger than the corresponding changes in precipitation and water vapour convergence.
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Mbokodo, Innocent L., Mary-Jane M. Bopape, Thando Ndarana, Sifiso M. S. Mbatha, Tshimbiluni P. Muofhe, Mukovhe V. Singo, Nkosinathi G. Xulu, Tumelo Mohomi, Kingsley K. Ayisi, and Hector Chikoore. "Heatwave Variability and Structure in South Africa during Summer Drought." Climate 11, no. 2 (February 5, 2023): 38. http://dx.doi.org/10.3390/cli11020038.
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Pronounced subsidence leading to summer drought over southern Africa causes warmer than average surface air temperatures or even heatwave (HW) conditions. We investigated the occurrence of HWs during the summer drought over South Africa based on station data and the ECMWF ERA5 reanalyses. Temperature observations from the South African Weather Service were analyzed for seasonality and long-term trends (1981–2020) as background to the occurrence and variability of HWs. We focused on three severe El Niño Southern Oscillation (ENSO)-induced drought seasons, i.e., 1982/83, 1991/92, and 2015/16, to investigate HW characteristics. While 1997/98 was among the strongest El Niño seasons, the impacts were not as severe because it coincided with an intense Angola low, which allowed for rain-bearing cloud bands to form. Results showed that the hottest months were spread across the austral summer season from December to February. Regions experiencing high mean maximum temperatures and high HW frequencies exhibited a strong ENSO signal, with record HWs occurring during 2015/16. The establishment and persistence of a middle-level high-pressure system over Botswana/Namibia (Botswana High) appears to trigger the longest-lasting HWs during drought seasons. The Botswana high is usually coupled with a near-surface continental heat low and/or tropical warm air advection towards the affected region. It was also found that intense ENSO-induced drought events coincided with high HW frequency over South Africa, such as during 1982/83, 1991/92, and the recent 2015/16 events. The results of this study contribute to understanding drought and heat wave dynamics in a region experiencing rapid warming as a result of climate change.
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Łupikasza, E. B., and K. Cielecka-Nowak. "Changing Probabilities of Days with Snow and Rain in the Atlantic Sector of the Arctic under the Current Warming Trend." Journal of Climate 33, no. 7 (April 1, 2020): 2509–32. http://dx.doi.org/10.1175/jcli-d-19-0384.1.
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AbstractTrends in the probabilities of days with liquid, solid, and mixed precipitation are discussed on annual and intra-annual scales along with their relationship to air temperature in the Atlantic sector of the Arctic. Data on weather phenomena were used to identify precipitation phases. The data cover various periods but all series extend to 2017. Trends in the annual air temperature and probability of precipitation phases for various long-term periods are discussed and differences in the mean air temperature and probability of precipitation phases between 1979–97 (insignificant warming) and 1999–2017 (significant warming) on an intra-annual scale. In the studied region, the precipitation phases were sensitive to warming and atmospheric circulation to various degrees, depending on the phase, mean climate, month, and local conditions. The probability of days with rainfall increased (by +1% to +3% per decade), whereas the probability of days with snowfall decreased (by −1.5% to −2.4% per decade). The increasing trends in the probability of rainy days at all stations and decreasing trends in the probability of snowy days in the southern part of the region were warming induced. The most significant and widespread trends in snowy and rainy days were found in September. The probability of days with mixed precipitation exhibited no trends due to an inverse reaction to warming in the warmer and colder parts of the year. Temporal variability in the probability of precipitation phases was significantly linked to three teleconnection patterns playing a role in various parts of the year.
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Kolusu, S. R., J. H. Marsham, J. Mulcahy, B. Johnson, C. Dunning, M. Bush, and D. V. Spracklen. "Impacts of Amazonia biomass burning aerosols assessed from short-range weather forecasts." Atmospheric Chemistry and Physics 15, no. 21 (November 5, 2015): 12251–66. http://dx.doi.org/10.5194/acp-15-12251-2015.
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Abstract. The direct radiative impacts of biomass burning aerosols (BBA) on meteorology are investigated using short-range forecasts from the Met Office Unified Model (MetUM) over South America during the South American Biomass Burning Analysis (SAMBBA). The impacts are evaluated using a set of three simulations: (i) no aerosols, (ii) with monthly mean aerosol climatologies and (iii) with prognostic aerosols modelled using the Coupled Large-scale Aerosol Simulator for Studies In Climate (CLASSIC) scheme. Comparison with observations show that the prognostic CLASSIC scheme provides the best representation of BBA. The impacts of BBA are quantified over central and southern Amazonia from the first and second day of 2-day forecasts during 14 September–3 October 2012. On average, during the first day of the forecast, including prognostic BBA reduces the clear-sky net radiation at the surface by 15 ± 1 W m−2 and reduces net top-of-atmosphere (TOA) radiation by 8 ± 1 W m−2, with a direct atmospheric warming of 7 ± 1 W m−2. BBA-induced reductions in all-sky radiation are smaller in magnitude: 9.0 ± 1 W m−2 at the surface and 4.0 ± 1 W m−2 at TOA. In this modelling study the BBA therefore exert an overall cooling influence on the Earth–atmosphere system, although some levels of the atmosphere are directly warmed by the absorption of solar radiation. Due to the reduction of net radiative flux at the surface, the mean 2 m air temperature is reduced by around 0.1 ± 0.02 °C. The BBA also cools the boundary layer (BL) but warms air above by around 0.2 °C due to the absorption of shortwave radiation. The overall impact is to reduce the BL depth by around 19 ± 8 m. These differences in heating lead to a more anticyclonic circulation at 700 hPa, with winds changing by around 0.6 m s−1. Inclusion of climatological or prognostic BBA in the MetUM makes a small but significant improvement in forecasts of temperature and relative humidity, but improvements were small compare with model error and the relative increase in forecast skill from the prognostic aerosol simulation over the aerosol climatology was also small. Locally, on a 150 km scale, changes in precipitation reach around 4 mm day−1 due to changes in the location of convection. Over Amazonia, including BBA in the simulation led to fewer rain events that were more intense. This change may be linked to the BBA changing the vertical profile of stability in the lower atmosphere. The localised changes in rainfall tend to average out to give a 5 % (0.06 mm day−1) decrease in total precipitation over the Amazonian region (except on day 2 with prognostic BBA). The change in water budget from BBA is, however, dominated by decreased evapotranspiration from the reduced net surface fluxes (0.2 to 0.3 mm day−1), since this term is larger than the corresponding changes in precipitation and water vapour convergence.
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Roy, A., D. Kolady, B. Paudel, A. Yumnam, N. Mridha, D. Chakraborty, and N. U. Singh. "Recent trends and impacts of climate change in North-Eastern region of India-A review." Journal of Environmental Biology 42, no. 6 (November 15, 2021): 1415–24. http://dx.doi.org/10.22438/jeb/42/6/mrn-1701.
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The economy of North-Eastern (NE) region of India predominantly depends on farming, where only 12% of geographical area is available for cultivation out of which more than 85% is rain fed. Climate change has become a major concern in agriculture today, as farmers in many regions are struggling to cope with changing temperatures and rainfall pattern. Moreover, extreme weather situations like droughts, floods, heat and cold waves pose serious threat to food security, especially for small and marginal farmers. This review paper discusses the climate change in North-Eastern India based on the available climatic data from various published sources. Most of the analysis was performed on time series meteorological data recorded at different locations across the states of North-Eastern India namely, Assam, Arunachal Pradesh, Sikkim, Nagaland, Meghalaya, Manipur, Mizoram and Tripura. The increase in mean annual maximum temperature varied from 0.1°C per decade in Imphal (Manipur) to about 1.4°C per decade in Jharnapani (Nagaland). The changes were significant for all the states, except Sikkim. This region is one of the highest rainfall receiving regions of the world, but during February-March it faces water scarcity. The rainfall is projected to increase in 57 districts out of 78 districts, with some districts expected to experience almost 25% more rainfall than usual. The North-Eastern region of India has experienced notable changes in the pattern of major climatic variables such as rainfall and temperature. Average temperatures are projected to increase in almost all the districts of the region while annual rainfall is also reported to increase in almost 3/4th of the districts. The climate-induced natural disasters like drought, flood and hailstorms are the major threats of climate change and the incidence of these natural disasters are increasing in the recent years over the region.
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Van Nguyen, Hiep, Yi-Leng Chen, and Francis Fujioka. "Numerical Simulations of Island Effects on Airflow and Weather during the Summer over the Island of Oahu." Monthly Weather Review 138, no. 6 (June 1, 2010): 2253–80. http://dx.doi.org/10.1175/2009mwr3203.1.
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Abstract The high-resolution (1.5 km) nonhydrostatic fifth-generation Pennsylvania State University–National Center for Atmospheric Research (PSU–NCAR) Mesoscale Model (MM5) and an advanced land surface model (LSM) are used to study the island-induced airflow and weather for the island of Oahu, Hawaii, under summer trade wind conditions. Despite Oahu’s relatively small area (1536 km2), there are considerable spatial variations in horizontal distribution of thermodynamic fields related to terrain, airflow, rain, cloud, and ground cover. The largest diurnal variations in temperature and moisture occur in the lee sides of mountains, especially along the western leeside coast. The island-scale surface airflow is also significantly affected by terrain and land surface forcing. The downslope winds above the leeside slopes of both the Ko’olau and Waianae Mountains are simulated with significant diurnal variations with the strongest downslope winds just before sunrise. The timing of diurnal rainfall maxima over the Ko’olau Mountains is closely related to vertical motions. The early morning rainfall maximum on the windward side is caused by anomalous rising motion due to significant flow deceleration when the land surface is the coolest. The evening rainfall maximum after sunset is related to anomalous orographic lifting due to stronger winds aloft. In the early afternoon, winds aloft are relatively weak with a relatively high level of free convection (LFC) because of vertical mixing. As a result, the rainfall over the Ko’olau Mountains exhibits an afternoon minimum. The westerly reversed flow off the western leeside coast in the afternoon is mainly thermally driven and related to land surface heating superimposed by latent heat release of persistent orographic precipitation over the Ko’olau Mountains. Rainfall along the western leeside slopes has a late afternoon maximum due to the development of the onshore/upslope flow.
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Abdullahi, Bulle, Joshua Mutiso, Fredrick Maloba, John Macharia, Mark Riongoita, and Michael Gicheru. "Climate Change and Environmental Influence on Prevalence of Visceral Leishmaniasis in West Pokot County, Kenya." Journal of Tropical Medicine 2022 (September 20, 2022): 1–6. http://dx.doi.org/10.1155/2022/1441576.
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Kala-azar is a parasitic disease caused by Leishmania species transmitted by sand fly. In Kenya, kala-azar is endemic in thirty subcounties spread over in eleven counties in the arid zones. Climate change-influenced seasonal weather variability and environmental alterations remain important determinants of many vector-borne diseases. The present study focused on climate change and environmental influence on kala-azar in West Pokot. A descriptive cross-sectional and retrospective research design was adapted. Study area was purposively selected. Locations were randomly selected, and households were systematically selected. Three hundred sixty-three household questionnaires, eleven key informant interviews, and five focus group discussions were undertaken. Secondary data were obtained from Kacheliba subcounty hospital records. Statistical Package for the Social Sciences version 24 was used to analyze quantitative data while qualitative data were analyzed to establish connection for interpretation. Kala-azar cases have been on the rise on aggregate and surge towards the end of dry season and just after the rains. Significant environmental factors included the presence of seasonal rain water pathways and rock piles around houses (AOR = 4.7; 95% CI = (2.3-9.6), p < 0.05 ), presence of acacia trees in and around homesteads (AOR = 8.5; 95% CI = (2.5-28.6), p < 0.05 ), presence of anthills around the homesteads (AOR = 5.2; 95% CI = (1.2-23.4), p < 0.05 ), and presence of animal shed within compound (AOR = 2.8; 95% CI = (0.96-8), p < 0.05 ). Climate change-induced seasonal weather variability, increased temperature and reduced precipitation as well as environmental alterations influence kala-azar occurrence in West Pokot. Community sensitization on disease prevalence, clearing of vector predilection sites, and improving community environmental risk perception are imperative to promote prevention.
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Shi, Xiaoming, and Dale R. Durran. "Estimating the Response of Extreme Precipitation over Midlatitude Mountains to Global Warming." Journal of Climate 28, no. 10 (May 12, 2015): 4246–62. http://dx.doi.org/10.1175/jcli-d-14-00750.1.
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Abstract Global warming–induced changes in extreme orographic precipitation are investigated using a hierarchy of models: a global climate model, a limited-area weather forecast model, and a linear mountain wave model. The authors consider precipitation changes over an idealized north–south midlatitude mountain barrier at the western margin of an otherwise flat continent. The intensities of the extreme events on the western slopes increase by approximately 4% K−1 of surface warming, close to the “thermodynamic” sensitivity of vertically integrated condensation in those events due to temperature variations when vertical motions stay constant. In contrast, the intensities of extreme events on the eastern mountain slopes increase at about 6% K−1. This higher sensitivity is due to enhanced ascent during the eastern-slope events, which can be explained in terms of linear mountain wave theory as arising from global warming–induced changes in the upper-tropospheric static stability and the tropopause level. Similar changes to these two parameters also occur for the western-slope events, but the cross-mountain flow is much stronger in those events; as a consequence, linear theory predicts no increase in the western-slope vertical velocities. Extreme western-slope events tend to occur in winter, whereas those on the eastern side are most common in summer. Doubling CO2 not only increases the precipitation, but during extreme western slope events it shifts much of the precipitation from snow to rain, potentially increasing the risk of heavy runoff and flooding.
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Guo, Yongqing, Xiaoyuan Wang, Qing Xu, Shanliang Liu, Shijie Liu, and Junyan Han. "Weather Impact on Passenger Flow of Rail Transit Lines." Civil Engineering Journal 6, no. 2 (February 1, 2020): 276–84. http://dx.doi.org/10.28991/cej-2020-03091470.
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Passenger flow prediction is important for the planning, design and decision-making of urban rail transit lines. Weather is an important factor that affects the passenger flow of rail transit line by changing the travel mode choice of urban residents. A number of previous researches focused on analyzing the effects of weather (e.g. rain, snow, and temperature) on public transport ridership, but the effects on rail transit line yet remain largely unexplored This study aims to explore the influence of weather on ridership of urban rail transit lines, taking Chengdu rail transit line 1 and line 2 as examples. Linear regression method was used to develop models for estimating the daily passenger flow of different rail transit lines under different weather conditions. The results show that for Chengdu rail transit line 1, the daily ridership rate of rail transit increases with increasing temperature. While, for Chengdu rail transit line 2, the daily ridership rate of rail transit decreases with increasing wind power. The research findings can provide effective strategies to rail transit operators to deal with the fluctuation in daily passenger flow.
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Wang, Xiaoyuan, Yongqing Guo, Chenglin Bai, Shanliang Liu, Shijie Liu, and Junyan Han. "The Effects of Weather on Passenger Flow of Urban Rail Transit." Civil Engineering Journal 6, no. 1 (January 1, 2020): 11–20. http://dx.doi.org/10.28991/cej-2020-03091449.
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Predicting passenger flow on urban rail transit is important for the planning, design and decision-making of rail transit. Weather is an important factor that affects the passenger flow of rail transit by changing the travel mode choice of urban residents. This study aims to explore the influence of weather on urban rail transit ridership, taking four cities in China as examples, Beijing, Shanghai, Guangzhou and Chengdu. To determine the weather effect on daily ridership rate, the three models were proposed with different combinations of the factors of temperature and weather type, using linear regression method. The large quantities of data were applied to validate the developed models. The results show that in Guangzhou, the daily ridership rate of rail transit increases with increasing temperature. In Chengdu, the ridership rate increases in rainy days compared to sunny days. While, in Beijing and Shanghai, the ridership rate increases in light rainfall and heavy rainfall (except moderate rainfall) compared to sunny days. The research findings are important to understand the impact of weather on passenger flow of urban rail transit. The findings can provide effective strategies to rail transit operators to deal with the fluctuation in daily passenger flow.
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Wolff, M. A., K. Isaksen, A. Petersen-Øverleir, K. Ødemark, T. Reitan, and R. Brækkan. "Derivation of a new continuous adjustment function for correcting wind-induced loss of solid precipitation: results of a Norwegian field study." Hydrology and Earth System Sciences 19, no. 2 (February 20, 2015): 951–67. http://dx.doi.org/10.5194/hess-19-951-2015.
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Abstract. Precipitation measurements exhibit large cold-season biases due to under-catch in windy conditions. These uncertainties affect water balance calculations, snowpack monitoring and calibration of remote sensing algorithms and land surface models. More accurate data would improve the ability to predict future changes in water resources and mountain hazards in snow-dominated regions. In 2010, a comprehensive test site for precipitation measurements was established on a mountain plateau in southern Norway. Automatic precipitation gauge data are compared with data from a precipitation gauge in a Double Fence Intercomparison Reference (DFIR) wind shield construction which serves as the reference. A large number of other sensors are provided supporting data for relevant meteorological parameters. In this paper, data from three winters are used to study and determine the wind-induced under-catch of solid precipitation. Qualitative analyses and Bayesian statistics are used to evaluate and objectively choose the model that best describes the data. A continuous adjustment function and its uncertainty are derived for measurements of all types of winter precipitation (from rain to dry snow). A regression analysis does not reveal any significant misspecifications for the adjustment function, but shows that the chosen model does not describe the regression noise optimally. The adjustment function is operationally usable because it is based only on data available at standard automatic weather stations. The results show a non-linear relationship between under-catch and wind speed during winter precipitation events and there is a clear temperature dependency, mainly reflecting the precipitation type. The results allow, for the first time, derivation of an adjustment function based on measurements above 7 m s−1. This extended validity of the adjustment function shows a stabilization of the wind-induced precipitation loss for higher wind speeds.
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Wolff, M. A., K. Isaksen, A. Petersen-Øverleir, K. Ødemark, T. Reitan, and R. Brækkan. "Derivation of a new continuous adjustment function for correcting wind-induced loss of solid precipitation: results of a Norwegian field study." Hydrology and Earth System Sciences Discussions 11, no. 9 (September 1, 2014): 10043–84. http://dx.doi.org/10.5194/hessd-11-10043-2014.
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Abstract. Precipitation measurements exhibit large cold-season biases due to under-catch in windy conditions. These uncertainties affect water balance calculations, snowpack monitoring and calibrations of remote sensing algorithms and land surface models. More accurate data would improve the ability to predict future changes in water resources and mountain hazards in snow-dominated regions. In 2010, an extensive test-site for precipitation measurements was established at a mountain plateau in Southern Norway. Precipitation data of automatic gauges were compared with a precipitation gauge in a Double Fence Intercomparison Reference (DFIR) wind shield construction which served as the reference. Additionally, a large number of sensors were monitoring supportive meteorological parameters. In this paper, data from three winters were used to study and determine the wind-induced under-catch of solid precipitation. Qualitative analyses and Bayesian statistics were used to evaluate and objectively choose the model that is describing the data best. A continuous adjustment function and its uncertainty were derived for measurements of all types of winter precipitation (from rain to dry snow). A regression analysis did not reveal any significant misspecifications for the adjustment function, but showed that the chosen model uncertainty is slightly insufficient and can be further optimized. The adjustment function is operationally usable based only on data available at standard automatic weather stations. Our results show a non-linear relationship between under-catch and wind speed during winter precipitation events and there is a clear temperature dependency, mainly reflecting the precipitation type. The results allowed for the first time to derive an adjustment function with a data-tested validity beyond 7 m s−1 and proved a stabilisation of the wind-induced precipitation loss for higher wind speeds.
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Wang, Yueyang, Yanjun Wang, Yan Wang, Qin Ju, Junliang Jin, and Zhenxin Bao. "Projecting Changes in Rainfall Extremes for the Huai River Basin in the Context of 1.5 °C and 2 °C Global Warming." Atmosphere 13, no. 10 (October 18, 2022): 1708. http://dx.doi.org/10.3390/atmos13101708.
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It is indisputable that global warming has triggered more frequent extreme weather and in turn led to severe flood disasters. To understand the trend of extreme rainfall under 1.5 °C and 2 °C warming, we investigated the historical variation and future trends in extreme rainfall for the Huai River basin, which has frequently been hit by floods, using recorded meteorological data and a projection of five General Circulation Models in the Coupled Model Intercomparison Project 6. We used the years 1995–2014 as the baseline period to study the temporal and spatial changes in extreme rainfall under 1.5 °C and 2.0 °C warming scenarios. The results indicated that (1) temperatures in the Huai River basin have risen significantly from 1995 to 2014, but there are insignificant variation trends in annual precipitation (AP), intensive precipitation (R95P), maximum daily precipitation (Rx1d) and heavy rain days (Rr50) during the same time span. (2) From 2015 to 2100, both temperature and extreme rainfall indices show increase trends, with a higher rate of increase under a higher emission scenario. (3) Under the warming scenario of 1.5 °C, AP, R95P, Rx1d and Rr50 in the basin will likely increase by 4.6%, 5.7%, 6.2% and 13.4%, respectively, compared with that in the baseline period. Under the warming scenario of 2.0 °C, AP, R95P, Rx1d and Rr50 will probably increase by 7.3%, 7.4%, 10.9% and 19.0%, respectively. (4) Spatially, the changes in extreme rainfall indices under the warming scenarios of 1.5 °C and 2.0 °C generally tend to increase from north to south. Higher intensity extreme rainfall will likely extend to the whole of the Huai River basin. It is therefore essential to study adaptive measures to cope with flooding in the Huai River basin induced by the increase in future rainfall extremes.
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Hong, Sunguk, Cheoljeong Park, and Seongjin Cho. "A Rail-Temperature-Prediction Model Based on Machine Learning: Warning of Train-Speed Restrictions Using Weather Forecasting." Sensors 21, no. 13 (July 5, 2021): 4606. http://dx.doi.org/10.3390/s21134606.
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Predicting the rail temperature of a railway system is important for establishing a rail management plan against railway derailment caused by orbital buckling. The rail temperature, which is directly responsible for track buckling, is closely related to air temperature, which continuously increases due to global warming effects. Moreover, railway systems are increasingly installed with continuous welded rails (CWRs) to reduce train vibration and noise. Unfortunately, CWRs are prone to buckling. This study develops a reliable and highly accurate novel model that can predict rail temperature using a machine learning method. To predict rail temperature over the entire network with high-prediction performance, the weather effect and solar effect features are used. These features originate from the analysis of the thermal environment around the rail. Precisely, the presented model has a higher performance for predicting high rail temperature than other models. As a convenient structural health-monitoring application, the train-speed-limit alarm-map (TSLAM) was also proposed, which visually maps the predicted rail-temperature deviations over the entire network for railway safety officers. Combined with TSLAM, our rail-temperature prediction model is expected to improve track safety and train timeliness.
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Crotteau, Justin S., Annelise Z. Rue-Johns, and Jeffrey C. Barnard. "Effects on understory biomass and forage 8–10 years after precommercial thinning of Sitka spruce – western hemlock stands in southeast Alaska." Canadian Journal of Forest Research 50, no. 2 (February 2020): 215–25. http://dx.doi.org/10.1139/cjfr-2019-0268.
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In southeast Alaska, United States, multiple-use forest management objectives include both timber production and wildlife habitat. Following stand-replacing disturbances such as clear-cutting, Sitka spruce (Picea sitchensis (Bong.) Carrière) and western hemlock (Tsuga heterophylla (Raf.) Sarg.) naturally regenerate and competitively dominate resources, excluding understory biomass and biodiversity. Thinning may mitigate the effects of canopy closure and permit understory development, but evidence of the effect on understories 8–10 years after thinning is lacking. We report results 4–5 and 8–10 years after thinning experiments on the Tongass National Forest to demonstrate the effects of precommercial thinning (thinned versus control), stand age (15–25, 25–35, and 35–50 years), and weather on understory dynamics and Sitka black-tailed deer (Odocoileus hemionus sitkensis Merriam, 1898) forage availability. Stand density negatively affected understory biomass, whereas temperature and precipitation positively interacted to increase biomass. Thinning had an enduring effect on understories, with biomass at least twice as great in thinned versus unthinned stands through year 10. We identified compositional differences from thinning as stand age class increased. Deer forage responded similarly to biomass, but thinning-induced differences faded with increased winter snowfall scenarios, especially in older stands. This study aids the understanding of stand overstory and understory development following silvicultural treatments in the coastal temperate rain forest of Alaska and suggests management implications and applications for balancing objectives throughout the forest type.
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Wang, Huaibin, Xiao Xu, Zhihui Wang, Rui Cao, Bingqian Zheng, Siyu Song, Yurui Jiang, Qianyu Zhu, and Wanqin Yang. "Abnormal Litter Induced by Typhoon Disturbances Had Higher Rates of Mass Loss and Carbon Release than Physiological Litter in Coastal Subtropical Urban Forest Ecosystems." Forests 13, no. 11 (November 1, 2022): 1819. http://dx.doi.org/10.3390/f13111819.
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The decomposition of abnormal litter caused by extreme weather events might play an increasingly important role in carbon and nutrient cycling in forest ecosystems under climate change scenarios, which needs to be fully investigated. In August 2020, the abnormal foliar litter of the goldenrain tree (Koelreuteria bipinnata var. Integrifoliola), the camphor tree (Cinnamomum camphora), and the weeping willow (Salix babylonica) after Typhoon Hagupit disturbance were collected and incubated on the soil surface at the Plant Ecology Research Base at Taizhou University, which is located on the eastern coast of China. Simultaneously, the physiological foliar litter of these three trees collected in the spring litter peak was incubated at the same site. The abnormal litter had higher concentrations of carbon (C), nitrogen (N), and phosphorus (P) and lower concentrations of lignin and cellulose than the physiological litter. The accumulative mass loss rates of abnormal litter in the goldenrain tree, the camphor tree, and the weeping willow during the incubation period increased by 7.72%, 29.78%, and 21.76% in comparison with physiological litter, and the corresponding carbon release increased by 9.10%, 24.15% and 19.55%, respectively. The autumn litter peak period and plum-rain season had higher rates of litter mass loss and carbon release, while the winter nongrowing season had lower rates. Accumulative mass loss, accumulative carbon release, daily mass loss and the daily carbon release of foliar litter were significantly and positively correlated with temperature and initial P concentrations, and significantly and negatively correlated with the initial C/P ratio, lignin/N ratio, and lignin/P ratio (p < 0.05). Compared with the physiological litter, abnormal litter had higher initial substrate quality, which may be the most important factor contributing to their high rates of mass loss and carbon release. The results imply that increasing tropical cyclones under climate change scenarios will facilitate carbon cycling in coastal urban forest ecosystems.
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Hong, SungUk, Hyunsuk Jung, Chan Park, Hyunwoo Lee, HyongUk Kim, NamHyoung Lim, HyunUng Bae, KyungHo Kim, HongJip Kim, and Seong J. Cho. "Prediction of a representative point for rail temperature measurement by considering longitudinal deformation." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 233, no. 10 (March 6, 2019): 1003–11. http://dx.doi.org/10.1177/0954409718822866.
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Monitoring rail temperature is very important for determining the safe running speed of trains and to prevent buckling. In general, the maximum variation of the internal rail temperature can be >7 ℃ depending on the point of measurement. However, there is as yet no sufficient information about how to predict the measurement point to represent the thermal deformation due to temperature distribution. In this study, the authors report a new point, called the representative measurement point, at which the rail temperature can be measured. This point considers the average deformation of the rail through structural analysis by adopting experimental and actual rail temperature data. The authors designed and installed a measurement system similar to an actual rail environment. Using the system, various data were acquired (internal/surface rail temperature and weather data) for 10 months. On the basis of these data, an analysis was done to calculate the average deformation point through thermal analysis. Finally, the representative measurement point was proposed as the position at which the average deformation point converges regardless of weather or seasons. The authors believe that the method described herein is advantageous in that it could be used in a high-accuracy temperature-monitoring system and for predicting thermal deformation and buckling.
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White, BT, R. Nilsson, U. Olofsson, AD Arnall, MD Evans, T. Armitage, J. Fisk, DI Fletcher, and R. Lewis. "Effect of the presence of moisture at the wheel–rail interface during dew and damp conditions." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 232, no. 4 (May 2, 2017): 979–89. http://dx.doi.org/10.1177/0954409717706251.
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Incidents involving low levels of adhesion between the wheel and rail are a recurrent issue in the rail industry. The problem has been mitigated using friction modifiers and traction enhancers, but a significant number of incidents still occur throughout the year. This study looks at the environmental conditions that surround periods of low adhesion in order to provide an insight into why low adhesion events occur. Network Rail Autumn data, which provided details on the time and location of low adhesion incidents, were compared against weather data on a national and then local scale. Low adhesion incidents have often been attributed to contamination on the rails, such as organic leaf matter, but these incidents also occur when no contamination is visible. The time, date and location of incidents were linked to local weather data to establish any specific weather conditions that could lead to these events. The effects of precipitation, temperature and humidity on rails were analysed in order to further the understanding of low adhesion in the wheel–rail contact, which will lead to adopting better methods of mitigating this problem.
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Xiangyu, Duan, Zhu Liqiang, Yu Zujun, and Xu Xining. "The Verification of Rail Thermal Stress Measurement System." Periodica Polytechnica Transportation Engineering 48, no. 1 (April 16, 2019): 45–51. http://dx.doi.org/10.3311/pptr.12062.
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Continuous Welded Rail (CWR) is widely used in modern railways. With the absence of the expansion joints, CWR cannot expansion freely when the temperature changes, which could cause buckling in hot weather or breakage in cold weather. Therefore, rail thermal stress measuring system plays an important role in the safe operation of railways. This paper designed a thermal stress measurement system based on the acoustoelastic effect of the ultrasonic guided wave. A large-scale rail testbed was built to simulate the thermal stress in the rail track, and to establish the relationship of time-delay of guided wave and thermal stress. After laboratory testing, the system was installed in several railway lines in China for field tests. The results showed that the system was stable and accurate in stress measurement. The performance and potentials of the system were discussed.
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Chen, Zhenhua, Yuxuan Wang, and Lei Zhou. "Predicting weather-induced delays of high-speed rail and aviation in China." Transport Policy 101 (February 2021): 1–13. http://dx.doi.org/10.1016/j.tranpol.2020.11.008.
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Kampczyk, Arkadiusz, and Katarzyna Dybeł. "The Fundamental Approach of the Digital Twin Application in Railway Turnouts with Innovative Monitoring of Weather Conditions." Sensors 21, no. 17 (August 26, 2021): 5757. http://dx.doi.org/10.3390/s21175757.
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Improving railway safety depends heavily on the reliability of railway turnouts. The realization of effective, reliable and continuous observations for the spatial analysis and evaluation of the technical condition of railway turnouts is one of the factors affecting safety in railway traffic. The mode and scope of monitoring changes in geometric parameters of railway turnouts with associated indicators needs improvement. The application of digital twins to railway turnouts requires the inclusion of fundamental data indicating their condition along with innovative monitoring of weather conditions. This paper presents an innovative solution for monitoring the status of temperature and other atmospheric conditions. A UbiBot WS1 WIFI wireless temperature logger was used, with an external DS18B20 temperature sensor integrated into an S49 (49E1)-type rail as Tszyn WS1 WIFI. Measurements were made between January and May (winter/spring) at fixed time intervals and at the same measurement point. The aim of the research is to present elements of a fundamental approach of applying digital twins to railway turnouts requiring the consideration and demonstration of rail temperature conditions as a component in the data acquisition of railway turnout condition data and other constituent atmospheric conditions through an innovative solution. The research showed that the presented innovative solution is an effective support for the application of digital twins to railway turnouts and ongoing surveying and diagnostic work of other elements of rail transport infrastructure. The applicability of the TgCWRII second temperature difference indicator in the monitoring of railway turnouts was also confirmed.
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Romero, R., A. Martín, V. Homar, S. Alonso, and C. Ramis. "Predictability of prototype flash flood events in the Western Mediterranean under uncertainties of the precursor upper-level disturbance: the HYDROPTIMET case studies." Natural Hazards and Earth System Sciences 5, no. 4 (July 27, 2005): 505–25. http://dx.doi.org/10.5194/nhess-5-505-2005.
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Abstract. The HYDROPTIMET case studies (9–10 June 2000 Catalogne, 8–9 September 2002 Cévennes and 24–26 November 2002 Piémont) appear to encompass a sort of prototype flash-flood situations in the western Mediterranean attending to the relevant synoptic and mesoscale signatures identified on the meteorological charts. In Catalogne, the convective event was driven by a low-pressure system of relatively small dimensions developed over the mediterranean coast of Spain that moved into southern France. For Cévennes, the main circulation pattern was a synoptic-scale Atlantic low which induced a persistent southerly low-level jet (LLJ) over the western Mediterranean, strengthened by the Alps along its western flank, which guaranteed continuous moisture supply towards southern France where the long-lived, quasistationary convective system developed. The long Piémont episode, very representative of the most severe alpine flash flood events, shares some similarities with the Cévennes situation during its first stage in that it was controlled by a southerly moist LLJ associated with a large-scale disturbance located to the west. However, these circulation features were transient aspects and during the second half of the episode the situation was dominated by a cyclogenesis process over the Mediterranean which gave place to a mesoscale-size depression at surface that acted to force new heavy rain over the slopes of the Alps and maritime areas. That is, the Piémont episode can be catalogued as of mixed type with regard to the responsible surface disturbance, evolving from a large-scale pattern with remote action (like Cévennes) to a mesoscale pattern with local action (like Catalogne). A prominent mid-tropospheric trough or cut-off low can be identified in all events prior and during the period of heavy rain, which clearly served as the precursor agent for the onset of the flash-flood conditions and the cyclogenesis at low-levels. Being aware of the uncertainty in the representation of the upper-level disturbance and the necessity to cope with it within the operational context when attempting to issue short to mid-range numerical weather predictions of these high impact weather events, a systematic exploration of the predictability of the three selected case studies subject to uncertainties in the representation of the upper-level precursor disturbance is carried out in this paper. The study is based on an ensemble of mesoscale numerical simulations of each event with the MM5 non-hydrostatic model after perturbing in a systematic way the upper-level disturbance, in the sense of displacing slightly this disturbance upstream/downstream along the zonal direction and intensifying/weakening its amplitude. These perturbations are guided by a previous application of the MM5-adjoint model, which consistently shows high sensitivities of the dynamical control of the heavy rain to the flow configuration about the upper-level disturbance on the day before, thus confirming the precursor characteristics of this agent. The perturbations are introduced to the initial conditions by applying a potential vorticity (PV) inversion procedure to the positive PV anomaly associated with the upper-level disturbance, and then using the inverted fields (wind, temperature and geopotential) to modify under a physically consistent balance the model initial fields. The results generally show that the events dominated by mesoscale low-level disturbances (Catalogne and last stage of the Piémont episode) are very sensitive to the initial uncertainties, such that the heavy rain location and magnitude are in some of the experiments strongly changed in response to the "forecast errors" of the cyclone trajectory, intensity, shape and translational speed. In contrast, the other situations (Cévennes and initial stage of the Piémont episode), dominated by a larger scale system wich basically acts to guarantee the establishment and persistence of the southerly LLJ towards the southern France-north Italy orography, exhibit much higher predictability. That is, the slight modifications in the LLJ direction and intensity encompassed by the ensemble of perturbed forecasts are less critical with respect to the heavy precipitation potential and affected area.
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Szychta, Elzbieta, and Leszek Szychta. "Comparative Analysis of Effectiveness of Resistance and Induction Turnout Heating." Energies 13, no. 20 (October 10, 2020): 5262. http://dx.doi.org/10.3390/en13205262.
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Turnouts are key parts of rail roads and are exposed to adverse weather conditions such as snowfall, snow drifts, low temperatures, or sleet. Effective protection assures good turnout function and contributes to rail traffic efficiency and safety. Presently, resistance heating (RH) is the most common system of turnout heating in Europe. In this study, we attempted to implement energy-saving induction heating (IH) in order to cut costs of operation and electricity. A turnout heating test stand, including a stock-rail and a switch-rail, was executed in a climatic chamber. Air temperature was constant at the time of heating. Active power received by both the systems was identical for any measurement (450 W). Test results enabled an assessment of switch-rail position and variations of climatic chamber air temperature on growth of turnout temperatures. Effects of heating type on correct lubrication of the slide plate surface were compared. Dynamics of heating variations and their impact on effectiveness of snow or ice removal were defined for both heating systems. Turnout’s readiness for switch-rail shifting and lubrication conditions of turnout’s moving parts were compared. An in-depth comparative analysis of efficiency of RH and IH turnout heating was undertaken in the conclusion.
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Kennelly, Megan M., David M. Gadoury, Wayne F. Wilcox, Peter A. Magarey, and Robert C. Seem. "Primary Infection, Lesion Productivity, and Survival of Sporangia in the Grapevine Downy Mildew Pathogen Plasmopara viticola." Phytopathology® 97, no. 4 (April 2007): 512–22. http://dx.doi.org/10.1094/phyto-97-4-0512.
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Several aspects of grapevine downy mildew epidemiology that are fundamental to model predictions were investigated. Simple rainfall-, temperature-, and phenology-based thresholds (rain > 2.5 mm; temperature > 11°C; and phenology > Eichorn and Lorenz [E&L] growth stage 12) were evaluated to forecast primary (oosporic) infection by Plasmopara viticola. The threshold was consistent across 15 years of historical data on the highly susceptible cv. Chancellor at one site, and successfully predicted the initial outbreak of downy mildew for 2 of 3 years at three additional sites. Field inoculations demonstrated that shoot tissue was susceptible to infection as early as E&L stage 5, suggesting that initial germination of oospores, rather than acquisition of host susceptibility, was probably the limiting factor in the initiation of disease outbreaks. We also found that oospores may continue to germinate and cause infections throughout the growing season, in contrast to the widely-held assumption that the supply of oospores is depleted shortly after bloom. Lesion productivity (sporangia/lesion) did not decline with age of a lesion in the absence of suitable weather to induce sporulation. However, the productivity of all lesions declined rapidly through repeated cycles of sporulation. Extremely high temperatures (i.e., one day reaching 42.8°C) had an eradicative effect under vineyard conditions, and permanently reduced sporulation from existing (but not incubating) lesions to trace levels, despite a later return to weather conducive to sporulation. In fair weather, most sporangia died sometime during the daylight period immediately following their production. However, over 50% of sporangia still released zoospores after 12 to 24 h of exposure to overcast conditions.
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Srivastava, Jay Prakash, Prabir Kumar Sarkar, MV Ravi Kiran, and Vinayak Ranjan. "A numerical study on effects of friction-induced thermal load for rail under varied wheel slip conditions." SIMULATION 95, no. 4 (July 2, 2018): 351–62. http://dx.doi.org/10.1177/0037549718782629.
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A finite element-based simulation was carried out to investigate the effects of friction-induced thermal load on rail under varied wheel slip conditions. The surface temperature rise from six different percentage slips (1%, 1.5%, 2%, 5%, 8.5%, and 10%) at the contact interface was examined for eight-wheel pass. The residual stresses and accumulated plastic strains evolved by the effect of localized temperature rise are estimated. Analytical formulation for conduction mode of heat transfer at the contact patch is used to estimate the temperature distribution. The interaction of thermal-elastic-plastic field conditions is obtained by a proposed simulation model. This is implemented in commercial finite element software ANSYS 14.0. In order to capture the steep thermal gradient beneath the contact surface, refined mesh is used in the upper layers up to a depth of 2 mm of the simulation domain. For better manifestation of thermally affected material layers, a temperature dependent bilinear-kinematic hardening material condition is applied. Results indicate the maximum temperature rise at about 0.6 a from the trailing end in the contact ellipse of semi-major axis a. At higher slippage conditions the initial pearlitic rail steel gets converted to martensite which is often observed on rail surface as white etching layer known to be associated with rolling contact fatigue. The study reveals the mechanisms of thermally induced defects observable on rail surface. The outcomes, in addition, can provide useful information for the development of thermo-mechanically superior rail steels.
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Banerjee, Tathagata, and Sumedha Moharana. "Monitoring thermal defects in rail and rail joints using piezo impedance-based structural health monitoring (PISHM)." Engineering Research Express 4, no. 1 (February 10, 2022): 015014. http://dx.doi.org/10.1088/2631-8695/ac4e9a.
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Abstract Rail track derailment has been proven to be the cause of most of the rail accidents in recent years. High-temperature strains in railways caused by rail traction and thermal variation are the main causes of derailment, which lead to buckling. The likelihood of passenger deaths and maintenance costs will be reduced if thermal strains and failure in rails are detected early. This research attempts to provide a preventative strategy for detecting thermal strains and deformation caused by temperature fluctuations at railways. Using the electromechanical impedance (EMI) technique, piezoelectric sensors were used to acquire piezo coupled structural signatures for lab-sized rail samples, i.e. plain rail and rail joints, for gradual temperature escalation and repeat heat cycle. The experimental conductance signatures were obtained for the incremental rise in temperature (30–80 °C) in ambient conditions, and repetitive thermal cycles. To better diagnose structural problems induced only by the effect of heat on the host structure, thermal compensation is proposed. The piezo–coupled signatures for thermal changes in rail and rail junctions (weld and bolt) were found to be particularly effective in detecting incipient structural alterations for both steady and cyclic temperature variations. Statistical damage index was used to quantify the damage for all types of rail-joint bar caused due to temperature variation. Overall, this study has paved an experimental technique that can be used to detect early damage in rail and rail joints due to thermal loading.
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Zhu, Huaizhong, Xiaoguang Yang, and Yizhe Wang. "Prediction of Daily Entrance and Exit Passenger Flow of Rail Transit Stations by Deep Learning Method." Journal of Advanced Transportation 2018 (2018): 1–11. http://dx.doi.org/10.1155/2018/6142724.
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The prediction of entrance and exit passenger flow of rail transit stations is one of key research focuses in the area of intelligent transportation. Based on the big data of rail transit IC card (Public Transportation Card), this paper analyzes the data of major dynamic factors having effect on entrance passenger flow and exit passenger flow of rail transit stations: weather data, atmospheric temperature data, holiday and festival data, ground index data, and elevated road data and calculates the daily entrance passenger flow and daily exit passenger flow of individual rail transit stations with data reduction. Furthermore, based on the history data of passenger flow of rail transit stations and relevant influence factors, it applies the deep learning method to choose the relatively optimal hidden layer node by means of the cut-and-try method, set up input data and labeled data, select the activation function and loss function, and use the Adam Gradient Descent Optimization Algorithm for iterative global convergence. The results verify that this method accurately predicts the daily entrance passenger flow and daily exit passenger flow of rail transit stations with the prediction error of less than 4.1%. Finally, the proposed model is compared with the linear regression model.
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He, Hongbin, and Yongchun Ling. "A law for the temperature-induced stress distribution in continuously welded rail." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 229, no. 5 (January 6, 2014): 500–506. http://dx.doi.org/10.1177/0954409713516612.
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Li, Xiaowei, Qiangqiang Ma, Wenbo Wang, and Baojie Wang. "Influence of Weather Conditions on the Intercity Travel Mode Choice: A Case of Xi’an." Computational Intelligence and Neuroscience 2021 (August 23, 2021): 1–15. http://dx.doi.org/10.1155/2021/9969322.
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To explore the influence of weather conditions on the choice of the intercity travel mode of travelers, four modes of traveler transportation were studied in Xi'an, China, in March 2019: airplane, high-speed rail, conventional train, and express bus. The individual characteristics of travelers and intercity travel activity data were obtained, and they were matched with the weather characteristics at the departure time of the travelers. The Bayesian multinomial logit regression was employed to explore the relationship between the travel mode choice and weather characteristics. The results showed that temperature, relative humidity, rainfall, wind, air quality index, and visibility had significant effects on the travel mode selection of travelers, and the addition of these variables could improve the model’s predictive performance. The research results can provide a scientific decision basis for traveler flow transfer and the prediction of traffic modes choice due to the effects of climate change.
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Gu, Lijuan, Liang Zhang, Xiaoyi Bao, Merrina Zhang, Chengxian Zhang, and Yongkang Dong. "Detection of Thermal Strain in Steel Rails with BOTDA." Applied Sciences 8, no. 11 (October 23, 2018): 2013. http://dx.doi.org/10.3390/app8112013.
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Rail transportation is one of the most important and efficient forms of transportation. Large thermal strain can develop in the rail steel due to extreme climatic conditions resulting in safety related issues. We carried out a thermal-strain monitoring test on the rail specimen over a large temperature range from −40 ∘ C to +50 ∘ C using a Brillouin optical time-domain analyzer (BOTDA) for the first time, to the best of our knowledge. Two jacketed fibers and small-diameter carbon/polyimide-coating single-mode fiber were used for the purpose of investigating the jacket effect of thermal-strain detection on the rail. Although a nonlinear response to the temperature of the loose jacketed fiber was found, it was applicable for thermal strain monitoring when glued on the surface of the rail sample. The measured thermal strain in the rail specimen was validated by the results obtained by the strain gauge. The thermally induced strain from the large rail specimen was found to have suppressed the nonlinear impact of the fiber jacket.
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Price, Anna Elizabeth, Julian A. Reed, Savannah Long, Andrea L. Maslow, and Steven P. Hooker. "The Association of Natural Elements With Physical Activity Intensity During Trail Use by Older Adults." Journal of Physical Activity and Health 9, no. 5 (July 2012): 718–23. http://dx.doi.org/10.1123/jpah.9.5.718.
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Background:Public health efforts to promote trail use among older adults could be an effective strategy for increasing physical activity among older adults. However, research is needed to better understand factors that influence older adults’ use of trails.Purpose:To examine the association between variations in natural elements (ie, season, weather, temperature) and older adults’ overall trail use and physical activity intensity during trail use.Methods:A rail-trail in South Carolina was systematically evaluated (2006–2009) using The System for Observing Play and Recreation in Communities.Results:The majority (74.2%) of the 1053 older trail users observed were walking; 25.9% were observed in vigorous activity. Older adults were most often observed using the trail in the spring (40.1%), sunny weather (76.8%), and moderate temperatures (56.2%). Significant differences in activity type by natural element variables were identified.Conclusions:When promoting trail use among older adults, natural elements should be considered.
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Li, Li, and Yan Yun Luo. "Stable Analysis of CWR Track by its Vibration Characteristics." Advanced Materials Research 446-449 (January 2012): 2624–32. http://dx.doi.org/10.4028/www.scientific.net/amr.446-449.2624.
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Stress contained in rails, mainly due to thermally-induced expansion and contraction, results in large longitudinal loads which lead to broken rails and track buckling. According to the beam bending theory of structural dynamics with a consideration of the influence of axial load, a CWR track model is developed in the present study to be used for extensive buckling analysis of CWR tracks. The model discusses CWR track vibration characteristics with a length of unsupported rail subjected to the longitudinal force due to fluctuation of temperature. From the result, it can be gotten that the critical point of the temperature which may cause the rail have the danger of unstable. This model would help to evaluated and measure the real temperature in rail by analyzing the dynamic response of CWR track.
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Perry, Alexander G., Michael J. Korenberg, Geoffrey G. Hall, and Kieran M. Moore. "Modeling and Syndromic Surveillance for Estimating Weather-Induced Heat-Related Illness." Journal of Environmental and Public Health 2011 (2011): 1–10. http://dx.doi.org/10.1155/2011/750236.
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This paper compares syndromic surveillance and predictive weather-based models for estimating emergency department (ED) visits for Heat-Related Illness (HRI). A retrospective time-series analysis of weather station observations and ICD-coded HRI ED visits to ten hospitals in south eastern Ontario, Canada, was performed from April 2003 to December 2008 using hospital data from the National Ambulatory Care Reporting System (NACRS) database, ED patient chief complaint data collected by a syndromic surveillance system, and weather data from Environment Canada. Poisson regression and Fast Orthogonal Search (FOS), a nonlinear time series modeling technique, were used to construct models for the expected number of HRI ED visits using weather predictor variables (temperature, humidity, and wind speed). Estimates of HRI visits from regression models using both weather variables and visit counts captured by syndromic surveillance as predictors were slightly more highly correlated with NACRS HRI ED visits than either regression models using only weather predictors or syndromic surveillance counts.
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Glendinning, Stephanie, Paul Hughes, Peter Helm, Jonathan Chambers, Joao Mendes, David Gunn, Paul Wilkinson, and Sebastien Uhlemann. "Construction, management and maintenance of embankments used for road and rail infrastructure: implications of weather induced pore water pressures." Acta Geotechnica 9, no. 5 (May 13, 2014): 799–816. http://dx.doi.org/10.1007/s11440-014-0324-1.
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Potoski, Matthew, R. Urbatsch, and Cindy Yu. "Temperature Biases in Public Opinion Surveys*." Weather, Climate, and Society 7, no. 2 (April 1, 2015): 192–96. http://dx.doi.org/10.1175/wcas-d-15-0001.1.
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Abstract The quasi experiment of deviations from normal temperatures shows how local temperature conditions bias selected survey results. Responses in eight CBS News surveys from 2001 to 2007 change with the weather, with unseasonable temperatures reducing concern about climate change and unusually warm temperatures increasing presidential approval. Unusual temperatures also influence who answers surveys; wealthier respondents are overrepresented in warmer conditions. These results jointly suggest that surveys are at risk for temperature-induced response bias. Weighting-based methods can account for survey results’ temperature-induced differences in samples.
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Yan, Yihang, Dingjun Wu, and Qi Li. "A three-dimensional method for the simulation of temperature fields induced by solar radiation." Advances in Structural Engineering 22, no. 3 (August 28, 2018): 567–80. http://dx.doi.org/10.1177/1369433218795254.
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The determination of temperature fields is usually required for the calculation of structural deformation and stress induced by temperature variation. To guarantee the serviceability and safety of structures by improving calculation accuracy, this study presents a three-dimensional structural temperature field simulation framework that accounts for shadowing effects and changes in solar radiation intensity throughout the day. Field experiments were conducted to update the established model and to verify the accuracy of the numerical algorithm. The proposed method was finally applied in a case study to determine the temperature fields of both a rail and a U-shaped concrete girder. The results show that the temperature field of the concrete girder had obvious nonlinear distribution characteristics. Three-dimensional structural temperature field analysis is especially required for complicated structures with varied sections along the longitudinal axis.
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Djibo, Moumouni, Wendyam Boris Serge Ouedraogo, Ali Doumounia, Serge Sanou, Moumouni Sawadogo, Idrissa Guira, and François Zougmoré. "ESTIMATION DE LA VISIBILITÉ MÉTÉOROLOGIQUE À L’AIDE DES LIENS MICRO-ONDES COMMERCIAUX DE TÉLÉCOMMUNICATIONS." Journal de Physique de la SOAPHYS 3, no. 1 (November 15, 2021): C21A03–1—C21A03–4. http://dx.doi.org/10.46411/jpsoaphys.2021.01.03.
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Several factors can attenuate radio signal between transmitting and receiving antenna. One can cite: vegetation, atmospheric gases, fog, water vapor, transmission instruments, rain, temperature, etc... The sources of attenuation differ according to the climate and the relief of each continent or even each country. In this work we aim to show that there is link between microwave signal attenuation and weather visibility in the presence of dust. Weather visibility is a very important factor for the safety of road, sea, rail and air transportation. In the presence of dust, the visibility is strongly reduced and there is also a strong attenuation of the microwave signal propagating between two antennas. By performing a linear regression on the attenuation-visibility scatter plot, we propose a method for real-time estimation of the visibility knowing the microwave signals attenuation. A correlation measurement between the visibility estimated by our method from the real attenuation data of the mobile phone operator Telecel Faso SA (Burkina Faso) and the visibility measured by the National Meteorological Agency of Burkina Faso (ANAM) gave a correlation coefficient of 0.86.
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Leclerc, Martin, Arnaud Tarroux, Per Fauchald, Audun Stien, Torkild Tveraa, and Martin-Hugues St-Laurent. "Effects of human-induced disturbances and weather on herbivore movement." Journal of Mammalogy 100, no. 5 (June 27, 2019): 1490–500. http://dx.doi.org/10.1093/jmammal/gyz101.
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Abstract Human-caused habitat disturbances and climate change are leading threats to biodiversity. Studying the impacts of human activities on wildlife from a behavioral perspective is a relevant starting point to understand the mechanisms underlying population and species resistance and resilience to disturbances. In this study, we assessed the effects of weather (temperature and precipitation), habitat disturbances (roads and clearcuts), and natural habitat types on the space use patterns of a threatened boreal population of woodland caribou (Rangifer tarandus caribou). An extensive data set of 288,665 relocations from 50 adult females outfitted with GPS collars over 7 years in the boreal forest of Québec, Canada was used to evaluate residency time in natural and disturbed habitats for five distinct biologically defined periods. The most parsimonious linear mixed-effects model for each period showed that individuals stayed longer in more natural habitat types. During calving and summer, residency time decreased with increasing road density, whereas residency time decreased with increasing temperature during winter and spring. We found no evidence of a synergistic effect between daily weather and human disturbances on movement behavior of caribou, but consider their respective influence as additive. We also showed large individual variation in residency time, except during the calving period. Lower individual variation in residency time during calving may be explained by strong evolutionary constraints on behavior faced by females to ensure protection and survival of their offspring. Based on our results, we suggest keeping large patches of suitable and roadless habitat for caribou to favor the spacing-out antipredator strategy exhibited by females during calving. By tracking individuals over several complete annual cycles, we showed variation in the effects of daily weather and human disturbances on residency time across biological periods. Our study highlights that the inclusion of daily weather variables helps better understand space-use patterns of a threatened species.
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Cohen, François, and Antoine Dechezleprêtre. "Mortality, Temperature, and Public Health Provision: Evidence from Mexico." American Economic Journal: Economic Policy 14, no. 2 (May 1, 2022): 161–92. http://dx.doi.org/10.1257/pol.20180594.
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We examine the impact of temperature on mortality in Mexico using daily data over the period 1998–2017 and find that 3.8 percent of deaths in Mexico are caused by suboptimal temperature (26,000 every year). However, 92 percent of weather-related deaths are induced by cold (<12°C) or mildly cold ( 12–20°C) days and only 2 percent by outstandingly hot days (>32°C). Furthermore, temperatures are twice as likely to kill people in the bottom half of the income distribution. Finally, we show causal evidence that the Seguro Popular, a universal health care policy, has saved at least 1,600 lives per year from cold weather since 2004. (JEL I12, I13, I14, O13, O15, Q54)
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Yi, Gyu Sei, Hyun Ung Bae, Jin Yu Choi, and Nam Hyoung Lim. "Theoretical Approach to Offer a Rational Speed Reduction Scheme in Korea Railway." Applied Mechanics and Materials 204-208 (October 2012): 1918–22. http://dx.doi.org/10.4028/www.scientific.net/amm.204-208.1918.
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In order to ensure the safety of running train against the track buckling in a sultry weather, a speed reduction scheme has been implemented in railway operating companies. However, this scheme is based on the limited knowledge on the buckling behavior of the CWR track. The rational speed reduction scheme based on the probabilistic method for the buckling of the CWR track is proposed to apply to Korea high and normal speed railway. Permissible level of the reduced speed according to the rule of restricted speed signal, accepted degree of the buckling probability, the practically managing degree of the variation of the rail temperature, and effects of the maintenance work on the track condition are reflected in the rational speed reduction scheme.
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Hussein, Husam H., Issam Khoury, and Joshua S. Lucas. "Environment-Induced Performance of End Concrete Diaphragm in Skewed Semi-Integral Bridges." Buildings 12, no. 11 (November 16, 2022): 1985. http://dx.doi.org/10.3390/buildings12111985.
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Past research has shown that as skewed bridges change temperature, additional lateral movement or forces will occur along with the elongation of the bridge. Even though past research has documented this behavior, lateral movements of semi-integral bridge superstructure associated with temperature effects on bridge skewness have not been well predicted. In this study, the seasonal movements of a 24-year-old semi-integral bridge caused by temperature effects with skewed abutment have been investigated by conducting a series of field measurements on bridges subjected to various environmental climates. The measured data showed that as the bridge heated up, the superstructure tended to move toward the acute corner of the bridge, and the bridge would contract towards its obtuse corner with a negative temperature change. During warm weather, the cracks on the end diaphragm tended to open with a positive temperature change and close with a negative temperature change, which was much more predictable than the cold weather behavior. This behavior confirms that even though the bridge moves linearly with temperature, the end diaphragm response to the temperature depends on the season. Movement of the bridge superstructure from temperature change has caused cracks in the end diaphragm, which are now propagating to the deck. These cracks could damage the bridge enough that it would require repair work in the future. The evidence in this study will help provide a complete picture of seasonal jointless bridge behavior so future semi-integral bridges can be made safer and more efficient.
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Barnard, L., A. M. Portas, S. L. Gray, and R. G. Harrison. "The National Eclipse Weather Experiment: an assessment of citizen scientist weather observations." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 374, no. 2077 (September 28, 2016): 20150220. http://dx.doi.org/10.1098/rsta.2015.0220.
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The National Eclipse Weather Experiment (NEWEx) was a citizen science project designed to assess the effects of the 20 March 2015 partial solar eclipse on the weather over the United Kingdom (UK). NEWEx had two principal objectives: to provide a spatial network of meteorological observations across the UK to aid the investigation of eclipse-induced weather changes, and to develop a nationwide public engagement activity-based participation of citizen scientists. In total, NEWEx collected 15 606 observations of air temperature, cloudiness and wind speed and direction from 309 locations across the UK, over a 3 h window spanning the eclipse period. The headline results were processed in near real time, immediately published online, and featured in UK national press articles on the day of the eclipse. Here, we describe the technical development of NEWEx and how the observations provided by the citizen scientists were analysed. By comparing the results of the NEWEx analyses with results from other investigations of the same eclipse using different observational networks, including measurements from the University of Reading’s Atmospheric Observatory, we demonstrate that NEWEx provided a fair representation of the change in the UK meteorological conditions throughout the eclipse. Despite the simplicity of the approach adopted, robust reductions in both temperature and wind speed during the eclipse were observed. This article is part of the themed issue ‘Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse’.