Journal articles: 'Atmospheric sounding'

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Polyakov, S. V., V. O. Rapoport, and V. Yu Trakhtengerts. "Electroacoustic atmospheric sounding." Radiophysics and Quantum Electronics 35, no. 1 (January 1992): 9–15. http://dx.doi.org/10.1007/bf01064995.

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ANTHES, RICHARD A., YING-HWA KUO, CHRISTIAN ROCKEN, and WILLIAM S. SCHREINER. "Atmospheric sounding using GPS radio occultation." MAUSAM 54, no. 1 (January 18, 2022): 25–38. http://dx.doi.org/10.54302/mausam.v54i1.1489.

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This paper summarizes the radio occultation (RO) technique for remote sounding of the Earth’s atmosphere using the Global Positioning System (GPS) satellites and GPS receivers on low-Earth orbiting (LEO) satellites. As the LEO satellites rise and set with respect to the GPS satellites, the radio waves from the GPS satellites are refracted by the Earth’s atmosphere. Precise measurements of the bending angle of the radio waves are used to derive vertical profiles of atmospheric refractivity, which is a function of electron density in the ionosphere and temperature and water vapor in the stratosphere and troposphere. Results from the GPS/MET, CHAMP, and SAC-C RO missions are summarized, and examples of soundings are presented. Analysis of the CHAMP and SAC-C data indicates that approximately 45% of CHAMP and SAC-C retrieved radio occultation profiles reach below 1 km altitude, compared to only 35% for GPS/MET. All missions exhibit a negative refractivity bias in the lower troposphere of between 1% and 2% compared to NWP models. When constrained to the tropics, only about 20% of the CHAMP occultation profiles reach 1 km from the surface. Taiwan’s National Space Program Office (NSPO), the University Corporation for Atmospheric Research (UCAR), the Jet Propulsion Laboratory (JPL), the Naval Research Laboratory (NRL), and many partners in the university community are developing COSMIC (Constellation Observing System for Meteorology, Ionosphere and Climate), a follow-on project for weather and climate, space weather, and geodetic science. COSMIC plans to launch six satellites in 2005. Each satellite will retrieve 400-500 daily profiles† of key ionospheric and atmospheric properties from the tracked GPS radio signals as they are occulted behind the Earth limb. The radio occultation sounding data from COSMIC will contribute significantly to atmospheric research, weather forecasting, and climate modeling.

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Dunion, Jason P., and Christopher S. Marron. "A Reexamination of the Jordan Mean Tropical Sounding Based on Awareness of the Saharan Air Layer: Results from 2002." Journal of Climate 21, no. 20 (October 15, 2008): 5242–53. http://dx.doi.org/10.1175/2008jcli1868.1.

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Abstract The Jordan mean tropical sounding has provided a benchmark for representing the climatology of the tropical North Atlantic and Caribbean Sea since 1958. However, recent studies of the Saharan air layer (SAL) have suggested that the tropical atmosphere in these oceanic regions may contain two distinct soundings (SAL and non-SAL) with differing thermodynamic and kinematic structures and that a single mean sounding like Jordan’s does not effectively represent these differences. This work addresses this possibility by examining over 750 rawinsondes from the tropical North Atlantic Ocean and Caribbean Sea during the 2002 hurricane season. It was found that a two-peak bimodal moisture distribution (dry SAL and moist non-SAL) exists in this region and that the Jordan sounding does not represent either distribution particularly well. Additionally, SAL soundings exhibited higher values of geopotential height, unique temperature profiles, and stronger winds (with an enhanced easterly component) compared to the moist tropical non-SAL soundings. The results of this work suggest that the Jordan mean tropical sounding may need to be updated to provide a more robust depiction of the thermodynamics and kinematics that exist in the tropical North Atlantic Ocean and Caribbean Sea during the hurricane season.

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Dunion, Jason P. "Rewriting the Climatology of the Tropical North Atlantic and Caribbean Sea Atmosphere." Journal of Climate 24, no. 3 (February 1, 2011): 893–908. http://dx.doi.org/10.1175/2010jcli3496.1.

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Abstract The Jordan mean tropical sounding has provided a benchmark reference for representing the climatology of the tropical North Atlantic and Caribbean Sea atmosphere for over 50 years. However, recent observations and studies have suggested that during the months of the North Atlantic hurricane season, this region of the world is affected by multiple air masses with very distinct thermodynamic and kinematic characteristics. This study examined ∼6000 rawinsonde observations from the Caribbean Sea region taken during the core months (July–October) of the 1995–2002 hurricane seasons. It was found that single mean soundings created from this new dataset were very similar to C. L. Jordan’s 1958 sounding work. However, recently developed multispectral satellite imagery that can track low- to midlevel dry air masses indicated that the 1995–2002 hurricane season dataset (and likely Jordan’s dataset as well) was dominated by three distinct air masses: moist tropical (MT), Saharan air layer (SAL), and midlatitude dry air intrusions (MLDAIs). Findings suggest that each sounding is associated with unique thermodynamic, kinematic, stability, and mean sea level pressure characteristics and that none of these soundings is particularly well represented by a single mean sounding such as Jordan’s. This work presents three new mean tropical soundings (MT, SAL, and MLDAI) for the tropical North Atlantic Ocean and Caribbean Sea region and includes information on their temporal variability, thermodynamics, winds, wind shear, stability, total precipitable water, and mean sea level pressure attributes. It is concluded that the new MT, SAL, and MLDAI soundings presented here provide a more robust depiction of the tropical North Atlantic and Caribbean Sea atmosphere during the Atlantic hurricane season and should replace the Jordan mean tropical sounding as the new benchmark soundings for this part of the world.

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Menzel, W. Paul, Timothy J. Schmit, Peng Zhang, and Jun Li. "Satellite-Based Atmospheric Infrared Sounder Development and Applications." Bulletin of the American Meteorological Society 99, no. 3 (March 1, 2018): 583–603. http://dx.doi.org/10.1175/bams-d-16-0293.1.

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Abstract Atmospheric sounding of the vertical changes in temperature and moisture is one of the key contributions from meteorological satellites. The concept of using satellite infrared radiation observations for retrieving atmospheric temperature was first proposed by Jean I. F. King. Lewis D. Kaplan noted that the radiation from different spectral regions are primarily emanating from different atmospheric layers, which can be used to retrieve the atmospheric temperature at different heights in the atmosphere. The United States launched the first meteorological satellite Television Infrared Observation Satellite-1 (TIROS-1) on 1 April 1960, opening a new era of observing the Earth and its atmosphere from space. Since then, hundreds of meteorological satellites have been launched by space agencies, including those in Europe, China, Japan, Russia, India, Korea, and others. With the rapid development of atmospheric sounding technology and radiative transfer models, it became possible to determine the atmospheric state from combined satellite- and ground-based measurements. With advances in computing power, forecast model development, data assimilation, and observing technologies, numerical weather prediction (NWP) has achieved consistently better results and thereby improved the prediction and early warning of severe weather events as well as fostered the initial monitoring of global climate change. The purpose of this paper is to summarize and discuss the development of satellite vertical sounding capability, quantitative profile retrieval theory, and applications of satellite-based atmospheric sounding measurements, with a focus on infrared sounding.

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Blackwell, William J., Laura J. Bickmeier, R. Vincent Leslie, Michael L. Pieper, Jenna E. Samra, Chinnawat Surussavadee, and Carolyn A. Upham. "Hyperspectral Microwave Atmospheric Sounding." IEEE Transactions on Geoscience and Remote Sensing 49, no. 1 (January 2011): 128–42. http://dx.doi.org/10.1109/tgrs.2010.2052260.

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Siméoni, D., C. Singer, and G. Chalon. "Infrared atmospheric sounding interferometer." Acta Astronautica 40, no. 2-8 (January 1997): 113–18. http://dx.doi.org/10.1016/s0094-5765(97)00098-2.

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Romanovskii, Oleg A., Sergey A. Sadovnikov, Olga V. Kharchenko, and Semen V. Yakovlev. "Opo lidar sounding of trace atmospheric gases in the 3 – 4 μm spectral range." EPJ Web of Conferences 176 (2018): 05016. http://dx.doi.org/10.1051/epjconf/201817605016.

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The applicability of a KTA crystal-based laser system with optical parametric oscillators (OPO) generation to lidar sounding of the atmosphere in the spectral range 3–4 μm is studied in this work. A technique developed for lidar sounding of trace atmospheric gases (TAG) is based on differential absorption lidar (DIAL) method and differential optical absorption spectroscopy (DOAS). The DIAL-DOAS technique is tested to estimate its efficiency for lidar sounding of atmospheric trace gases. The numerical simulation performed shows that a KTA-based OPO laser is a promising source of radiation for remote DIAL-DOAS sounding of the TAGs under study along surface tropospheric paths. A possibility of using a PD38-03-PR photodiode for the DIAL gas analysis of the atmosphere is shown.

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Li, Shuqun, Hao Hu, Chenggege Fang, Sichen Wang, Shangpei Xun, Binfang He, Wenyu Wu, and Yanfeng Huo. "Hyperspectral Infrared Atmospheric Sounder (HIRAS) Atmospheric Sounding System." Remote Sensing 14, no. 16 (August 10, 2022): 3882. http://dx.doi.org/10.3390/rs14163882.

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Accurate atmospheric temperature and moisture profiles are essential for weather forecasts and research. Satellite-based hyperspectral infrared observations are meaningful in detecting atmospheric profiles, especially over oceans where conventional observations can seldom be used. In this study, a HIRAS (Hyperspectral Infrared Atmospheric Sounder) Atmospheric Sounding System (HASS) was introduced, which retrieves atmospheric temperature and moisture profiles using a one-dimension variational scheme based on HIRAS observations. A total of 274 channels were optimally selected from the entire HIRAS spectrum through information entropy analyses, and a group of retrieval experiments were independently performed for different HIRAS fields of views (FOVs). Compared with the ECMWF reanalysis data version-5 (ERA5), the RMSEs of temperature (relative humidity) for low-, mid-, and high-troposphere layers were 1.5 K (22.3%), 1.0 K (33.2%), and 1.3 K (38.5%), respectively, which were similar in magnitude to those derived from other hyperspectral infrared sounders. Meanwhile, the retrieved temperature RMSEs with respect to the satellite radio occultation (RO) products increased to 1.7 K, 1.8 K, and 1.9 K for the low-, mid-, and high-troposphere layers, respectively, which could be attributed to the accurate RO temperature products in the upper atmospheres. It was also found that the RMSE varied with the FOVs and latitude, which may be caused by the current angle-dependent bias correction and unique background profiles.

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Potvin, Corey K., Kimberly L. Elmore, and Steven J. Weiss. "Assessing the Impacts of Proximity Sounding Criteria on the Climatology of Significant Tornado Environments." Weather and Forecasting 25, no. 3 (June 1, 2010): 921–30. http://dx.doi.org/10.1175/2010waf2222368.1.

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Abstract Proximity sounding studies typically seek to optimize several trade-offs that involve somewhat arbitrary definitions of how to define a “proximity sounding.” More restrictive proximity criteria, which presumably produce results that are more characteristic of the near-storm environment, typically result in smaller sample sizes that can reduce the statistical significance of the results. Conversely, the use of broad proximity criteria will typically increase the sample size and the apparent robustness of the statistical analysis, but the sounding data may not necessarily be representative of near-storm environments, given the presence of mesoscale variability in the atmosphere. Previous investigations have used a wide range of spatial and temporal proximity criteria to analyze severe storm environments. However, the sensitivity of storm environment climatologies to the proximity definition has not yet been rigorously examined. In this study, a very large set (∼1200) of proximity soundings associated with significant tornado reports is used to generate distributions of several parameters typically used to characterize severe weather environments. Statistical tests are used to assess the sensitivity of the parameter distributions to the proximity criteria. The results indicate that while soundings collected too far in space and time from significant tornadoes tend to be more representative of the larger-scale environment than of the storm environment, soundings collected too close to the tornado also tend to be less representative due to the convective feedback process. The storm environment itself is thus optimally sampled at an intermediate spatiotemporal range referred to here as the Goldilocks zone. Implications of these results for future proximity sounding studies are discussed.

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Bryan, George H., and Matthew D. Parker. "Observations of a Squall Line and Its Near Environment Using High-Frequency Rawinsonde Launches during VORTEX2." Monthly Weather Review 138, no. 11 (November 1, 2010): 4076–97. http://dx.doi.org/10.1175/2010mwr3359.1.

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Abstract Rawinsonde data were collected before and during passage of a squall line in Oklahoma on 15 May 2009 during the Second Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX2). Nine soundings were released within 3 h, allowing for unprecedented analysis of the squall line’s internal structure and nearby environment. Four soundings were released in the prestorm environment and they document the following features: low-level cooling associated with the reduction of solar isolation by a cirrus anvil; abrupt warming (1.5 K in 30 min) above the boundary layer, which is probably attributable to a gravity wave; increases in both low-level and deep-layer vertical wind shear within 100 km of the squall line; and evidence of ascent extending at least 75 km ahead of the squall line. The next sounding was released ∼5 km ahead of the squall line’s gust front; it documented a moist absolutely unstable layer within a 2-km-deep layer of ascent, with vertical air velocity of approximately 6 m s−1. Another sounding was released after the gust front passed but before precipitation began; this sounding showed the cold pool to be ∼4 km deep, with a cold pool intensity C ≈ 35 m s−1, even though this sounding was located only 8 km behind the surface gust front. The final three soundings were released in the trailing stratiform region of the squall line, and they showed typical features such as: “onion”-shaped soundings, nearly uniform equivalent potential temperature over a deep layer, and an elevated rear inflow jet. The cold pool was 4.7 km deep in the trailing stratiform region, and extended ∼1 km above the melting level, suggesting that sublimation was a contributor to cold pool development. A mesoscale analysis of the sounding data shows an upshear tilt to the squall line, which is consistent with the cold pool intensity C being much larger than a measure of environmental vertical wind shear ΔU. This dataset should be useful for evaluating cloud-scale numerical model simulations and analytic theory, but the authors argue that additional observations of this type should be collected in future field projects.

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Li, Yuanlong, Yuqing Wang, Yanluan Lin, and Rong Fei. "Dependence of Superintensity of Tropical Cyclones on SST in Axisymmetric Numerical Simulations." Monthly Weather Review 148, no. 12 (December 2020): 4767–81. http://dx.doi.org/10.1175/mwr-d-20-0141.1.

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AbstractThis study revisits the superintensity of tropical cyclones (TCs), which is defined as the excess maximum surface wind speed normalized by the corresponding theoretical maximum potential intensity (MPI), based on ensemble axisymmetric numerical simulations, with the focus on the dependence of superintensity on the prescribed sea surface temperature (SST) and the initial environmental atmospheric sounding. Results show a robust decrease of superintensity with increasing SST regardless of being in experiments with an SST-independent initial atmospheric sounding or in those with the SST-dependent initial atmospheric soundings as in nature sorted for the western North Pacific and the North Atlantic. It is found that the increase in either convective activity (and thus diabatic heating) in the TC outer region or theoretical MPI or both with increasing SST could reduce the superintensity. For a given SST-independent initial atmospheric sounding, the strength of convective activity in the TC outer region increases rapidly with increasing SST due to the rapidly increasing air–sea thermodynamic disequilibrium (and thus potential convective instability) with increasing SST. As a result, the decrease of superintensity with increasing SST in the SST-independent sounding experiments is dominated by the increasing convective activity in the TC outer region and is much larger than that in the SST-dependent sounding experiments, and the TC intensity becomes sub-MPI at relatively high SSTs in the former. Due to the marginal increasing tendency of convective activity in the TC outer region, the decrease of superintensity in the latter is dominated by the increase in theoretical MPI with increasing SST.

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Skopeliti, Andriani, Leda Stamou, Lysandros Tsoulos, and Shachak Pe’eri. "Generalization of Soundings across Scales: From DTM to Harbour and Approach Nautical Charts." ISPRS International Journal of Geo-Information 9, no. 11 (November 20, 2020): 693. http://dx.doi.org/10.3390/ijgi9110693.

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This paper presents an integrated digital methodology for the generalization of soundings. The input for the sounding generalization procedure is a high resolution Digital Terrain Model (DTM) and the output is a sounding data set appropriate for portrayal on harbour and approach Electronic Navigational Charts (ENCs). The sounding generalization procedure follows the “ladder approach” that is a requisite for the portrayal of soundings on nautical charts, i.e., any sounding portrayed on a smaller scale chart should also be depicted on larger scale charts. A rhomboidal fishnet is used as a supportive reference structure based on the cartographic guidance for soundings to display a rhombus pattern on nautical charts. The rhomboidal fishnet cell size is defined by the depth range and the compilation scale of the charted area. Generalization is based on a number of rules and constraints extracted from International Hydrographic Organization (IHO) standards, hydrographic offices’ best practices and the cartographic literature. The sounding generalization procedure can be implemented using basic geoprocessing functions available in the most commonly used Geographic Information System (GIS) environments. A case study was performed in the New York Lower Bay area based on a high resolution National Oceanic and Atmospheric Administration (NOAA) DTM. The method successfully produced generalized soundings for a number of Harbour and Approach nautical charts at 10 K, 20 K, 40 K and 80 K scales.

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Vladimirov, V. M., V. N. Ratushnyak, V. A. Vyakhirev, and I. V. Tyapkin. "Features of scanning the atmosphere and building radar stations of vertical sounding with a low-element antenna array." Spacecrafts & Technologies 3, no. 4 (December 25, 2019): 237–42. http://dx.doi.org/10.26732/2618-7957-2019-4-237-242.

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The mobility and variability of the atmosphere and near-Earth space make it extremely important to obtain experimental information about its dynamic characteristics – speed, wind direction and degree of turbulence. One of the promising methods for obtaining these data is vertical radar sounding of the atmosphere. Vertical sounding radars or wind profilometers are a relatively new type of equipment for studying the atmosphere and thermosphere. Vertical sounding radars are designed for remote non-contact determination of wind speed parameters above the sounding point in the troposphere and the lower part of the thermosphere. To obtain information on the dynamics of atmospheric movements the phenomenon of reflection of electromagnetic waves from turbulent formations and formations of a different nature is used. The temporal position of the reflected signal and the frequency shift due to the Doppler effect give accurate information about the height and speed of movement of atmospheric inhomogeneities. An analysis of the parameters of the reflected signals makes it possible to obtain in real time the altitude-time field of the wind speed and turbulence intensity. The physical principles underlying the operation of these stations allow continuous measurements, regardless of weather conditions. The article discusses the main methods for measuring the vertical profile of the atmosphere and the lower part of the thermosphere, scanning methods and classification of sounding means for the vertical profile of the atmosphere, as well as the features of the functioning and construction of vertical sounding radars with a low-element array.

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Johnson, Richard H., Steven F. Williams, and Paul E. Ciesielski. "Legacy Atmospheric Sounding Dataset Project." Bulletin of the American Meteorological Society 93, no. 1 (January 2012): 14–17. http://dx.doi.org/10.1175/bams-d-11-00092.1.

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Kalina, Evan A., Katja Friedrich, Hugh Morrison, and George H. Bryan. "Aerosol Effects on Idealized Supercell Thunderstorms in Different Environments." Journal of the Atmospheric Sciences 71, no. 12 (November 26, 2014): 4558–80. http://dx.doi.org/10.1175/jas-d-14-0037.1.

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Abstract Idealized supercell thunderstorms are simulated with the Weather Research and Forecasting (WRF) Model at 15 cloud condensation nuclei (CCN) concentrations (100–10 000 cm−3) using four environmental soundings with different low-level relative humidity (RH) and vertical wind shear values. The Morrison microphysics scheme is used with explicit prediction of cloud droplet number concentration and a variable shape parameter for the raindrop size distribution (results from simulations with a fixed shape parameter are also presented). Changes in the microphysical process rates with CCN concentration are negligible beyond CCN ≈ 3000 cm−3. Changes in cold pool characteristics with CCN concentration are nonmonotonic and highly dependent on the environmental conditions. In moist conditions with moderate vertical wind shear, the cold pool area is nearly constant with respect to CCN concentration, while the area is reduced by 84% and 22% in the soundings with dry RH and large vertical wind shear, respectively. With the exception of the dry RH sounding, domain-averaged precipitation peaks between 500 and 5000 cm−3, after which it remains constant or slowly decreases. For the dry RH sounding, the domain-averaged precipitation monotonically decreases with CCN concentration. Accumulated precipitation is enhanced (by up to 25 mm) in the most polluted cases near the updrafts, except for the dry RH sounding. The different responses for moist and dry soundings are mostly due to increased (decreased) low-level latent cooling from melting hail (evaporating rain) with increasing CCN concentration in the moist soundings. This compensating effect does not exist when the low-level RH is dry.

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Fan, Z. Q., Z. Sheng, H. Q. Shi, X. H. Zhang, and C. J. Zhou. "A Characterization of the Quality of the Stratospheric Temperature Distributions from SABER based on Comparisons with COSMIC Data." Journal of Atmospheric and Oceanic Technology 33, no. 11 (November 2016): 2401–13. http://dx.doi.org/10.1175/jtech-d-16-0085.1.

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AbstractGlobal stratospheric temperature measurement is an important field in the study of climate and weather. Dynamic and radiative coupling between the stratosphere and troposphere has been demonstrated in a number of studies over the past decade or so. However, studies of the stratosphere were hampered by a shortage of observation data before satellite technology was used in atmospheric sounding. Now, the data from the Thermosphere, Ionosphere, Mesosphere Energetics, and Dynamics/Sounding of the Atmosphere using Broadband Emission Radiometry (TIMED/SABER) observations make it easier to study the stratosphere. The precision and accuracy of TIMED/SABER satellite soundings in the stratosphere are analyzed in this paper using refraction error data and temperature data obtained from the Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) radio occultation sounding system and TIMED/SABER temperature data between April 2006 and December 2009. The results show high detection accuracy of TIMED/SABER satellite soundings in the stratosphere. The temperature standard deviation (STDV) errors of SABER are mostly in the range from of 0–3.5 K. At 40 km the STDV error is usually less than 1 K, which means that TIMED/SABER temperature is close to the real atmospheric temperature at this height. The distributions of SABER STDV errors follow a seasonal variation: they are approximately similar in the months that belong to the same season. As the weather situation is complicated and fickle, the distribution of SABER STDV errors is most complex at the equator. The results in this paper are consistent with previous research and can provide further support for application of the SABER’s temperature data.

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Mears, Carl A., and Frank J. Wentz. "Construction of the Remote Sensing Systems V3.2 Atmospheric Temperature Records from the MSU and AMSU Microwave Sounders." Journal of Atmospheric and Oceanic Technology 26, no. 6 (June 1, 2009): 1040–56. http://dx.doi.org/10.1175/2008jtecha1176.1.

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Abstract Measurements made by microwave sounding instruments provide a multidecadal record of atmospheric temperature change. Measurements began in late 1978 with the launch of the first Microwave Sounding Unit (MSU) and continue to the present. In 1998, the first of the follow-on series of instruments—the Advanced Microwave Sounding Units (AMSUs)—was launched. To continue the atmospheric temperature record past 2004, when measurements from the last MSU instrument degraded in quality, AMSU and MSU measurements must be intercalibrated and combined to extend the atmospheric temperature data records. Calibration methods are described for three MSU–AMSU channels that measure the temperature of thick layers of the atmosphere centered in the middle troposphere, near the tropopause, and in the lower stratosphere. Some features of the resulting datasets are briefly summarized.

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Ciesielski, Paul E., and Richard H. Johnson. "Small Island Effects in DYNAMO and Their Impact on Large-Scale Budget Analyses." Journal of Applied Meteorology and Climatology 60, no. 4 (April 2021): 577–94. http://dx.doi.org/10.1175/jamc-d-20-0238.1.

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AbstractDuring the Dynamics of the MJO (DYNAMO) field campaign, radiosonde launches were regularly conducted from three small islands/atolls (Malé and Gan, Maldives, and Diego Garcia, British Indian Ocean Territory) as part of a large-scale sounding network. Comparison of island upsondes with nearby and near-contemporaneous dropsondes over the ocean provides evidence for the magnitude and scope of the islands’ influence on the surrounding atmosphere and on the island upsonde profiles. The island’s impact on the upsonde data is most prominent in the lowest 200 m. Noting that the vertical gradients of temperature, moisture, and winds over the ocean are generally constant in the lowest 0.5 km of dropsondes, a simple procedure was constructed to adjust the upsonde profiles in the lowest few hundred meters to resemble the atmospheric structures over the open ocean. This procedure was applied to the soundings from the three islands mentioned above for the October–December 2011 period of DYNAMO. As a result of this procedure, the adjusted diurnal cycle amplitude of surface temperature is reduced fivefold, resembling that over the ocean, and low-level wind speeds are increased in ~90% of the island soundings. Examination of the impact of these sounding adjustments shows that dynamical and budget fields are primarily affected by adjustments to the wind field, whereas convective parameters are sensitive to the adjustments in thermodynamic fields. Although the impact of the adjustments is generally small (on the order of a few percent), intraseasonal wind regime changes result in some systematic variations in divergence and vertical motion over the sounding arrays.

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Zhou, Daniel K., William L. Smith, Xu Liu, Allen M. Larar, Stephen A. Mango, and Hung-Lung Huang. "Physically Retrieving Cloud and Thermodynamic Parameters from Ultraspectral IR Measurements." Journal of the Atmospheric Sciences 64, no. 3 (March 1, 2007): 969–82. http://dx.doi.org/10.1175/jas3877.1.

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Abstract A physical inversion scheme has been developed dealing with cloudy as well as cloud-free radiance observed with ultraspectral infrared sounders to simultaneously retrieve surface, atmospheric thermodynamic, and cloud microphysical parameters. A fast radiative transfer model, which applies to the clouded atmosphere, is used for atmospheric profile and cloud parameter retrieval. A one-dimensional (1D) variational multivariable inversion solution is used to improve an iterative background state defined by an eigenvector-regression retrieval. The solution is iterated in order to account for nonlinearity in the 1D variational solution. It is shown that relatively accurate temperature and moisture retrievals can be achieved below optically thin clouds. For optically thick clouds, accurate temperature and moisture profiles down to cloud-top level are obtained. For both optically thin and thick cloud situations, the cloud-top height can be retrieved with relatively high accuracy (i.e., error <1 km). National Polar-orbiting Operational Environmental Satellite System (NPOESS) Airborne Sounder Testbed Interferometer (NAST-I) retrievals from the The Observing-System Research and Predictability Experiment (THORPEX) Atlantic Regional Campaign are compared with coincident observations obtained from dropsondes and the nadir-pointing cloud physics lidar (CPL). This work was motivated by the need to obtain solutions for atmospheric soundings from infrared radiances observed for every individual field of view, regardless of cloud cover, from future ultraspectral geostationary satellite sounding instruments, such as the Geosynchronous Imaging Fourier Transform Spectrometer (GIFTS). However, this retrieval approach can also be applied to the ultraspectral sounding instruments to fly on polar satellites, such as the Infrared Atmospheric Sounding Interferometer (IASI) on the European MetOp satellite, the Cross-track Infrared Sounder (CrIS) on the NPOESS Preparatory Project, and the follow-on NPOESS series of satellites.

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Liu, Hui, and Jun Li. "An Improvement in Forecasting Rapid Intensification of Typhoon Sinlaku (2008) Using Clear-Sky Full Spatial Resolution Advanced IR Soundings." Journal of Applied Meteorology and Climatology 49, no. 4 (April 1, 2010): 821–27. http://dx.doi.org/10.1175/2009jamc2374.1.

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Abstract Hyperspectral infrared (IR) sounders, such as the Atmospheric Infrared Sounder (AIRS) and the Infrared Atmospheric Sounding Interferometer (IASI), provide unprecedented global atmospheric temperature and moisture soundings with high vertical resolution and accuracy. In this paper, the authors investigate whether advanced IR soundings of water vapor and temperature observations can improve the analysis of a tropical cyclone vortex and the forecast of rapid intensification of a tropical cyclone. Both the IR water vapor and temperature soundings significantly improve the typhoon vortex in the analysis and the forecast of the rapid intensification of Typhoon Sinlaku (2008). The typhoon track forecast is also substantially improved when the full spatial resolution AIRS soundings are assimilated. This study demonstrates the potential important application of high spatial and hyperspectral IR soundings in forecasting tropical cyclones.

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Yao, Zhigang, Jun Li, Jinlong Li, and Hong Zhang. "Surface Emissivity Impact on Temperature and Moisture Soundings from Hyperspectral Infrared Radiance Measurements." Journal of Applied Meteorology and Climatology 50, no. 6 (June 2011): 1225–35. http://dx.doi.org/10.1175/2010jamc2587.1.

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AbstractAn accurate land surface emissivity (LSE) is critical for the retrieval of atmospheric temperature and moisture profiles along with land surface temperature from hyperspectral infrared (IR) sounder radiances; it is also critical to assimilating IR radiances in numerical weather prediction models over land. To investigate the impact of different LSE datasets on Atmospheric Infrared Sounder (AIRS) sounding retrievals, experiments are conducted by using a one-dimensional variational (1DVAR) retrieval algorithm. Sounding retrievals using constant LSE, the LSE dataset from the Infrared Atmospheric Sounding Interferometer (IASI), and the baseline fit dataset from the Moderate Resolution Imaging Spectroradiometer (MODIS) are performed. AIRS observations over northern Africa on 1–7 January and 1–7 July 2007 are used in the experiments. From the limited regional comparisons presented here, it is revealed that the LSE from the IASI obtained the best agreement between the retrieval results and the ECMWF reanalysis, whereas the constant LSE gets the worst results when the emissivities are fixed in the retrieval process. The results also confirm that the simultaneous retrieval of atmospheric profile and surface parameters could reduce the dependence of soundings on the LSE choice and finally improve sounding accuracy when the emissivities are adjusted in the iterative retrieval. In addition, emissivity angle dependence is investigated with AIRS radiance measurements. The retrieved emissivity spectra from AIRS over the ocean reveal weak angle dependence, which is consistent with that from an ocean emissivity model. This result demonstrates the reliability of the 1DVAR simultaneous algorithm for emissivity retrieval from hyperspectral IR radiance measurements.

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Wang, Ling, Marvin A. Geller, and David C. Fritts. "Direct Numerical Simulation Guidance for Thorpe Analysis to Obtain Quantitatively Reliable Turbulence Parameters." Journal of Atmospheric and Oceanic Technology 36, no. 11 (November 2019): 2247–55. http://dx.doi.org/10.1175/jtech-d-18-0225.1.

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AbstractThorpe analysis has been used to study turbulence in the atmosphere and ocean. It is clear that Thorpe analysis applied to individual soundings cannot be expected to give quantitatively reliable measurements of turbulence parameters because of the instantaneous nature of the measurement. A critical aspect of this analysis is the assumption of the linear relationship C = LO/LT between the Thorpe scale LT, derived from the sounding measurements, and the Ozmidov scale LO. It is the determination of LO that enables determination of the dissipation rate of turbulence kinetic energy ε. Single atmospheric and oceanic soundings cannot indicate either the source of turbulence or the stage of its evolution; different values of C are expected for different turbulence sources and stages of the turbulence evolution and thus cannot be expected to yield quantitatively reliable turbulence parameters from individual profiles. The variation of C with the stage of turbulence evolution is illustrated for direct numerical simulation (DNS) results for gravity wave breaking. Results from a DNS model of multiscale initiation and evolution of turbulence with a Reynolds number Re (which is defined using the vertical wavelength of the primary gravity wave and background buoyancy period as length and time scales, respectively) of 100 000 are sampled as in sounding of the atmosphere and ocean, and various averaging of the sounding results indicates a convergence to a well-defined value of C, indicating that applying Thorpe analysis to atmospheric or oceanic soundings and averaging over a number of profiles gives more reliable turbulence determinations. The same averaging study is also carried out when the DNS-modeled turbulence is dominated by turbulence growing from the initial instabilities, when the turbulence is fully developed, when the modeled turbulence is decaying, and when the turbulence is in a still-later decaying stage. These individual cases converge to well defined values of C, but these values of C show a large variation resulting from the different stages of turbulence evolution. This study gives guidance as to the accuracy of Thorpe analysis of turbulence as a function of the number of profiles being averaged. It also suggests that the values of C in different environments likely depend on the dominant turbulence initiation mechanisms and on the Reynolds number of the environment.

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Sussmann, R., and T. Borsdorff. "Interference errors in infrared remote sounding of the atmosphere." Atmospheric Chemistry and Physics Discussions 6, no. 6 (December 12, 2006): 13027–73. http://dx.doi.org/10.5194/acpd-6-13027-2006.

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Abstract. More and more profiles of atmospheric state parameters are being retrieved from remote soundings in the infrared spectral domain. Classical error analysis, which was originally applied to microwave sounding systems, distinguishes between "smoothing errors," "forward model errors," "forward model parameter errors," and "retrieval noise errors". We show that for infrared soundings "interference errors", which have not been treated up to now, can be significant. Interference errors originate from "interfering species" that introduce signatures into the spectral measurement which overlap with the spectral features used for retrieval of the target species. This is a frequent situation in infrared atmospheric spectra where the vibration-rotation bands of different species often overlap; it is not the case in the microwave region. This paper presents a full theoretical formulation of interference errors. It requires a generalized state vector including profile entries for all interfering species. This leads to a generalized averaging kernel matrix made up of classical averaging kernels plus here defined "interference kernels". The latter are used together with climatological covariances for the profiles of the interfering species in order to quantify the interference errors. To illustrate the methods we apply them to a real sounding and show that interference errors have a significant impact on standard CO profile retrievals from ground-based mid-infrared solar absorption spectra. We also demonstrate how to minimize overall error, which is a trade-off between minimizing interference errors and the smoothing error. The approach used in this paper can be applied to soundings of all infrared-active atmospheric species, which includes more than two dozen different gases relevant to climate and ozone. And this holds for all kind of infrared remote sounding systems, i.e., retrievals from ground-based, balloon-borne, airborne, or satellite spectroradiometers.

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Houston, Adam L., and Jason M. Keeler. "Sounding Characteristics that Yield Significant Convective Inhibition Errors due to Ascent Rate and Sensor Response of In Situ Profiling Systems." Journal of Atmospheric and Oceanic Technology 37, no. 7 (July 1, 2020): 1163–72. http://dx.doi.org/10.1175/jtech-d-19-0191.1.

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AbstractAccurate measurements of the convective inhibition (CIN) associated with capping inversions are critical to forecasts of deep convection initiation. The goal of this work is to determine the sounding characteristics most vulnerable to CIN errors arising from hysteresis associated with sensor response and ascent rate of profiling systems. This examination uses 5058 steady-state analytic soundings prescribed using three free parameters that control inversion depth, static stability, and moisture content. A theoretical well-aspirated first-order sensor mounted on a platform that does not disturb its environment is “flown” in these soundings. Sounding characteristics that result in the largest relative CIN errors are also the characteristics that result in the smallest CIN. Because they are more likely to support deep convection initiation, it is particularly critical that environments with small CIN are represented accurately. The relationship between relative CIN error and CIN exists because sounding characteristics that contribute to large CIN do not proportionally increase the CIN error. Analysis also considers CIN intervals with (operationally important) CIN on the threshold between environments that will and will not support deep convection initiation. For these soundings, CIN error is found to be largest for deep, dry inversions characterized by small static stability.

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26

Bianco, Laura, Katja Friedrich, James M. Wilczak, Duane Hazen, Daniel Wolfe, Ruben Delgado, Steven P. Oncley, and Julie K. Lundquist. "Assessing the accuracy of microwave radiometers and radio acoustic sounding systems for wind energy applications." Atmospheric Measurement Techniques 10, no. 5 (May 9, 2017): 1707–21. http://dx.doi.org/10.5194/amt-10-1707-2017.

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Abstract. To assess current remote-sensing capabilities for wind energy applications, a remote-sensing system evaluation study, called XPIA (eXperimental Planetary boundary layer Instrument Assessment), was held in the spring of 2015 at NOAA's Boulder Atmospheric Observatory (BAO) facility. Several remote-sensing platforms were evaluated to determine their suitability for the verification and validation processes used to test the accuracy of numerical weather prediction models.The evaluation of these platforms was performed with respect to well-defined reference systems: the BAO's 300 m tower equipped at six levels (50, 100, 150, 200, 250, and 300 m) with 12 sonic anemometers and six temperature (T) and relative humidity (RH) sensors; and approximately 60 radiosonde launches.In this study we first employ these reference measurements to validate temperature profiles retrieved by two co-located microwave radiometers (MWRs) as well as virtual temperature (Tv) measured by co-located wind profiling radars equipped with radio acoustic sounding systems (RASSs). Results indicate a mean absolute error (MAE) in the temperature retrieved by the microwave radiometers below 1.5 K in the lowest 5 km of the atmosphere and a mean absolute error in the virtual temperature measured by the radio acoustic sounding systems below 0.8 K in the layer of the atmosphere covered by these measurements (up to approximately 1.6–2 km). We also investigated the benefit of the vertical velocity correction applied to the speed of sound before computing the virtual temperature by the radio acoustic sounding systems. We find that using this correction frequently increases the RASS error, and that it should not be routinely applied to all data.Water vapor density (WVD) profiles measured by the MWRs were also compared with similar measurements from the soundings, showing the capability of MWRs to follow the vertical profile measured by the sounding and finding a mean absolute error below 0.5 g m−3 in the lowest 5 km of the atmosphere. However, the relative humidity profiles measured by the microwave radiometer lack the high-resolution details available from radiosonde profiles. An encouraging and significant finding of this study was that the coefficient of determination between the lapse rate measured by the microwave radiometer and the tower measurements over the tower levels between 50 and 300 m ranged from 0.76 to 0.91, proving that these remote-sensing instruments can provide accurate information on atmospheric stability conditions in the lower boundary layer.

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27

Zaprudnyi, A. A., V. G. Pletnev, and A. L. Verkhorobin. "High Luminance Lasers for Atmospheric Sounding." Telecommunications and Radio Engineering 51, no. 6-7 (1997): 140–43. http://dx.doi.org/10.1615/telecomradeng.v51.i6-7.220.

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Lalande, J. M., O. Sèbe, M. Landès, Ph Blanc-Benon, R. S. Matoza, A. Le Pichon, and E. Blanc. "Infrasound data inversion for atmospheric sounding." Geophysical Journal International 190, no. 1 (May 22, 2012): 687–701. http://dx.doi.org/10.1111/j.1365-246x.2012.05518.x.

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29

ASIMAKOPOULOS, D. N., and C. G. HELMIS. "Recent advances on atmospheric acoustic sounding." International Journal of Remote Sensing 15, no. 2 (January 1994): 223–33. http://dx.doi.org/10.1080/01431169408954066.

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30

RILEY, J. R. "Acoustic sounding, atmospheric structure and insects." International Journal of Remote Sensing 15, no. 2 (January 1994): 293–97. http://dx.doi.org/10.1080/01431169408954072.

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31

Noël, S., J. P. Burrows, H. Bovensmann, J. Frerick, K. V. Chance, A. H. P. Goede, and C. Muller. "Atmospheric trace gas sounding with SCIAMACHY." Advances in Space Research 26, no. 12 (January 2000): 1949–54. http://dx.doi.org/10.1016/s0273-1177(00)00166-6.

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32

Mcgowan, Hamish A., and Andrew P. Sturman. "A kite based atmospheric sounding system." Boundary-Layer Meteorology 77, no. 3-4 (February 1996): 395–99. http://dx.doi.org/10.1007/bf00123534.

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33

Smith Sr., W. L., H. Revercomb, G. Bingham, A. Larar, H. Huang, D. Zhou, J. Li, X. Liu, and S. Kireev. "Technical Note: Evolution, current capabilities, and future advance in satellite nadir viewing ultra-spectral IR sounding of the lower atmosphere." Atmospheric Chemistry and Physics 9, no. 15 (August 6, 2009): 5563–74. http://dx.doi.org/10.5194/acp-9-5563-2009.

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Abstract. Infrared ultra-spectral spectrometers have brought in a new era in satellite remote atmospheric sounding capability. During the 1970s, after the implementation of the first satellite sounding instruments, it became evident that much higher vertical resolution sounding information was needed to be able to forecast life and property threatening localized severe weather. The demonstration of the ultra-spectral radiance measurement technology required to achieve higher vertical resolution began in 1985, with the aircraft flights of the High resolution Interferometer Sounder (HIS) instrument. The development of satellite instruments designed to have a HIS-like measurement capability was initiated in the late 1980's. Today, after more than a decade of development time, the Atmospheric Infrared Sounder (AIRS) and the Infrared Atmospheric Sounding Interferometer (IASI) are now operating successfully from the Aqua and MetOp polar orbiting satellites. The successful development and ground demonstration of the Geostationary Imaging Fourier Transform Spectrometer (GIFTS), during this decade, is now paving the way toward the implementation of the ultra-spectral sounding capability on the international system of geostationary environmental satellites. This note reviews the evolution of the satellite ultra-spectral sounding systems, shows examples of current polar satellite sounding capability, and discusses future advances planned for geostationary orbit.

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34

Jewell, Ryan, and Julian Brimelow. "Evaluation of Alberta Hail Growth Model Using Severe Hail Proximity Soundings from the United States." Weather and Forecasting 24, no. 6 (December 1, 2009): 1592–609. http://dx.doi.org/10.1175/2009waf2222230.1.

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Abstract A one-dimensional, coupled hail and cloud model (HAILCAST) is tested to assess its ability to predict hail size. The model employs an ensemble approach when forecasting maximum hail size, uses a sounding as input, and can be run in seconds on an operational workstation. The model was originally developed in South Africa and then improved upon in Canada, using high quality hail verification data for calibration. In this study, the model was run on a spatially and seasonally diverse set of 914 modified severe hail proximity soundings collected within the contiguous United States between 1989 and 2004. Model output was then compared to the maximum observed hail size for each proximity sounding. Basic verification statistics are presented, showing that the HAILCAST model exhibits considerable skill that can be of use to the operational severe weather forecaster.

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35

Liao, M., P. Zhang, G. L. Yang, Y. M. Bi, Y. Liu, W. H. Bai, X. G. Meng, Q. F. Du, and Y. Q. Sun. "Preliminary validation of refractivity from a new radio occultation sounder GNOS/FY-3C." Atmospheric Measurement Techniques Discussions 8, no. 9 (September 1, 2015): 9009–44. http://dx.doi.org/10.5194/amtd-8-9009-2015.

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Abstract. As a new member of space-based radio occultation sounder, the GNOS (Global Navigation Satellite System Occultation Sounder) mounted on FY-3C has been carrying out the atmospheric sounding since 23 September 2013. GNOS takes a daily measurement up to 800 times with GPS (Global Position System) and Chinese BDS (BeiDou navigation satellite) signals. The refractivity profiles from GNOS are compared with the co-located ECMWF (European Centre for Medium-Range Weather Forecasts) analyses in this paper. Bias and standard deviation have being calculated as the function of altitude. The mean bias is about 0.2 % from the near surface to 35 km. The average standard deviation is within 2 % while it is down to about 1 % in the range 5–30 km where best soundings are usually made. To evaluate the performance of GNOS, COSMIC (Constellation Observing System for Meteorology, Ionosphere and Climate) and GRAS/METOP-A (GNSS Receiver for Atmospheric Sounding) data are also compared to ECMWF analyses as the reference. The results show that GNOS/FY-3C meets the requirements of the design well. It possesses a sounding capability similar to COSMIC and GRAS in the vertical range of 0–30 km, though it needs improvement in higher altitude. Generally, it provides a new data source for global NWP (numerical weather prediction) community.

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36

Gallice, A., F. G. Wienhold, C. R. Hoyle, F. Immler, and T. Peter. "Modeling the ascent of sounding balloons: derivation of the vertical air motion." Atmospheric Measurement Techniques 4, no. 10 (October 20, 2011): 2235–53. http://dx.doi.org/10.5194/amt-4-2235-2011.

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Abstract. A new model to describe the ascent of sounding balloons in the troposphere and lower stratosphere (up to ∼30–35 km altitude) is presented. Contrary to previous models, detailed account is taken of both the variation of the drag coefficient with altitude and the heat imbalance between the balloon and the atmosphere. To compensate for the lack of data on the drag coefficient of sounding balloons, a reference curve for the relationship between drag coefficient and Reynolds number is derived from a dataset of flights launched during the Lindenberg Upper Air Methods Intercomparisons (LUAMI) campaign. The transfer of heat from the surrounding air into the balloon is accounted for by solving the radial heat diffusion equation inside the balloon. In its present state, the model does not account for solar radiation, i.e. it is only able to describe the ascent of balloons during the night. It could however be adapted to also represent daytime soundings, with solar radiation modeled as a diffusive process. The potential applications of the model include the forecast of the trajectory of sounding balloons, which can be used to increase the accuracy of the match technique, and the derivation of the air vertical velocity. The latter is obtained by subtracting the ascent rate of the balloon in still air calculated by the model from the actual ascent rate. This technique is shown to provide an approximation for the vertical air motion with an uncertainty error of 0.5 m s−1 in the troposphere and 0.2 m s−1 in the stratosphere. An example of extraction of the air vertical velocity is provided in this paper. We show that the air vertical velocities derived from the balloon soundings in this paper are in general agreement with small-scale atmospheric velocity fluctuations related to gravity waves, mechanical turbulence, or other small-scale air motions measured during the SUCCESS campaign (Subsonic Aircraft: Contrail and Cloud Effects Special Study) in the orographically unperturbed mid-latitude middle troposphere.

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37

Solyanik, O. A., and A. G. Karabanov. "Low-Potential Atmospheric Vertical-Sounding Radar Station." Telecommunications and Radio Engineering 51, no. 8 (1997): 13–15. http://dx.doi.org/10.1615/telecomradeng.v51.i8.30.

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38

Kartashov, V. M. "Signal Scattering Functions of Atmospheric Sounding Systems." Telecommunications and Radio Engineering 59, no. 7-9 (2003): 7. http://dx.doi.org/10.1615/telecomradeng.v59.i7-9.70.

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39

Rapoport, V. O., N. S. Bellyustin, V. A. Zinichev, N. A. Mityakov, N. A. Ryzhov, and Yu A. Sazonov. "Experimental Remote Sounding of the Atmospheric Turbulence." Radiophysics and Quantum Electronics 47, no. 1 (January 2004): 30–33. http://dx.doi.org/10.1023/b:raqe.0000031668.97720.a5.

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40

Chesters, Dennis, Anthony Mostek, and Dennis A. Keyser. "VAS Sounding Images of Atmospheric Stability Parameters." Weather and Forecasting 1, no. 1 (June 1986): 5–22. http://dx.doi.org/10.1175/1520-0434(1986)001<0005:vsioas>2.0.co;2.

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41

Bellmore, Michael A., D. Ray Booker, and Ken Winter. "An Air-Launched Atmospheric Sounding System (ALMET)." Journal of Atmospheric and Oceanic Technology 11, no. 1 (February 1994): 154–60. http://dx.doi.org/10.1175/1520-0426(1994)011<0154:aalass>2.0.co;2.

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42

Asmus, V. V., Yu M. Timofeyev, A. V. Polyakov, A. B. Uspensky, Yu M. Golovin, F. S. Zavelevich, D. A. Kozlov, et al. "Atmospheric temperature sounding with the Fourier spectrometer." Izvestiya, Atmospheric and Oceanic Physics 53, no. 4 (July 2017): 428–32. http://dx.doi.org/10.1134/s0001433817040028.

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43

Shamanaeva, Lyudmila G. "Opto‐acoustic sounding of the atmospheric parameters." Journal of the Acoustical Society of America 105, no. 2 (February 1999): 1378. http://dx.doi.org/10.1121/1.426518.

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44

Schanda, E., K. Künzi, N. Kämpfer, G. Hartmann, W. Degenhart, E. Keppler, A. Loidl, et al. "Millimeter wave atmospheric sounding from space shuttle." Acta Astronautica 13, no. 9 (September 1986): 553–63. http://dx.doi.org/10.1016/0094-5765(86)90057-3.

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45

Té, Yao, Pascal Jeseck, Claude Camy-Peyret, Sébastien Payan, Gaetan Perron, and Ginette Aubertin. "Balloonborne calibrated spectroradiometer for atmospheric nadir sounding." Applied Optics 41, no. 30 (October 20, 2002): 6431. http://dx.doi.org/10.1364/ao.41.006431.

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46

Garcia, Xavier, and Alan G. Jones. "Atmospheric sources for audio-magnetotelluric (AMT) sounding." GEOPHYSICS 67, no. 2 (March 2002): 448–58. http://dx.doi.org/10.1190/1.1468604.

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The energy sources for natural-source magnetotelluric (MT) frequencies > 1 Hz are electromagnetic (EM) waves caused by distant lightning storms and which propagate within the Earth–ionosphere waveguide. The properties of this waveguide display diurnal, seasonal, and 11-year solar-cycle fluctuations, and these temporal fluctuations cause significant signal amplitude attenuation variations—especially at frequencies in the 1- to 5-kHz so-called audiomagnetotelluric (AMT) dead band. In the northern hemisphere these variations increase in amplitude during the nighttime and the summer months, and they correspondingly decrease during the daytime and the winter months. Thus, one problem associated with applying the AMT method for shallow (<3 km) exploration can be the lack of signal in certain frequency bands during the desired acquisition interval. In this paper we analyze the time variations of high-frequency EM fields to assess the limitations of the efficient applicability of the AMT method. We demonstrate that magnetic field sensors need to become two orders of magnitude more sensitive than they are currently to acquire an adequate signal at all times. We present a proposal for improving AMT acquisition involving continuous profiling of the telluric field only during the daytime and AMT acquisition at a few base stations through the night.

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47

Sterlyadkin, V. V., and T. M. Khapaev. "An inverse problem of atmospheric radar sounding." Computational Mathematics and Modeling 7, no. 2 (1996): 258–62. http://dx.doi.org/10.1007/bf01131354.

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48

King, Austin T., and Aaron D. Kennedy. "North American Supercell Environments in Atmospheric Reanalyses and RUC-2." Journal of Applied Meteorology and Climatology 58, no. 1 (January 2019): 71–92. http://dx.doi.org/10.1175/jamc-d-18-0015.1.

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AbstractA suite of modern atmospheric reanalyses is analyzed to determine how they represent North American supercell environments. This analysis is performed by comparing a database of Rapid Update Cycle (RUC-2) proximity soundings with profiles derived from the nearest grid point in each reanalysis. Parameters are calculated using the Sounding and Hodograph Analysis and Research Program in Python (SHARPpy), an open-source Python sounding-analysis package. Representation of supercell environments varies across the reanalyses, and the results have ramifications for climatological studies that use these datasets. In particular, thermodynamic parameters such as the convective available potential energy (CAPE) show the widest range in biases, with reanalyses falling into two camps. The North American Regional Reanalysis (NARR) and the Japanese 55-year Reanalysis (JRA-55) are similar to RUC-2, but other reanalyses have a substantial negative bias. The reasons for these biases vary and range from thermodynamic biases at the surface to evidence of convective contamination. Overall, it is found that thermodynamic biases feed back to other convective parameters that incorporate CAPE directly or indirectly via the effective layer. As a result, significant negative biases are found for indices such as the supercell composite parameter. These biases are smallest for NARR and JRA-55. Kinematic parameters are more consistent across the reanalyses. Given the issues with thermodynamic properties, better segregation of soundings by storm type is found for fixed-layer parameters than for effective-layer shear parameters. Although no reanalysis can exactly reproduce the results of earlier RUC-2 studies, many of the reanalyses can broadly distinguish between environments that are significantly tornadic versus nontornadic.

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Smith, W. L., H. Revercomb, G. Bingham, A. Larar, H. Huang, D. Zhou, J. Li, X. Liu, and S. Kireev. "Evolution, current capabilities, and future advances in satellite ultra-spectral IR sounding." Atmospheric Chemistry and Physics Discussions 9, no. 2 (March 10, 2009): 6541–69. http://dx.doi.org/10.5194/acpd-9-6541-2009.

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Abstract. Infrared ultra-spectral spectrometers have brought in a new era of satellite remote atmospheric sounding capability. During the 1970's, after the implementation of the first satellite sounding instruments, it became evident that much higher vertical resolution sounding information was needed to be able to forecast life and property threatening localized severe weather. The demonstration of the ultra-spectral radiance measurement technology required to achieve higher vertical resolution began in 1985, with the aircraft flights of the High-resolution Interferometer Sounder (HIS) instrument. The development of satellite instruments designed to have a HIS-like measurement capability was initiated in the late 1980's. Today, after more than a decade of development time, the Atmospheric Infrared Sounder (AIRS) and the Infrared Atmospheric Sounding Interferometer (IASI) are now operating successfully from the Aqua and MetOp polar orbiting satellites, respectively. The successful development and ground demonstration of the Geostationary Imaging Fourier Transform Spectrometer (GIFTS), during this decade, is now paving the way toward future implementation of the ultra-spectral sounding capability on the international system of geostationary environmental satellites.

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Belov, M. L., A. A. Samsonova, S. E. Ivanov, and V. A. Gorodnichev. "Impact Analysis of the Atmosphere Optical State on Wind Lidar Sounding Range." Radio Engineering, no. 4 (September 27, 2020): 30–43. http://dx.doi.org/10.36027/rdeng.0420.0000174.

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One of the most important questions for correlation lidars is the sounding range question.Correlation lidar sounding range greatly depends not only on the parameters of the equipment, but also on the optical state of the earth's atmosphere.In addition, there are currently two approaches to the estimation of lidar sounding range. In one approach, an estimate of the sounding range is obtained by equating the detector threshold power to the laser signal power recorded by the detector. In another approach, an estimate of the sounding range is obtained by equating the minimum detectable energy of the detected laser signal energy.This paper is about impact research of the atmosphere optical state on wind correlation lidar sounding range and compare sounding range estimates obtained under the two different approaches to the energy calculation lidar.The analysis is carried out for the surface layer of the atmosphere, the horizontal sounding path and the radiation wavelength of 0.532 μm. In atmospheric haze conditions, an empirical formula is used for the attenuation factor. The signal-to-noise ratio is assumed to be 100.Solid-state Nd:YAG Ekspla lasers NL319 (lamp pumping, pulse energy 5 J) and NL231-100 (diode pumping, pulse energy 90 mJ) were chosen as radiation sources.Hamamatsu photomultiplier tube R5070A with radiant sensitivity ~ 50 mA/W was chosen as a detector.It is shown that in a wide optical state range (meteorological range of visibility from 20 to 2 km) the lamp-pumped laser source sounding range with pulse energy 5 J varies from ~ 3,8 km to ~ 1,2 km and the diode-pumped laser source sounding range with pulse energy 90 mJ varies from ~ 1,1 km to ~ 0,64 km.The approach based on comparison of the detector threshold power with the received laser signal power overestimates the sounding range due to incomplete influencing consideration factors.

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Journal articles on the topic 'Atmospheric sounding'

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