Literatura científica selecionada sobre o tema "Multi-Layers energy budget"

Abstract. This paper presents radiative transfer calculations performed over Niamey in the UV-Visible range over the period 26th January – 1st February during the African Multidisciplinary Monsoon Analysis (AMMA) international program. Climatic effects of aerosols along the vertical column have required an accurate determination of their optical properties, which are presented in for a variety of instrumented platforms: Ultralight aircraft, Facility for Airborne Atmospheric Measurements (FAAM) research aircraft, AERONET station. Measurements highlighted the presence of a multi-layered structure of mineral dust located below and biomass-burning particles in the more elevated layers. Radiative forcing was affected by both the scattering and absorption effects governed by the aerosol complex refractive index (ACRI). The best agreement between our results and AERONET optical thicknesses, ground-based extinction measurements and NO2 photolysis rate coefficient was found using the synergy between all the instrumented platforms. The corresponding averaged ACRI were 1.53 (±0.04)–0.047i (±0.006) and 1.52 (±0.04)–0.008i (±0.001) for biomass-burning and mineral dust aerosols, respectively. Biomass-burning aerosols were characterized by single-scattering albedo ranging from 0.78 to 0.82 and asymmetry parameter ranging from 0.71 to 0.73. For dust aerosols, single-scattering albedo (asymmetry parameter) ranged from 0.9 to 0.92 (0.73 to 0.75). The solar energy depletion at the surface is shown to be ~ −21.2 (±1.7) W/m2 as a daily average. At the TOA, the radiative forcing appeared slightly negative but very close to zero (~ −1.4 W/m2). The corresponding atmospheric radiative forcing was found to be ~19.8 (±2.3) W/m2. Mineral dust located below a more absorbing layer act as an increase in surface reflectivity of ~3–4%. The radiative forcing is also shown to be highly sensitivity the optical features of the different aerosol layers (ACRI, optical thickness and aerosol vertical distribution).

Abstract. This paper presents radiative transfer calculations performed over Niamey in the UV-Visible range over the period 26th January–1st February 2006 during the African Multidisciplinary Monsoon Analysis (AMMA) international program. Climatic effects of aerosols along the vertical column have required an accurate determination of their optical properties, which are presented here for a variety of instrumented platforms: Ultralight aircraft, Facility for Airborne Atmospheric Measurements (FAAM) research aircraft, AERONET station. Measurements highlighted the presence of a multi-layered structure of mineral dust located below and biomass-burning particles in the more elevated layers. Radiative forcing was affected by both the scattering and absorption effects governed by the aerosol complex refractive index (ACRI). The best agreement between our results and AERONET optical thicknesses, ground-based extinction measurements and NO2 photolysis rate coefficient was found using the synergy between all the instrumented platforms. The corresponding averaged ACRI at 355 nm were 1.53 (±0.04) −0.047i (±0.006) and 1.52 (±0.04) −0.008i (±0.001) for biomass-burning and mineral dust aerosols, respectively. Biomass-burning aerosols were characterized by single-scattering albedo ranging from 0.78 to 0.82 and asymmetry parameter ranging from 0.71 to 0.73. For dust aerosols, single-scattering albedo (asymmetry parameter) ranged from 0.9 to 0.92 (0.73 to 0.75). The solar energy depletion at the surface is shown to be ~−21.2 (±1.7) W/m2 as a daily average. At the TOA, the radiative forcing appeared slightly negative but very close to zero (~−1.4 W/m2). The corresponding atmospheric radiative forcing was found to be ~19.8 (±2.3) W/m2. Mineral dust located below a more absorbing layer act as an increase in surface reflectivity of ~3–4%. The radiative forcing is also shown to be highly sensitive to the optical features of the different aerosol layers (ACRI, optical thickness and aerosol vertical distribution).

Wind is one of the most promising sources of alternative energy. The construction of wind farms grows quickly in China. It is necessary for stakeholders to estimate investment costs and make good decisions on a wind power project by making a budget for the investment. However, the identification of rational investment practices is technically challenging because of the lack of scientific tools to evaluate optimal decisions. A multi-criteria evaluation method was proposed to select rational investment strategy for wind farm construction. The method is based on the analytic hierarchy process (AHP) together with a technique for order preference by similarity to ideal solution (TOPSIS). A decision problem hierarchy with three layers were investigated. The top layer is an objective layer for evaluating the investment rationality. The intermediate layer includes three evaluation criteria, that is, configuration of wind turbine generator systems, physical environment and social environment. Some relative and important indicators for each criterion are in the low layer. The evaluation results illustrate that the proposed method is practical and helpful to indentify the investment rationality for wind farms.

Abstract Aerosols play a significant role in regional scale pollution that alters the cloud formation process, radiation budget, and climate. Here, using long-term (2003–2019) observations from multi-satellite and ground-based remote sensors, we show robust aerosol-induced instantaneous daytime lower tropospheric cooling during the pre-monsoon season over the Indian core monsoon region (ICMR). Quantitatively, an average cooling of −0.82 °C ± 0.11 °C to −1.84 °C ± 0.25 °C is observed in the lower troposphere. The observed cooling is associated with both aerosol-radiation and aerosol-cloud-radiation interaction processes. The elevated dust and polluted-dust layers cause extinction of the incoming solar radiation, thereby decreasing the lower tropospheric temperature. The aerosol-cloud interactions also contribute to enhancement of cloud fraction which further contributes to the lower tropospheric cooling. The observed cooling results in a stable lower tropospheric structure during polluted conditions, which can also feedback to cloud systems. Our findings suggest that aerosol induced lower tropospheric cooling can strongly affect the cloud distribution and circulation dynamics over the ICMR, a region of immense hydroclimatic importance.

The role of the industrial sector in total greenhouse gas (GHG) emissions and resource consumption is well-known, and many industrial activities may have a negative environmental impact. The solution to decreasing the negative effects cannot be effective without the consideration of sustainable development. There are several methods for sustainability evaluation, such as tools based on products, processes, or plants besides supply chain or life cycle analysis, and there are different rating systems suggesting 80, 140, or more indicators for assessment. The critical point is the limits such as required techniques and budget in using all indicators for all factories in the beginning. Moreover, the weight of each indicator might change based on the selected alternative that it is not a fixed value and could change in a new case study. In this regard, to determine the impact and weight of different indicators in sustainable factories, a multi-layer Triangular Fuzzy Analytic Hierarchy Process (TFAHP) approach was developed, and the application of the method was described and verified. The defined layers are six; for each layer, the pairwise comparison matrix was developed, and the total aggregated score concerning the sustainability goal for each alternative was calculated that shows the Relative Importance Coefficient (RIC). The method is formulated in a way that allows adding the new indicators in all layers as the verification shows, and thus, there are no limits for using any green rating systems. Therefore, the presented approach by TFAHP would provide an additional tool toward the sustainable development of factories.

Terrestrial water storage (TWS) is of great importance to the global water and energy budget, which modulates the hydrological cycle and then determines the spatiotemporal distributions of water resources availability. The Tibetan Plateau is the birthplace of the Yangtze, Yellow, and Lancang–Mekong River, where the water resources are directly related to the life of the Eastern and Southeastern Asian people. Based on multi-source datasets during the period 1981–2015, the long-term spatiotemporal variabilities of the TWS over the Tibetan Plateau were investigated by the Sen’s slope and Mann–Kendall test trend analysis methods; the changing mechanisms were explored from two perspectives of components analysis and the hydrological cycle. The water conservation capacity of vegetation in the alpine mountainous areas was also discussed by geostatistical methods such as correlation analysis, extracted by attributes and zonal statistics. The results show that the TWS of the Tibetan Plateau increased with the speed of 0.7 mm/yr as the precipitation accumulated and the glaciers melted during the period 1981–2015. The TWS values were low and generally present a trend of obvious accumulation over the northern Tibetan Plateau, while the high and decreasing values were distributed in the south of Tibetan Plateau. The results of the components analysis indicate that the TWS mainly consisted of soil moisture at one-fourth layers, which are 0–200 cm underground in most areas of the Tibetan Plateau. The precipitation is mainly lost through evapotranspiration over the northern Tibetan Plateau, while in the northwestern corner of the Tibetan Plateau, the Himalayas, and northeastern Yarlung Zangbo River basin, the runoff coefficients were larger than 1.0 due to the influence of snow melting. In the alpine mountains, different climate and vegetation conditions have complex effects on water resources. The results are helpful for understanding the changing mechanism of water storage over the Tibetan Plateau and have scientific meaning for the development, utilization, and protection of regional water resources.

Abstract. A one-dimensional multi-layer scheme describing the coupled exchange of energy and CO2, the emission of isoprene and the dry deposition of ozone is applied to a rain forest canopy in southwest Amazonia. The model was constrained using mean diel cycles of micrometeorological quantities observed during two periods in the wet and dry season 1999. Predicted net fluxes and concentration profiles for both seasonal periods are compared to observations made at two nearby towers. The predicted day- and nighttime thermal stratification of the canopy layer is consistent with observations in dense canopies. The observed and calculated net fluxes above and H2O and CO2 concentration profiles within the canopy show a good agreement. The predicted net carbon sink decreases from 2.5 t C ha-1yr-1 for wet season conditions to 1 t C ha-1yr-1 for dry season conditions, whereas observed and predicted midday Bowen ratio increases from 0.5 to 0.8. The evaluation results confirmed a seasonal variability of leaf physiological parameters, as already suggested in the companion study. The predicted midday canopy net flux of isoprene increased from 7.1 mg C m-2h-1 during the wet season to 11.4 mg C m-2h-1 during the late dry season. Applying a constant emission capacity in all canopy layers, resulted in a disagreement between observed and simulated profiles of isoprene concentrations, suggesting a smaller emission capacity of shade adapted leaves and deposition to the soil or leaf surfaces. Assuming a strong light acclimation of emission capacity, equivalent to a 66% reduction of the standard emission factor for leaves in the lower canopy, resulted in a better agreement of observed and calculated concentration profiles and a 30% reduction of the canopy net flux. The mean calculated ozone flux for dry season condition at noontime was ≈12 nmol m-2s-1, agreeing well with observed values. The corresponding deposition velocity increased from 0.8 cm s-1 to >1.6 cm s-1 in the wet season, which can not be explained by increased stomatal uptake. Considering reasonable physiological changes in stomatal regulation, the predicted value was not larger than 1.05 cm s-1. Instead, the observed fluxes could be explained with the model by decreasing the cuticular resistance to ozone deposition from 5000 to 1000 s m-1. For doubled atmospheric CO2 concentrations the model predicts a strong increase of surface temperatures (0.1–1°C) and net assimilation (22%), a considerable shift in the energy budget (≈25% decreasing transpiration and increasing sensible heat), a slight increase of isoprene emissions (10%) and a strong decrease of ozone deposition (35%).

The quantity of municipal solid waste (MSW) generation is escalating at an alarming rate with every passing year alongside the modernization of our economy. Unfortunately, the majority of this waste remains uncollected or ends up in open dumping and followed by uncontrolled burning. Citing the deep-rooted consequences, open dumping should be absolutely abandoned and scientific interventions should be aggressively exercised to reclaim the municipal brownfields. The present research work undertook the judicial task of assessing the comparative feasibility of biomining and scientific capping as a technology selection for reclamation of about a decade old 120 million tons of waste chunk laying at Jawahar Nagar dump yard. Primary dump samples were collected from various locations, considering depth as a variable. While leachate and groundwater samples were collected from Malkaram lake and preinstalled borewells receptively. Additionally, the ambient air quality and noise level also been ascertained within the buffer zone. The blended representative solid sample was segregated using a 70 mm mesh size trommel into organic and inorganic fractions. The organic fraction was composted using a lab-scale aerobic static pile composting (ASPC) while the trommel reject was processed as refuse derived fuel (RDF). Evidently, the compost lagged quality and depicted nutrient deficiency. While the burning of RDF produced siloxane gas, significantly due to elevated silicon level in the primary waste. Furthermore, due to the prolonged leaching tenure and seasonal dilution, the concentration of legacy leachate was relatively weaker. Borewell samples collected from a depth of 20 feet also portrayed minor contamination up to 500 meters horizontal radius. The issue of leachability can solely be resolved with the capping of the existing dump and the end product quality derived from the biomining process is highly questionable. Thus, handling such large quantity capping is a befitting option over biomining for Jawahar Nagar dumpsite. INTRODUCTION Presently, in India due to rapid urbanization and industrialization, the generation of MSW has been increasing tremendously and also expected to continue a similar trend in the future (Scott, 1995; Bhat et al., 2017; Sethurajan et al., 2018; Sharma et al., 2018). Annually, the comprehensive urban MSW generation in India is more than 62 million tons. Metro cities are the mammoth contributor of the entire chunk and waste production had already reached an alarming figure of 50,000 tonnes/day. While the waste generation from the tier 2 cities is also rigorously escalating and presently contribute up to 20,000 tones/day (Sharma et al., 2018). A study conducted by the central pollution control board (CPCB) revealed MSW generation in India is increasing at a distressing rate of 5 % per annum with a sharp escalation in the quantities of domestic hazardous waste (Sharma et al., 2018). With major financial constraints, inefficacy of collection, treatment, and disposal incurs further reasons to worry. So far India has miserably failed to set up wholesome source segregation and collection method. Presently, the country spends more than 60% of its annual waste management budget only in collection. Besides, only 20% or less of the collected materials are scientifically handled and treated. Citing the statistics, it is evident that the majority of the MSW is simply gets dumped on the low laying grounds located somewhere on the outskirts of the cities. The precipitation, infiltration, surface water runoff, bird menace, rodent interference etc. triggers the vulnerability of waste and leads to mal odor, ground and surface water contamination, human and environmental health deterioration (Jayawardhana et al., 2016). Further, the perseverance of the inorganic and inert fractions leads to soil contamination, poses a fire threat, and also may incur carcinogenicity and acute toxicity among the animals (Mir et al., 2021). There are numerous techniques for the reclamation and remediation of the dumpsites, includes processes such as capping and closure, in-situ vitrification, sub-surface cut-off walls, and waste biomining (Chakrabarti and Dubey, 2015; Thakare and Nandi, 2016). Waste biomining is a stable way to get rid of the entire range of problems associated with open dumping and reclaim valuable land (Kaksonen et al., 2017). There are several instances including reclamation of Mumbai Gorai dump yard by IL & FS Environment, 70 – 80 years old 12,00,000 tons of dump clearance by Nagar Nigam Indore within a minute span of 3 years and many more. But the process of biomining is highly sensitive and case-specific. The success of the process solely depends on factors such as characteristics of the waste, efficacy of the effective microorganism culture, acceptability of the processed end product at the local market etc. (Jerez, 2017; Banerjee et al., 2017; Venkiteela, 2020). Contrarily, though the scientific capping is not an end-to-end solution but still advisable in the cases where the quantity of waste is gigantic, land scarcity is prevalent, no nearby industries to consume the end products etc. Mehta et al. (2018) have also supported the above claim based on the assessment of locations specific MSW dump reclamation case studies. While in another Nagpur-based case study conducted by Ashootosh et al. (2020) reported the superiority of the biominingprocess over simple land capping due to the favorability of the local conditions. Capping eliminates the environmental interference and thereby reduces biosphere contamination and leachate generation. Further, it captivates rodent and vector breeding and thereby curtails the spreading of communicable diseases and improves aesthetics. But right consolidation through compaction and execution is utmost necessary in the above case. As non-compaction and faulty sloping will easily lead to heavy settlement and slope failure (Berkun et al., 2005; Al-Ghouti et al., 2021). The present study has been pursued with the primary objective to run a techno-commercial assessment between scientific capping and biomining. While the secondary objective was to ascertain the level of contamination and propose mitigative measures. MATERIALS AND METHODStudy Area Spanning over 350 acres of a precious piece of land at the outskirts of Hyderabad city, Jawahar Nagar dumping yard was brutally utilized by the Greater Hyderabad Municipal Corporation (GHMC) for open dumping for a prolonged tenure of 10 years. It housed nearly 12 lakh metric tons of heterogeneous solid and domestic hazardous waste and continues polluting until 2015, until the Ramky group was offered to cap the legacy dumping and scientifically handle the site. The present study has been facilitated at Hyderabad Municipal Solid Waste Limited, formerly known as Jawahar Nagar dump yard to analyze and assess the feasibility of bio-mining as handling and management alternate to the existing practice of scientific capping. The epicenter of processing and disposal facility is lying approximately on the cross-section of 17°31'24.45"N and 78°35'23.37"E. As per the contract, the comprehensive legacy dumping to be capped in three phases over about 150 acres of area and Ramky has significantly entered the phase two of the operation only within a span of five years by successfully capping more than half of the legacy footprint. Sampling Methodology The waste pile was divided into three layers namely, base, middle, and top. A uniform amount of sample was collected from the successive layers of all five different corners which cover north, south, east, west, and central of the garbage pile. Sampling inspections were performed using a manual auger besides large samples were collected using a JCB excavator. The top six-inch layer of the pile was removed to avoid any contamination while collecting the samples and 5-10 kg of sample was collected from each of the locations. Further, intermediate and bottom layer samples were collected by digging a 500 mm diameter hole through the heap. A composite was prepared by a homogenized blending of all the fifteen grub samples. The blend was distributed into four equal quadrants and the top and bottom quadrants were eliminated diagonally while the left-over quadrants were mixed thoroughly. This process was repeated until a sample of the required bulk of 20 kg is obtained. Surface and subsurface water samples from borewell were collected in and around the facility. Piezometric monitoring borewells located near the landfills were utilized for the subsurface sample collection. While a rainwater pond turned leachate lake named Malkaram was determined as the primary source for leachate collection. Buffer samples were collected from Ambedkar Nagar, the nearby colony exiting at a distance of only 300 meters. Lab-scale Experimentation The representative sample was characterized for composition and further screened through a 70 mm mesh size trommel. The trommel permeate was considered as the organic fraction while the reject was mostly inorganics and inert. The organics were subjected to ASPC. The quantity of the air required is arrived using the method delineated below (Figure 1). MSW Pile size: 2m x 0.5m x 0.5m Volume of pile: 0.5 m3 Average Density of MSW: 620 Kg/m3 Weight of pile: 310 Kg Nitrogen required for matured compost: 9300 mg/kg dry : 9300 X 310 mg : 2.88 x 106 mg : 2.88 Kg Total air required: 2.88 x 100/76 [as Nitrogen in air is 76% by weight] : 3.79 Kg of dry air : 3.79/1.225 m3 [@ 15 deg C density of air 1.225 kg/m3] : 3.1 m3 This air is to be supplied for 100 min / day for 0.5 m pile Air flow rate required: 3.1 x 60/100 = 1.86 m3/h (for practical purpose a flowrate of 2 m3/h was maintained). The maturation period was considered as 28 days and post-maturation, the stabilized material was further cured for 24 hours and screened using 12 mm and 4 mm trommel respectively to obtain the desired product quality and particle size. Whereas, the trommel reject was evenly spreader on the copper trays and dried in an oven at 1050C for 2 hours. The dried material was micronized to the size of 50 mm or below using a scissor and inert such as glass, sand, stone etc. were segregated manually (Mohan and Joseph, 2020). Concurrently, a bench-scale capped landfill prototype was built using the below-mentioned procedure to evaluate the factors such as settlement and slope stability. A 30 mm thick low permeable soil was laid on the top of the waste, followed by a 60 mm layer of compacted clay liner (CCL). Each join between successive liner material was closely monitored. A 1.5 mm thick HDPE liner was placed on the top of the CCL. A 285 GSM geotextile membrane was placed as the successive above layer followed by a 15 mm thick drainage media layer. A further layer of geotextile membrane was placed on top of the drainage media for better stabilization, grip, and strength. The top vegetative soil layer of 45 mm thickness was laid off on top of the geotextile media and St. Augustine grass was rooted (Cortellazzo et al., 2020; Ashford et al., 2000). 2.4 Sample Analysis pH, Electrical Conductivity (EC) and Turbidity of the samples were analyzed using pH, EC-TDS, and Nephelometer of Mettler Toledo. The pH meter was calibrated with the buffer solution of 4.0, 7.0 & 9.12 at a controlled temperature. EC-TDS meter was calibrated with 0.1 M KCL having 12.8 mS/cm of conductivity. Nephelometer was calibrated with Formazine solution of 10 & 100 NTU. Total Dissolved Solids (TDS), (mg/L) was performed using the gravimetric method at 1800C in the oven. Titrimetric parameters such as Total Alkalinity as CaCO3 (mg/L), Total Hardness as CaCO3 (mg/L), Chloride as Cl- (mg/L), Calcium as Ca2+ (mg/L), Residual Free Chlorine (RFC), (mg/L) were analyzed using APHA (American Public Health Associations) method, 23rd Edition, 2017. Total Kjeldahl Nitrogen (mg/L) and Ammonical Nitrogen (mg/L) were performed through distillation followed by titration with H2SO4 as a titrant. Sulphide as S2- was done with the Iodometric method after distillation. Each titrimetric parameter was analyzed in triplicate after standardizing the titrant with required reagents and crossed checked by keeping a check standard. Sodium as Na (mg/L) and Potassium as K (mg/L) were performed using Flame Photometer. The photometer was calibrated with different standards from 10 to 100 (mg/L) standard solutions. The leachate sample was diluted enough to get the value within the standard range and cross-checked with check standards at the same time. Chemical Oxygen Demand (COD), (mg/L) was performed using the open reflux method for 2 hours at 1500C in COD Digestor. Biochemical Oxygen Demand (BOD), (mg/L) was performed using the alkali iodide azide method for 3 days. The samples were kept in a BOD incubator at 270C for 3 days. It was kept in duplicate to have a check on quality control. Sulphate was analyzed by the gravimetric method instead of turbidimetric or through UV-Visible spectrophotometer as its concentration was found more than 40 mg/L. Nitrate as NO3- was analyzed after filtration at 220-275 nm, while Hexavalent Chromium as Cr6+ was analyzed at 540 nm in the UV-Vis. Parameters like Cyanide as CN-, Fluoride as F-, and Phenolic Compounds were gone through a distillation process followed by UV-Vis. The distillation process ensures the removal of interferences presents either positive or negative. For the parameters like Total Iron or Ferric Iron, the samples were digested properly with the required reagents on the hot plate before analyzing in UV-Vis. For the metal analysis the water samples were digested at a temperature of 1000C using aqua regia as a media. The samples were digested to one-fourth of the volume on a hot plate. The recommended wavelengths as per APHA 3120 B were selected for each of the metals. The standard graph was plotted for each of the metals before analysis and crossed checked with the check standard at the same time. Parameters such as bulk density and particle size were performed through the certified beaker and sieve. The percentage of moisture content was estimated using the oven by keeping the compost sample for 2 hours at 1050C. C/N ratio was estimated through CHNS analyzer keeping sulfanilamide as a check standard. The analysis was performed by extracting the desired component in the desired solution prescribed in the method followed by converting the same from mg/L to mg/Kg. RESULTS AND DISCUSSION An exhaustive bench-study has been pursued and real-time samples were collected and analyzed for all possible parameters to determine the pros and cons attributed to both processes. The investigation begins by collecting the samples and concluded by impact assessment studies inclusive of the buffer zone. Both solid, liquid, and gaseous samples were precisely investigated to opt for the best solution. A detailed finding of the investigation is summarized below. Primarily, the representative solid sample was characterized through a manual separation process and the results are portrayed in Figure 1. Compost Characterization ASPC of the organic fraction has resulted in a recovery of 46.7% of the initial load. While 53.3% of the influent mass were inert and barely degradable fraction contributes to reject, the rest 4.1% is miscellaneous process loss. The processed compost was extensively analyzed including for metal contamination and the same is tabulated in Table 1. The value of C/N ratio, OC, TN, K2O, P2O5, and NPK evidently portrays the shortcoming in terms of nutrient availability. Though it is highly enriched in organic carbon and thus the same can be effectively utilized as a soil preconditioner. Ayilara et al. (2020) also reported a similar finding, where the city compost sourced from MSW lagged major plant nutrients. RDF Characterization Processed trommel rejects constitute cloth, rexine, leather, jute, paper, plastics, coir and other inert contributed to RDF. The fraction of inert was as high as 37.2% of the overall RDF mass and it mostly constituted glass and sand. The combined weight of sand and glass fragments contributed 73.5% of the total inert, while the rest was stone and small brickbats. The higher level of silicon associated with the presence of glass and sand yielded siloxane and triggered the possibility of kiln corrosion. A detailed RDF analysis report is enclosed in Table 2. The values explicitly portray the quality of RDF is moderately lower and higher salts concentration is extremely prevalent. With relatively lower NCV and such high salt concentration, the above specimen will certainly pose a corrosion threat to the kiln and shall be either neglected as kiln feed or can be utilized after dilution with Grade III RDF quality. Further, such high ash generation will also induct high transportation and landfill charges. Leachate Characterization The Malkaram leachate lake is the end result of prolonged, slow, and steady mixing of the legacy leachate through the existing fissure cracks in the sheath rock bottom profile. Apparently, the concentration of leachate is significantly lower due to the dilution. Samples were analyzed in triplicates and the mean value is tabulated here in Table 3. The metal concertation and rest of the parameter values are well within the secondary treatment influent range, except for TDS. Thus, a modular aerobic biological treatment unit such as moving bed biofilm bioreactor (MBBR) or membrane bioreactor (MBR) would be a well-suited pick. However, a reverse osmosis (RO) system needs to be installed to get rid of the high TDS content. The permeate of RO can be reused back into the system. Whereas, the reject can be converted into dried powder through forced evaporation mechanisms. The higher concentration of salts in RDF collaterally justifies the elevated TDS level in leachate. In a leachate impact assessment study performed by El-Salam and Abu-Zuid (2015) the reported BOD/COD ratio of 0.69 is greater than double the value of 0.301 reported in Table 3. Though the difference in both the values are quite high, it is relatable and justifiable by the huge age difference of the source waste. The primarily characterized data is of a fresh leachate generated from regular MSW, while the later one is from a decade old waste that barely has any unstabilized organic content. Groundwater Contamination The obvious reason for downward leachate infiltration and osmotic movement facilitates groundwater contamination. Both surface and subsurface water samples were collected within the dump yard and the buffer zone and analyzed using the standard methods. The results are portrayed in Table 4. The slightly alkaline pH of the borewell sample is an indication of the ongoing anaerobic process. The dissolved oxygen value of 3.5 mg/L further validates the correlation. Higher TDS and hardness values are self-indicative of elevated salt concentration in source waste. Eventually, the same interfered with the RDF quality. Positively in the case of all the parameters, a successive decrement in pollution concentration has been spotted from dump ground towards the buffer zone. In a similar study conducted by Singh et al. (2016) at Varanasi, Uttar Pradesh the reported concentration of the parameters is significantly higher than reported in Table 4. The basic reason behind variation is the dissimilarities of the local soil profile. The sandy and clay loam soil profile of Varanasi allows a greater rate of percolation and infiltration. While the bottom sheath rock profile at Jawahar Nagar permits the only a minute to little percolation rate. The difference in percolation rate is directly correlated to the concentration levels in this case. Contrarily, Kurakalva et al. (2016) have reported much-elevated pollutant concertation both in ground and surface water for a study conducted at the same site in 2016. The higher concentration is relatable to the fact of the non-closure of the open dump back then. Capping activity had at Jawahar Nagar gained its pace 2018 onwards and capping for the primary section of 70 acres got concluded only during mid of 2019. Due to the decrement in runoff and percolation, the quality of both surface and subsurface water has improved drastically. Impact Assessment The odor and groundwater contamination are two of the primary issues that triggered a massive public agitation initially. The root causes of both the issues are identified as rainwater percolation and anaerobic digestion respectively. Eventually, the completion of the capping process would resolve both the problems effectively. Other non-tangential impacts include nausea; headache; irritation of the eye, nasal cavity, and throat; diarrhoeal diseases; vector-borne disease, cattle toxicity etc. Scientific capping can easily cater as the wholesome solution for all (Cortellazzo et al., 2020). Yu et al. (2018) had performed an extensive study to comprehend the relativity of respiratory sickness and MSW borne air pollution. The study made a couple of dreadful revelations such as gases released due to the anaerobic digestion of MSW such as methane, hydrogen sulphide, and ammonia incur detrimental impact on Lysozyme and secretory immunoglobulin A (SIgA). While SO2 was reported as the lung capacity and functionality reducer. Further, a gender-specific study executed by the same research group revealed, air pollution impacts more severely on male children than the female and retards immune functions. Presently, the area of 351 acres has been developed as Asia’s one of the largest state of the art municipal solid waste processing and disposal facility by Ramky Enviro Engineers Limited. This ensured zero dumping and no further environmental interventions. As legal compliance, the facility monitors the quality of groundwater and ambient air quality in and around the facility on monthly basis to assure the biosafety. The variation in concentration of various monitoring parameters between 2012 to 2020 is summarized in Figure 2. The concentration of each of the parameters are showcased in ppm and a standard equipment error was settled at 3% for respirable dust sampler and multi-gas analyzer (Taheri et al., 2014). Despite all parameter values have gradually increased except for methane, the facility still managed to maintain them well under the regulatory limits. The decrement in methane concentration is directly correlated to the practice of aerobic composting and aeration-based secondary treatment that prevented the formation of the anaerobic atmosphere and henceforth methane generation. While for the rest of the parameters the increment in values is quite substantial and predictable due to the sudden escalation in MSW generation in the past decade in correlation with Gross domestic product (GDP) enhancement. The observed and interpreted impacts due to the elevated pollutant level are in-line with the georeferenced findings reported by Deshmukh and Aher (2016) based on a study conducted at Sangamner, Maharashtra. CONCLUSION The study critically analyzed and investigated every techno-environmental and socio-economic aspect correlated to open dumping. The bench-scale experimentation revealed the efficiency of the single liner scientific capping is fair enough to eliminate any further rainwater infiltration, however, it has no control over the generation of leachate due to the inherent moisture. Internal moisture related issue was anyhow compensated with pertinent compaction prior to dispose of the waste. Contrarily, both the products derived through the biomining process namely, compost and RDF lagged quality due to scantier nutrient content and higher salt and silicon content respectively. Besides, impact assessment studies concede the pollutant concentration in groundwater in and around the plant has drastically diminished post-July 2019 due to the partial completion of waste capping. It also abetted lowering the dust and odor issues relatively in the surrounding. ACKNOWLEDGMENT The authors would like to sincerely acknowledge GHMC, Hyderabad Integrated Municipal Solid Waste Limited, and Ramky Enviro Engineers Limited for enabling us to pursue the sample collection and other necessary onsite activities. Further, the authors would like to register profound acknowledgment to EPTRI for supporting us with the essential experimental facilities. REFERENCES Sharma, A., Gupta, A.K., Ganguly, R. (2018), Impact of open dumping of municipal solid waste on soil properties in mountainous region. 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This paper investigates the effects of local porous uniform blowing on the skin-friction drag reduction in the spatially developing compressible turbulent boundary layers through direct numerical simulations. Under the influence of uniform blowing, the skin-friction drag decreases drastically within the controlled regions, and the effect extends downstream. The drag reduction rate exceeds 10% for the uniform blowing velocities considered herein. The intrinsic mechanism of decreased skin-friction drag is further explored, in terms of the various contributions to this quantity, the Reynolds shear stress budget, and the multi-scale distributions and transfer of enhanced turbulent motions. The numerical results for the identity of Renard and Deck ["A theoretical decomposition of mean skin friction generation into physical phenomena across the boundary layer," J. Fluid Mech. 790, 339-367 (2016)] indicate that the decreased skin-friction drag is reflected in a negative contribution in the streamwise developing direction. The enhanced turbulent motion is investigated through the Reynolds shear stress budget, and uniform blowing is found to strengthen the magnitudes of all budget terms. We conclude that uniform blowing promotes the energy cascade process in the near-wall region, promoting the appearance of smaller turbulent structures and the formation of large outer scales. Similar skin-friction drag reduction in the subsonic case is also observed in a supersonic case. The upstream transition process is delayed, which leads to a relatively larger skin-friction drag reduction rate in a supersonic case. Finally, we investigate the porosity effects on the skin-friction drag, and conclude that the blowing flux is a decisive factor.

Les dynamiques temporelles et spatiales des échanges entre les surfaces continentales et l'atmosphère sont en grande partie contrôlées par la végétation. Dans un contexte de changement climatique, la précision de la modélisation des bilans d'énergie, d'eau et de dioxyde de carbone des écosystèmes dans les modèles de surfaces continentales revêt ainsi d'un double enjeu : elle permet d'améliorer la représentation des échanges entre les surfaces et l'atmosphère et, par conséquent, d'améliorer la fiabilité des modèles de climats ; et elle permet également de comprendre et de quantifier l'impact du changement climatique sur le fonctionnement des écosystèmes végétaux. Dans la majorité des modèles, la structure de la végétation est simplifiée, considérée équivalente à une surface d'épaisseur infinitésimale échangeant de l'eau, de l'énergie et des composés avec l'atmosphère (modèle de type "grosse-feuille"). La dynamique complexe des échanges au sein des écosystèmes végétaux, et particulièrement des forêts, incluant le microclimat intra-canopée, reste très mal ou pas représentée dans les modèles actuels. Ce microclimat joue cependant un rôle important dans la régulation des échanges d'énergie et de masse entre la végétation et l'atmosphère et son évolution dans un contexte de changement climatiques est méconnue. Cette étude présente les premières étapes effectuées dans le modèle ORCHIDEE (composante de surface du modèle de climat de l'IPSL) pour l'étude de ce microclimat intra-canopée à l'échelle globale. La représentation simpliste de type "grosse-feuille" utilisée dans ORCHIDEE est remplacée par un modèle d'échanges d'eau et d'énergie au sein de la canopée (suivant une discrétisation verticale). L'intégration de ce modèle est effectuée en deux étapes. La première s'attache à la représentation du transport de l'eau dans le continuum sol-plante-atmosphère et a pour objectif de contraindre les échanges feuille-atmosphère grâce à l'état hydrique de la végétation. Ce travail s'appuie sur une représentation du potentiel hydrique dans les différents compartiments de la plante (i.e. architecture hydraulique). Cette intégration est étudiées de manière détaillée à l'échelle du site avant une étude d'impact globale. La seconde étape consiste à la mise à jour, la mise à niveau et l'amélioration d'un modèle d'échanges d'eau et d'énergie multi-couches entre la végétation et l'atmosphère précédemment implémenté dans une branche d'ORCHIDEE. L'évaluation de ce modèle est effectuée à l'échelle des sites forestiers en comparaison du modèle d'écosystèmes MuSICA sur une base de données crée à cet effet. La comparaison des gradients de température intra-canopée simulés et observés est très encourageante. Elle a aussi permis d'identifier des pistes pour l'amélioration globale du modèle. Enfin, des perspectives sont discutées pour une utilisation de ces modèles à l'échelle globale et notamment pour simuler l'évolution du microclimat sous une canopée forestière en fonction du changement climatique et des pratiques forestières
The temporal and spatial dynamics of exchanges between continental surfaces and the atmosphere are largely controlled by vegetation. In the context of climate change, accurately modeling the energy, water, and carbon dioxide balances of ecosystems in land surface models presents a dual challenge: it improves the representation of exchanges between surfaces and the atmosphere, thereby enhancing the reliability of climate models; and it also helps to understand and quantify the impact of climate change on the functioning of plant ecosystems. In most models, the structure of vegetation is simplified, treated as equivalent to an infinitesimal thickness surface exchanging water, energy, and compounds with the atmosphere (a "big-leaf" model). The complex dynamics of exchanges within plant ecosystems, particularly forests, including the intra-canopy microclimate, remain poorly represented or not represented at all in current models. However, this microclimate plays a crucial role in regulating energy and mass exchanges between vegetation and the atmosphere, and its evolution in the context of climate change is not well understood. This study presents the first steps taken in the ORCHIDEE model (the land surface component of the IPSL climate model) to study this intra-canopy microclimate at a global scale. The simplistic "big-leaf" representation used in ORCHIDEE is replaced by a model of water and energy exchanges within the canopy (following vertical discretization). The integration of this model is carried out in two stages. The first focuses on representing water transport in the soil-plant-atmosphere continuum and aims to constrain leaf-atmosphere exchanges based on the water status of the vegetation. This work relies on a representation of water potential in the different compartments of the plant (i.e., hydraulic architecture). This integration is studied in detail at the site scale before conducting a global impact study. The second step involves updating, upgrading, and improving a multi-layer model of water and energy exchanges between vegetation and the atmosphere previously implemented in a branch of ORCHIDEE. The evaluation of this model is conducted at the scale of forest sites in comparison to the MuSICA ecosystem model based on a database created for this purpose. The comparison of simulated and observed intra-canopy temperature gradients is very encouraging. It has also helped to identify avenues for the overall improvement of the model. Finally, prospects are discussed for using these models at a global scale, particularly to simulate the evolution of microclimate under a forest canopy in relation to climate change and forestry practices

Abstract The accurate modelling of secondary-flow dynamics is a key aspect of reliable performance predictions for turbomachinery. This is due to the effect of secondary flow on the aerofoil boundary layers, as well as the overall energy budget. In this paper, we assess the predictive performance of a vortex-reactive turbulence-model extension using integral performance data of a multi-stage compressor test rig. The model extension provides a more accurate prediction of multi-stage compressor characteristics, especially if cavities and squealer tips are considered. This is achieved by mitigating an underprediction of near-choke mass-flow rates, and of the total-pressure ratio and isentropic efficiency near stall. The analysis shows that this is achieved by affecting the formation and propagation of secondary flow.