Evaporation Of Rainwater Research Articles

MISS from a temperate hypersaline saltpan under continental influence (Salitral de La Vidriera, Argentina)

The Salitral de La Vidriera (SDV; 38°44′S, 62°34′W) once occupied the innermost section of a funnel-shaped estuary before its isolation due to sea level drop ∼3000 years BP. It currently is a continental saltpan detached from the Bahía Blanca estuary, having no marine connection, and acting as a hypersaline evaporitic environment. This study provides a first-hand characterization of the epibenthic microbial mats that biostabilize surface sediments in the saltpan, and the environmental dynamics and physical deformation agents behind the formation of modern Microbially Induced Sedimentary Structures (MISS). The microbial community in the hypersaline mats is dominated by cyanobacteria of filamentous (taxonomic order Oscillatoriales) and coccoid morphologies (orders Chroococcidiopsidales and Pleurocapsales). The MISS comprise rolled-up mats, flipped-over mats, folds and wrinkles, reticulate surfaces, gas domes, pinnacles, and desiccation cracks; their genesis is linked to the presence of water that either promotes microbial growth or creates hydrodynamic deformation structures. Gypsum crystals were found in surface and subsurface sediments plausibly linked to a high rate of rainwater evaporation and aided in their preservation by the microbial mat lattice. Furthermore, carbonate precipitation in the form of peloids was identified through petrographic analysis, despite the siliciclastic nature of sediments. The occurrence of modern MISS in this transitional environment, currently under continental influence, is discussed and contrasted with modern peritidal environments. Descriptions from this study, contextualized in a modern depositional setting, may be useful in the study of fossil counterparts and paleoenvironmental reconstructions.

Uso de herramientas hidroquímicas e isotópicas para evaluar el rol del agua subterránea en el funcionamiento hidrológico de una laguna Pampeana, provincia de Buenos Aires, Argentina

Waters from the fractured-karstic and detritic (Pampeano) aquifers, and from surface water bodies are closely interacting in the Tapalqué Creek Upper Basin (CSAT for its acronym in Spanish), southeast of the Chaco-Pampean plain, Argentina. The La Barrancosa lake, endorheic and of socio-economic and cultural relevance, is located in this basin headwater. Within the framework of an integrated vision of these water resources, the main objective of this work is to know this lake’s water origin, as well as to identify and explain the processes involved in its interaction with the Pampeano aquifer. Hydrochemical and isotopic (δ2H and δ18O) tools were jointly used, with special emphasis on the ionic ratios study and the hydrochemical modelling. The rainwater evaporation during infiltration into aquifers and the dissolution/weathering of the geological materials rich in Ca2+, Mg2+ and K+ present in the study area, are the main processes that determine the composition of waters in the recharge zones. The dissolution of Na+-rich minerals and the cationic exchange are of relevance toward the plain zone. This last process and the concentration by evaporation control the composition of the La Barrancosa lake waters (effluent). These conclusions are validated by the δ2H, δ18O and d values characteristic of the CSAT waters and can be extrapolated to other basins developed in similar environments.

Formation and evolution mechanisms of a destructive-wind-producing thunderstorm in Shanghai

The formation and evolution mechanisms of a destructive-wind-producing thunderstorm that occurred in Shanghai were studied using a Weather Research and Forecasting model simulation. To understand the formation mechanisms of the severe winds, we separately analyzed the downdrafts and accelerations of horizontal winds by zonal and vertical momentum tendencies. Also, the effects of temperature and humidity on the thermodynamics and cloud microphysics were diagnosed. It was found that wind gusts with large horizontal extent and strong wind speed mainly occurred during the maturation stage, and then widespread severe winds still maintained when the storm entered the decaying stage. Analysis also showed that the meridional advection of the zonal wind gradient and rainwater evaporation, which was significantly enhanced by the melting of graupel aloft, were the main factors causing the severe winds during the maturation stage. In the decaying stage, meanwhile, the accelerations of horizontal winds associated with cold pools accompanied by the large horizontal perturbation pressure gradient force and widely distributed drag force of rainwater were the main factors that maintained the large extent of severe winds near the surface.

The Impacts of Hydrometeors and Water Vapor in Stratiform Region on the Evolutions of MCSs and Embedded Convective Cells in a Pre‐Summer Rainfall Event Over South China

AbstractBoth the stratiform and convective regions play important roles in the development of mesoscale convective systems (MCSs). In this study, the impacts of hydrometeors and water vapor in stratiform region on the evolution of MCSs during a heavy rainfall event over South China are investigated by the Weather Research and Forecasting (WRF) model with Thompson microphysics. A series of sensitivity experiments including the reductions of water vapor to 95%, 80% (water vapor sensitivity experiments), and the reductions of hydrometeor mixing ratios to 10% (hydrometeor sensitivity experiments) in stratiform region are conducted, respectively. Results show that the control run reasonably reproduces the spatial distribution and temporal evolution of convective rainbands. The hydrometeor flux convergence partly indicates the changes of convection organization and movement direction. The intensities of precipitation and MCSs are significantly weakened by decreasing moisture advection to convective region in water vapor sensitivity experiments, but are a little weaker in hydrometeor sensitivity experiments. The enhanced water vapor advection and reduced sedimentation and evaporation of rain water in hydrometeor sensitivity experiments are responsible for the restoration of stratiform cloud. The stratiform region with more hydrometeors is generally more conducive to the development of convection than less one when they are at the same evolution stage. However, it is found that stronger convective cell can also exist in the stratiform region with less hydrometeors that is generated by the old convection cloud and at its dissipating stage, owing to the more transfer of water vapor and hydrometeors from stratiform to convective regions.

Sub-Hourly Variability of Stable Isotopes in Precipitation in the Marginal Zone of East Asian Monsoon

Isotope data at mid-latitude locations are commonly available on annual, monthly, and daily timescales; however, they are rarely available for the variations occurring on the sub-hourly scale within individual precipitation events. To fill this gap, sub-hourly (every 10 min) sequential samples were collected for nine precipitation events, and the δ18O values of the individual events were analyzed from June to October 2019 in Lanzhou, Northwest China. The Sequential Meteoric Water Line (SMWL) correlation between δ2H and δ18O is δ2H = 7.33 δ18O + 9.78 (R2 = 0.97, N = 170). All events had a similar decreasing variability pattern in the initial period (before the vertical gray dotted line), while during the later period (after the vertical gray dotted line), negative δ18O values dominated, exhibiting a different pattern. Variations in the δ18O values were about 1–5‰ during most intra-events. We found that δ18O values mainly exhibit three patterns in the intra-event, namely a “V”-shaped pattern, an “L”-shaped pattern, and a decreasing pattern. Positive δ18O values are controlled by re-evaporation in the beginning period. Relative humidity has no effect on the δ18O values of precipitation events, mainly because dry and warm conditions are conducive to the evaporation of rainwater in the study region. The changes in the isotopic characteristics of precipitation are closely linked to the regional climate. The continuous analysis of precipitation samples revealed that the rapid change of δ18O values is related to different moisture sources and transport paths. A new air mass with enriched heavy isotope intrusion can change the isotopic composition in the intra-event.

생태건축에서 물순환 확보를 위한 관련규정 개선 : 빗물이용 현황분석을 중심으로

Purpose: It was analyzed in this study what measures were applied to promote the water cycle to build ecological architecture. Based on this results, it would be to suggest what items should be supplemented in addition to the use of rainwater to secure water circulation in ecological construction. This aims to analyze how relevant the these guidelines are to the status of the facilities, and how effective the rainwater facility is in the water cycle. Method: The regulations and guidelines related to green city and green building certification were analyzed, and the application status of 251 rainwater use facilities in Korea was analyzed. In addition, it was reviewed that the water circulation-related evaluation items on DGNB which is a sustainable architecture evaluation system in Germany, and it was analyzed the cases of realization of them in architectural architecture. Result: In conclusion, the method of promoting water circulation in ecological construction is not only to use rainwater in terms of water conservation but also to induce more integrated rainwater evaporation, infiltration, storage. This protects the groundwater, effectively uses water and reduces the load on sewer pipes.

Influence of anthropogenic emissions on wet deposition of pollutants and rainwater acidity in Guwahati, a UNESCO heritage city in Northeast India

Abstract Guwahati, the largest urban corridor of Northeast India, is one of the United Nations Educational, Scientific and Cultural Organization (UNESCO) world heritage sites and one of the 200 eco-regions in the world. The present study investigates the characterization of chemical components and sources of precipitation samples collected in Guwahati during June 2016–June 2017. Acidic rain events occurred throughout the year, with a frequency of 64% and 87% during monsoon and non-monsoon seasons, respectively. Higher contributions of the acidic species (SO42− and NO3−) coinciding with poor neutralizing capacity of crustal species (Ca2+, K+ and Mg2+) led to acid rain in this region. Isotope analysis (δ18O and δD) indicated that monsoonal and non-monsoonal rains were of marine and non-marine origins, respectively. This is further supported by the back trajectory analysis as majority of the individual rain events during d-excess 10‰ i.e. non-monsoon, the trajectories originated from water-inland. The enrichment factors (EF) for Pb, Zn, Co and Cu were >5, indicating the dominance of anthropogenic sources in this region. The Positive Matrix Factorization (PMF) along with isotope analysis identified marine (40%) as the major source in monsoon and industrial emissions (28%) in non-monsoon, indicating rainwater evaporation is more of ocean and continental origin during monsoon and non-monsoons, respectively. This study suggests the need of further studies and implementation of stringent anthropogenic regulations not only in local but also at regional and global scale, in this acid rain prone region.

Analysis of the effect of impermeability of urban soils on the infiltration of rainwater in the city of Recife, PE

The process of urbanization interferes in the elements of the hydrological cycle, altering the infiltration, flow, and evaporation of rainwater. Several methods and tests exist for analyzing this hydrological cycle that aim to hydrodynamically characterize the soil of a locality. However, the collection and field trials can be expensive and time consuming. Because of these high costs, it is important to look for methods that save time and money. One such method is to perform simulations of water flow in the soil, using computational models such as Hydrus 1-D, in order to explain the water balance of a region. The results of these simulations showed that 355.18 mm.m-2 of the total 385.02 mm.m-2 of precipitation was able to infiltrate, indicating that the soil of the region has a high infiltration capacity, due to its high sand content. However, of the 228,000 m2 studied, only 38,760 m2 are unpaved soil. This shows that the soil at the location studied would be able to infiltrate most rainwater without the occurrence of flooding, if more than only 17% of the land area were permeable soil. This conclusion can be extrapolated to other areas surrounding this neighborhood and to other large urban centers, which have similar characteristics.

A self-powered flexibly-arranged gas monitoring system with evaporating rainwater as fuel for building atmosphere big data

The atmosphere big data technique can provide data support for scientific decision-making for industry and people's life. Here, a novel self-powered flexibly-arranged gas monitoring system has been presented basing on a new water-evaporation/gas-sensing coupling effect. The rainwater evaporation along the device can convert natural energy into electricity for powering the whole system. And the outputting voltage/current is significantly dependent on the environmental atmosphere, acting as the gas sensing signal. The surface functional groups of carbon can bind to gas molecules, which changes the zeta potential of carbon and thus affects the electric output. The self-powered gas monitoring systems can be flexibly fixed out of doors, actively detect the air quality of different locations, and wirelessly transmit the sensing information to external platforms for building big data. The present results can open a new possible research direction for self-powered gas sensor and will further promote the development of environmental big data.

A Study of Cloud Microphysical Processes Associated With Torrential Rainfall Event Over Beijing

AbstractThe evolution of mesoscale convective systems (MCSs) leading to a heavy rainstorm event that occurred in Beijing on 21 July 2012 was simulated using the Weather Research and Forecasting model. Observational analyses indicated that this event can be divided into an earlier‐occurring warm‐sector precipitation (WSP) and a later‐occurring cold‐frontal precipitation (CFP). Owing to the considerable differences in their ambient weather conditions, the features and evolution of the cloud microphysics were different. Diagnoses of the mass‐ and heat‐hydrometeor budgets showed that the major differences in rainwater source were that the graupel melting (PGMLT) and the collection of snow by rain (PRACS_s2r) had similar magnitudes in the WSP, and PGMLT was larger than PRACS_s2r in the CFP, while the accretion growth of cloud droplets (PRA) was always the largest in both phases. The main cooling effect in the WSP was due to the evaporation of rainwater (PRE) and cloud water, while it was PRE and PGMLT for the CFP. The mechanisms of how microphysical processes influenced the precipitation were explored. It was found that the strong PRA in the WSP was conducive to the formation of a supercooled water level and evoked a seeding effect. However, graupel processes were crucial for the CFP. The strong sublimation processes of graupel and snow associated with the collection of droplets by graupel caused more latent heat release and drove airflow to reach a higher convection height. Moreover, the stronger PGMLT cooled the air in the MCS and reduced the effect of cloud droplet accretion growth.

Helophyte mats (wetland roofs) with high evapotranspiration rates as a tool for decentralised rainwater management – process stability improved by simultaneous greywater treatment

Abstract Redensification of the housing stock is also creating challenges for the drainage of wastewater and rainwater in existing sewer systems, particularly in growing cities. One alternative here is the evaporation of rainwater, which reduces hydraulic loads on sewers. Rainwater evapotranspiration using helophyte mats on building roofs is a possible approach. Helophytes are able to transpire considerably more rainwater than extensively planted green roofs. Other than conventional green roofs helophyte mats in the form of wetland roofs require a permanent water supply on a daily basis. Greywater application can be an additional advantage in terms of nutrient supply of the wetland roof after being treated microbiologically within the plant carrier mat. The treatment of greywater using a helophyte-planted roof can help to meet the water and nutrient requirements of the helophytes even during rain-free periods. However, it must be ensured that the root mat treats the greywater to a sufficient extent. It was shown under practical conditions that a 0.1 m-thick helophyte mat is suitable for treating typical domestic greywater at loads of up to 15 L m−2 d−1.

The effects of ice microphysics on the inner core thermal structure of the hurricane boundary layer

The effects of five cloud microphysics parameterizations on the mean thermal structure of the tropical cyclone boundary layer (TCBL) are examined by numerical experiments with an axisymmetric, non-hydrostatic model. It is shown that although the radial and azimuthal velocity remains “slaved” to the gradient flow above the TCBL, the strength of the boundary layer updrafts (and downdrafts) and the location of the cloud base (which is connected to the location of the stable layer within the TCBL) depend sensitively on the microphysics parameterization. From an analysis of the potential temperature and water vapor mixing ratio budgets, it is found that latent heat release within the eyewall above the cloud base is balanced by the strong cooling tendency due to vertical advection above the cloud base. Below the cloud base, it is found that the downward flux of high θ is largely balanced by rain evaporation. Near the surface, it is shown that warm rain microphysical parameterizations enhance near-surface evaporation rates compared to their ice microphysics counterparts (which affect the thermal structure of the surface layer). Finally, it is shown that diagnostic TCBL models generally underestimate rainwater evaporation rates compared to the full non-hydrostatic model.

Low-cost production of a 7Be tracer from rainwater and purification: preliminary results

7Be with its relatively short half-life (53.22 days) is a possibly suitable radionuclide for radiotracer experiments. Low-level activities of natural 7Be can be found in rainwater and might be available as a tracer after radiochemical isolation. Herein, beryllium was first concentrated by evaporation of rainwater and/or iron(III) hydroxide co-precipitation. Afterwards, several separation schemes have been tested including various ion exchange resins in order to remove interfering other elements. Characterization was done by gamma spectrometry and inductively coupled plasma atomic emission spectrometry, respectively. With further optimizations of our methodology, rainwater may become a suitable low-cost and easily accessible 7Be tracer source.

Simulation of the evolution of the latent heat processes in a mesoscale convective system accompanied by heavy rainfall over the Guangzhou region of South China

AbstractA cloud-scale WRF simulation was used to investigate the cloud microphysical processes and three-dimensional structure of latent heat budgets in different stages of a mesoscale convective system (MCS) accompanied by heavy rain that occurred in the Guangzhou region of South China. The results enable us to draw the following conclusions: (1) During the development and mature stages, the main heating processes were condensation below 400 hPa and deposition above 400 hPa. The main cooling processes were evaporation and melting. During the dissipation stage, all the microphysical processes were weak. (2) Water vapor condensed into cloud water, and rainwater significantly contributed to all stages of the MCS. (3) During every stage of the MCS, the primary cooling microphysical process was the evaporation of rainwater, which was maximum during the mature stage.

Simulation of the Microphysical Processes and Effect of Latent Heat on a Heavy Rainfall Event in Beijing

An extraordinary rainstorm that occurred in Beijing on 21 July 2012 was simulated using the Weather Research and Forecasting model. The results showed that: (1) The two precipitation phases were based on a combi- nation of cold cloud processes and warm cloud processes. The accumulated conversion amount and conversion rate of microphysical processes in the warm-area phase were all much larger than those in the cold front phase. (2) 72.6% of rainwater was from the warm-area phase. Rainwater mainly came from the melting of graupel and the melting of snow, while the accretion of cloud water by rain ranked second. (3) The net heating rate with height appeared as an overall warming with two strong heating centers in the lower and middle layers of the troposphere and a minimum heating center around the melting layer. The net heating effect in the warm-area phase was stronger than that in the cold front phase. (4) Warm cloud processes contributed most to latent heat release, and the thermal effect of cold cloud processes on the storm in the cold front phase was enhanced compared to that in the warm-area phase. (5) The melting of graupel and snow contributed most to latent heat absorption, and the effect of the evaporation of rainwater was significantly reduced in the cold front phase.

Indian summer monsoon precipitating clouds: role of microphysical process rates

The budget analysis of microphysical process rates based on Modern Era Retrospective-analysis for Research and Applications (MERRA) products are presented in the study. The relative importance of different microphysical process rates, which is crucial for GCMs, is investigated. The autoconversion and accretion processes are found to be vital for Indian Summer Monsoon (ISM). The map-to-map correlations are examined between observed precipitation and MERRA reanalysis. The pattern correlations connote the fidelity of the MERRA datasets used here. Results of other microphysical parameters (e.g. ice water content from CloudSat, high cloud fraction from CALIPSO and MODIS, latent heating from TRMM, cloud ice mixing ratio from MERRA) are presented in this study. The tropospheric temperature from reanalysis product of MERRA and NCEP are also analyzed. Furthermore, the linkages between cloud microphysics production rates and dynamics, which are important for North–South tropospheric temperature gradient for maintaining the ISM circulation, are also discussed. The study demonstrates the microphysical process rates, which are actually responsible for the cloud hydrometeors and precipitation formation on the monsoon intraseasonal oscillations timescale. Cloud to rain water auto-conversion and snow accretion rates are the dominant processes followed by the rain accretion. All these tendency terms replicates the similar spatial patterns as that of precipitation. The quantification of microphysical process rates and precipitation over different regions are shown here. The freezing rate is also imperative for the formation of cloud ice as revealed by the observation. Freezing rates at upper level and snow accretion at middle level may have effect on latent heating release. Further it can modulate the north–south temperature gradient which can influence the large-scale monsoon dynamics. The rain water evaporation is also considered as a key aspect for controlling the low level moisture convergence (source of water vapor) in ISM. This study has highlighted the importance of detailed microphysical production rates for warm and mixed-phase cloud processes, which is a major source of uncertainty in the climate models. Better understanding of these processes will definitely add value to the present generation climate models. Therefore the hypothesis/pathway emerged from the present study may be helpful for the future model development research.

Impacts of Evaporation of Rainwater on Tropical Cyclone Structure and Intensity—A Revisit

Abstract The impact of evaporation of rainwater on tropical cyclone (TC) intensity and structure is revisited in this study. Evaporative cooling can result in strong downdrafts and produce low–equivalent potential temperature air in the inflow boundary layer, particularly in the region outside the eyewall, significantly suppressing eyewall convection and reducing the final intensity of a TC. Different from earlier findings, results from this study show that outer rainbands still form but are short lived in the absence of evaporation. Evaporation of rainwater is shown to facilitate the formation of outer rainbands indirectly by reducing the cooling due to melting of ice particles outside the inner core, not by the cold-pool dynamics, as previously believed. Only exclusion of evaporation in the eyewall region or the rapid filamentation zone has a very weak effect on the inner-core size change of a TC, whereas how evaporation in the outer core affects the inner-core size depends on how active the inner rainbands are. More (less) active inner rainbands may lead to an increase (a decrease) in the inner-core size.

The origin of groundwater composition in the Pampeano Aquifer underlying the Del Azul Creek basin, Argentina

The Pampean plain is the most productive region in Argentina. The Pampeano Aquifer beneath the Pampean plain is used mostly for drinking water. The study area is the sector of the Pampeano Aquifer underlying the Del Azul Creek basin, in Buenos Aires province. The main objective is to characterize the chemical and isotopic compositions of groundwater and their origin on a regional scale. The methodology used involved the identification and characterization of potential sources of solutes, the study of rain water and groundwater chemical and isotopic characteristics to deduce processes, the development of a hydrogeochemical conceptual model, and its validation by hydrogeochemical modelling with PHREEQC. Groundwater samples come mostly from a two-depth monitoring network of the “Dr. Eduardo J. Usunoff” Large Plains Hydrology Institute (IHLLA). Groundwater salinity increases from SW to NE, where groundwater is saline. In the upper basin groundwater is of the HCO3-Ca type, in the middle basin it is HCO3-Na, and in the lower basin it is ClSO4–NaCa and Cl–Na. The main processes incorporating solutes to groundwater during recharge in the upper basin are rain water evaporation, dissolution of CO2, calcite, dolomite, silica, and anorthite; cationic exchange with Na release and Ca and Mg uptake, and clay precipitation. The main processes modifying groundwater chemistry along horizontal flow at 30m depth from the upper to the lower basin are cationic exchange, dissolution of silica and anorthite, and clay precipitation. The origin of salinity in the middle and lower basin is secular evaporation in a naturally endorheic area. In the upper and middle basins there is agricultural pollution. In the lower basin the main pollution source is human liquid and solid wastes. Vertical infiltration through the boreholes annular space during the yearly flooding stages is probably the pollution mechanism of the samples at 30m depth.

ハギア・ソフィア大聖堂の壁体の雨水の浸透が壁画の劣化に与える影響

Hagia Sophia in Istanbul has been suffering from severe degradation of the outside and inside walls and the paintings on the inside wall surfaces mainly due to liquid water transport and salt crystallization. In order to elucidate the degradation mechanism and then propose a suitable method for preservation, we have conducted a long-term field survey of Hagia Sophia from 2010 until 2014 and numerical analyses of simultaneous heat and moisture transfer in the walls. It was found that high moisture content — primarily due to penetration and evaporation of rain water and partly due to consequent salt crystallization — generally leads to degradation of both inside and outside walls. It was observed that the moisture content of the north inside wall is higher than that of the south inside wall due to less solar radiation. Also, there are high possibilities that evaporation mainly at the middle-layer mortar caused salt crystallization and exfoliation of the inside stucco wall surfaces and that the exfoliation of the inside finishing material of the wall caused further subsequent exfoliation of the inner layers.

An assessment of water resources in Sinai Peninsula, using conventional and isotopic techniques, Egypt

This paper aims to reveal and to assess the groundwater availability of major multi-layered aquifer systems in Sinai. Eight major aquifer systems were identified in Sinai. These major aquifer systems spread under large areas of Sinai (61,000 km2). Isotopic characteristics for each aquifer system were expressed in terms of Oxygen-18(δ18O), deuterium (δ2H) as well as the characteristics of deuterium excess (d-excess). The hydrologic difference is reflected by d-excess instead of δ18O. The low 'd-excess' values (≤ 10) as 6‰ for quaternary aquifer and 8.6‰ for Nubian sandstones aquifer suggest that there is significant evaporation of rainwater leaving the residual groundwater with lower values of 'd-excess'. High d-excess values (> 10‰) are largely from the Jurassic and Eocene aquifers with 12‰ for Jurassic and from 9 to 11‰ for Eocene aquifers respectively. Isotopic data have reflected different slopes and different constants expressing the non-homogeneity in the isotopic composition of rainwater recharging the aquifers of Sinai, due to the presence of different air masses.