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Seasonal and spatial variation of the vertical gradient of rainfall rate was investigated using global precipitation data observed by the Precipitation Radar (PR) on the Tropical Rainfall Measuring Mission (TRMM) satellite. The vertical gradient was rendered by features of downward decreasing (DD) or downward increasing (DI) rainfall rate in the lower part of the profile. The DD profiles dominated tropical interior landmasses such as Africa and the Brazilian Plateau in summer. The DI profiles were observed over land in winter and over ocean except for regions with very little rainfall. In addition, DI profiles appeared during the height of the wet season even over the tropical landmasses, such as the mature monsoon period over inland India and over the Amazon River basin. Individual precipitation systems were also investigated in terms of their areally averaged DD and DI characteristics mainly over India. Deep (shallow) profiles tended to be DD (DI) for all seasons except the premonsoon season. As the rain area increased, the vertical gradient of rainfall rate decreased (DD tendency). Embedded in the dominant DD signature for deep storms, deep but significant DI profiles were observed in every month. They characterized the precipitation in the premonsoon season. More than half of the mesoscale/ synoptic-scale systems (rain areas >104 km2) having the significant DD or DI regions had both of them as part of their slant cores. The vertical gradients for these systems had a similar trend for both their stratiform and convective parts. During the mature period of the southwest monsoon, the number of small systems that were DI and widespread systems with moderate vertical gradient increased. [ABSTRACT FROM AUTHOR]

Six plots (three as controls) were established in southern Brazil to assess the reduction in runoff by vertical mulching (vm). In the other three, ditches (0.08-m wide, 0.4-m deep) were cut perpendicular to the slope, 2-m and 12-m upslope from the bottom of the plot where a flume was installed to measure runoff. Three simulated rainfalls (80 mm h−1 for 120 min, 80 mm h−1 for 65 min, 97 mm h−1 for 65 min) were applied with a sprinkler system to generate runoff. Compared to the controls, vm delayed its beginning by 10 to 20 min and reduced its volume by 34 to 39%, because initially all and later some runoff was caught in the ditches from where it infiltrated into the surrounding soil. Based on the experimental results, we derived a method to compute the runoff reduction by vm as influenced by ditch spacing (ds), initial soil moisture content (θi), and rainfall rate and duration. Computations for a combination of four ds (5 to 20 m), five θi (16 to 32%-vol), and three rainfall regimes (124 mm h−1 for 20 min, 66 mm h−1 for 60 min, and 42 mm h−1 for 120 min) showed an increasing runoff reduction as ds or θi decreased. In some cases, runoff was even completely prevented. The reductions were larger in the 60-min than in the 20-min rainfall. For the 120-min rainfall, there was no runoff with any combination of ds and θi. [ABSTRACT FROM AUTHOR]

During the 2010-2011 wet season in Brazil, widespread landslides triggered by heavy rainfall killed hundreds of people and displaced nearly 35,000. The extreme precipitation was associated with the formation of the South Atlantic convergence zone (SACZ). Even though the physical mechanisms behind the formation and persistence of subtropical convergence zones are still unclear, we demonstrate that early predictions of heavy rainfall in the SACZ region are possible. Precipitation rate hindcasts from the NCEP Climate Forecast System version 2 are calibrated with the aid of a gridded precipitation dataset. When the calibration was applied to the 2010-2011 events, the hindcasts were able to depict both active and break phases of the SACZ with up to 2 weeks in advance during a period of relatively weak intraseasonal variability associated with the Madden-Julian Oscillation (MJO). [ABSTRACT FROM AUTHOR]

Caatinga is a typical Brazilian biome facing severe threats despite its ecological and socio-economic importance. Conservation strategies are essential in protecting ecosystems and ensuring natural resource sustainability. Mata da Pimenteira State Park (PEMP), launched in 2012, is an example of such a strategy. The current study aims to use orbital remote sensing techniques to assess human impacts on changes in land use and land cover (LULC) after the establishment of PEMP in the semi-arid region known as Caatinga, in Pernambuco State. The effects of this unit on vegetation preservation were specifically analyzed based on using data from the MapBiomas Brasil project to assess trends in LULC, both in and around PEMP, from 2002 to 2020. Man–Kendall and Pettitt statistical tests were applied to identify significant changes, such as converting forest areas into pastures and agricultural plantations. Trends of the loss and gain of LULC were observed over the years, such as forest areas' conversion into pasture and vice versa, mainly before and after PEMP implementation. These findings highlight the importance of developing conservation measures and planning to help protecting the Caatinga, which is a vital biome in Brazil. [ABSTRACT FROM AUTHOR]

In addressing the challenges of quantitative precipitation estimation (QPE) using weather radar, the importance of enhancing the rainfall estimates for applications such as flash flood forecasting and hydropower generation management is recognized. This study employed dual-polarization weather radar data to refine the traditional Z–R relationship, which often needs higher accuracy in areas with complex meteorological phenomena. Utilizing tree-based machine learning algorithms, such as random forest and gradient boosting, this research analyzed polarimetric variables to capture the intricate patterns within the Z–R relationship. The results highlight machine learning's potential to improve the precision of precipitation estimation, especially under challenging weather conditions. Integrating meteorological insights with advanced machine learning techniques is a remarkable achievement toward a more precise and adaptable precipitation estimation method. [ABSTRACT FROM AUTHOR]

Recife Metropolitan Region (RMR, NE Brazil) lies over a multi-layered aquifer system located in an estuarial area. The region has experienced fast population growth and repeated droughts in the last three decades, which led to unprecedented anthropogenic pressure on groundwater resources because of intense water pumping. Accordingly, scientific and stakeholder communities have been challenged to ensure the maintenance of sustainable groundwater resource by managing all water cycle. Because controlling pumping rates is difficult due to the large number of illegal wells, the Managed Aquifer Recharge (MAR) strategies are now under consideration. The RMR presents a tropical climate and an annual average rainfall rate of approximately 2450 mm year −1 , providing great potential volumes of water to be used for piezometric level recovery. However, MAR implementation requires a detailed and in-depth knowledge of the human-impact on the hydrogeological behavior of the resource over the long-term, in order to find out the most appropriate recharge strategy. Therefore, the present study illustrates how routine data monitoring, i.e., piezometric level and electrical conductivity (EC), in combination with the geological knowledge, may allow proposing further MAR strategies. Two contrasted behaviors were observed in RMR: (i) groundwater level decrease and stable EC in the North and Southernmost areas of Recife; and (ii) stable groundwater level and high/varying EC values next to the estuarial zone. Although aquifers are undergoing over-abstraction, this spatiotemporal heterogeneity suggests that a recharge is possibly locally favored next to the estuarial area of the RMR thanks to hydraulic connections between surface and deep aquifers throughout extended paleo-channels. Thus, based on this typology, MAR implementation through controlled infiltration close to the estuarial area seems to be more appropriated, whereas the direct deep injection appears to be more relevant in more distant zones. [ABSTRACT FROM AUTHOR]

Currently, Brazil is the leading producer of sugarcane in the world, with self-sufficiency in the use of ethanol as a biofuel, as well as being one of the largest suppliers of sugar to the world. This study aimed to develop a predictive model for sugarcane production based on data extracted from aerial imagery obtained from drones or satellites, allowing the precise tracking of plant development in the field. A model based on a semiparametric approach associated with the inverse Gaussian distribution applied to vegetation indices (VIs), such as the Normalized Difference Vegetation Index (NDVI) and Visible Atmospherically Resistant Index (VARI), was developed with data from drone images obtained from two field experiments with randomized replications and four sugarcane varieties. These experiments were performed under conditions identical to those applied by sugarcane farmers. Further, the model validation was carried out by scaling up the analyses with data extracted from Sentinel-2 images of several commercial sugarcane fields. Very often, in countries such as Brazil, sugarcane crops occupy extensive areas. Consequently, the development of tools capable of being operated remotely automatically benefits the management of this crop in the field by avoiding laborious and time-consuming sampling and by promoting the reduction of operation costs. The results of the model application in both sources of data, i.e., data from field experiments as well as the data from commercial fields, showed a suitable level of overlap between the data of predicted yield using VIs generated from drone and satellite images with the data of verified yield obtained by measuring the production of experiments and commercial fields, indicating that the model is reliable for forecasting productivity months before the harvest time. [ABSTRACT FROM AUTHOR]

In southeast Brazil, heavy precipitation events during the summer trigger floods. These disasters are responsible for most loss of lives. In November and December 2021, the northern area of Minas Gerais and the southern part of Bahia were affected by periods of very heavy rain and intense floods. Heavy precipitation contributed to unusually high soil saturation that favored floods that claimed lives. Estimated losses totaled about $3.1 billion U.S. dollars from November to December 2021. Therefore, this study: 1. evaluates the meteorological conditions in November–December 2021, in particular from December 22 to 29, when it rained up to 300 mm above average in this region, 2. analyzes the floods, exacerbated by extreme rainfall events earlier in November and December, and 3. discusses monitoring and issuing risk alerts of these disasters by government agencies that helped minimize damage and property loss and reduce fatalities. [ABSTRACT FROM AUTHOR]

The present study focuses on the Tamoios aquifer (Rio de Janeiro State, Brazil), which is under pressure due to receiving a significant volume of urban runoff and sewage. The objective was based on a number of hydrogeochemical and isotope data to assess the aquifer functioning and establishing a conceptual model to evaluate the hydrogeochemical processes. The database consisted of groundwater samples (n = 20) and surface water samples (fluvial, lagoon, and seawater) (n = 4), analyzed for major and trace constituents plus 18O and 2H isotopes. Results demonstrate that most of the groundwater samples were classified as sodium-chloride type in the rainy season and magnesium-chloride type in the dry season. Ion ratios indicated the ion sources and chemical behavior. Groundwater remained with a relatively high salt content throughout the seasons, particularly in the samples from the southern portion of the aquifer. PHREEQC software simulations exposed dolomite and calcite in mostly undersaturated condition and halite subsaturated throughout the year. Hydrogeochemical behavior indicated the salt content in the groundwater was not related to a hypothetical saltwater intrusion and revealed a steady state condition for the groundwater interface. Groundwater samples have a similar isotopic signature and were likely influenced by evaporative effects, indicating a role for the existing ponds in aquifer recharge. Strong free surface evaporation effects, evapotranspiration, and drainage processes in the floodplains probably enhanced the high ionic concentration in the groundwater environment. [ABSTRACT FROM AUTHOR]

Bokermannohyla hylax is an endemic tree frog from the Atlantic Forest and despite being a common species, very little is known about its population traits and reproduction. We undertook acoustic and visual encounter surveys, and individual marking studies of a subpopulation in an urban forest fragment, the Parque Estadual das Fontes do Ipiranga, located in the São Paulo municipality. We detected a small population that breeds in only one forest stream, and deposits eggs inside burrows along the stream's clayey border. Our findings also suggest that this subpopulation might be vulnerable due to the specific characteristics of its reproduction, which may be affected by the degree of disturbance of this fragment. [ABSTRACT FROM AUTHOR]

Copyright of Acta Veterinaria Brasilica is the property of Acta Veterinaria Brasilica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Global Positioning System (GPS) consists of a constellation of satellites that transmit radio frequency signals to many users with varied applications. For meteorological purposes, the based-ground GPS receivers can provide high-quality column or precipitable water vapor (PWV), as obtained by radiosondes, but with high temporal resolution and low cost. A dense GPS network containing 16 ground-based receivers was installed in Belém city, Brazil, during the period 2–29 June 2011. This network provides a unique opportunity to evaluate the sensitivityof rapid increases in GPS PWV (GPS PWV jumps to the intense precipitation often associated with tropical organized convective systems. Results reveal a characteristic timescale of water vapor convergence before GPS-PWV maximum, which can be used for indicating the occurrence of precipitation associated with organized convective systems. A PWV increase of 4 mm h − 1 in a period of an hour or 30 min before the maximum peak GPS-PWV (a peak of at least 57 mm) was observed during organized convection events. The contingency table obtained indicates a probability of detection of 84% and a false alarm ratio of 25% to forecast precipitation events. These results obtained suggest that GPS-PWV jumps can be employed to predict the events associated with organized convection. [ABSTRACT FROM AUTHOR]

Observations from geostationary satellites can provide spatially continuous coverage at continental scales with high spatial and temporal resolution. Because of this, they are commonly used to complement ground-based precipitation measurements, whose coverage is often more limited. We present Hydronn, a neural-network-based, near-real-time precipitation retrieval for Brazil based on visible and infrared (Vis–IR) observations from the Advanced Baseline Imager (ABI) on the Geostationary Operational Environmental Satellite 16 (GOES-16). The retrieval, which employs a convolutional neural network to perform Bayesian precipitation retrievals, was developed with the aims of (1) leveraging the full potential of latest-generation geostationary observations and (2) providing probabilistic precipitation estimates with well-calibrated uncertainties. The retrieval is trained using more than 3 years of collocations with combined radar and radiometer retrievals from the Global Precipitation Measurement (GPM) core observatory over South America. The accuracy of instantaneous precipitation estimates is assessed using a separate year of GPM combined retrievals and compared to retrievals from passive microwave (PMW) sensors and HYDRO, the Vis–IR retrieval that is currently in operational use at the Brazilian Institute for Space Research. Using all available channels of the ABI, Hydronn achieves accuracy close to that of state-of-the-art PMW precipitation retrievals in both precipitation estimation and detection despite the lower information content of the Vis–IR observations. Hourly, daily, and monthly precipitation accumulations are evaluated against gauge measurements for June and December 2020 and compared to HYDRO, the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN) Cloud Classification System (CCS), and the Integrated Multi-satellitE Retrievals for GPM (IMERG). Compared to HYDRO, Hydronn reduces the mean absolute error for hourly accumulations by 21 % (22 %) compared to HYDRO by 44 % (41 %) for the mean squared error (MSE) and increases the correlation by 138 % (312 %) for June (December) 2020. Compared to IMERG, the improvements correspond to 16 % (14 %), 12 % (12 %), and 20 % (56 %), respectively. Furthermore, we show that the probabilistic retrieval is well calibrated against gauge measurements when differences in the distributions of the training data and the gauge measurements are accounted for. Hydronn has the potential to significantly improve near-real-time precipitation retrievals over Brazil. Furthermore, our results show that precipitation retrievals based on convolutional neural networks (CNNs) that leverage the full range of available observations from latest-generation geostationary satellites can provide instantaneous precipitation estimates with accuracy close to that of state-of-the-art PMW retrievals. The high temporal resolution of the geostationary observation allows Hydronn to provide more accurate precipitation accumulations than any of the tested conventional precipitation retrievals. Hydronn thus clearly shows the potential of deep-learning-based precipitation retrievals to improve precipitation estimates from currently available satellite imagery. [ABSTRACT FROM AUTHOR]

Pollution from sewage discharge is one of the most critical environmental problems worldwide, e.g., in Brazil, where basic sanitation is still scarce. As pollution can affect biomes, especially estuaries where intensive ecological and human activities occur, has caused widespread concern. This work aimed to study the water quality of the Jundiaí/Potengi Estuary (JPE) in an area close to the discharge of treated and untreated wastewater for 18 months. Physicochemical and microbiological parameters were measured and integrated using the Water Quality Index of the Canadian Council of Ministers of the Environment. Ecotoxicological tests were performed with Brazilian endemic organisms to assess the impact of water pollution on biota. A generalized linear regression model was applied to understand the effects of water quality on ecotoxicological responses. Concentrations of metals, dissolved oxygen, total ammonia nitrogen, nitrate, and thermotolerant coliforms did not comply with Brazilian environmental regulations. A significant increase in the mortality rate of Mysidopsis juniae and Nitocra sp. and a significant decrease in the reproductive rate of Nitocra sp. indicated the most affected areas related to the discharge of treated and untreated wastewater. Only 10% of the samples from sites without direct wastewater impact showed a toxic response in at least one organism. Both water quality and sampling sites were statistical predictors of ecotoxicological response, describing not only the pollutant load but also the type of effluent. This study demonstrated the degradation of the environmental quality of the JPE, particularly due to the discharge of sanitary wastewater, and highlights the importance of protection and remediation measures to preserve this protected area. [ABSTRACT FROM AUTHOR]

This paper presents a comparison between rain gauge network and weather radar data in Angra dos Reis city, located in the State of Rio de Janeiro (RJ), Brazil. The city has a high incidence of natural disasters, especially associated with heavy rains in densely populated areas. In this work, weather radar data with a spatial resolution of 1 km were obtained from dual-polarimetric S-band radar operated by the Environmental State Institute of Rio de Janeiro (INEA), located in the Guaratiba neighborhood in Rio de Janeiro city, Brazil; the rain gauge measurements were provided by the National Center for Monitoring and Warning of Natural Disasters (CEMADEN), which is composed of a network with 30 rain gauges covering the studied area. The comparison between the two datasets enables the analysis of which radar products better fit the rain gauge network's accumulated rainfall by quantifying the uncertainties in precipitation estimates at radar pixels where rain gauges are located. The results indicated that radar products generated with the help of regression techniques obtained from the relation between radar reflectivities and rain gauge measurements were a better fit, constituting essential information while dealing with efficient regulation for rainfall monitoring and forecasting to minimize the risks associated with extreme events. [ABSTRACT FROM AUTHOR]

Studies have shown that deforestation can cause changes in energy, moisture, and precipitation flows, with implications for local and regional climate. These studies generally focus on understanding how the hydrological cycle is impacted by deforestation, but few studies have investigated these impacts on cloud microphysics in tropical forest regions. The objective of this study was to quantitatively evaluate the impacts of deforestation on the microphysical parameters of clouds, based on data extracted from active and passive orbital sensors from the TRMM satellite. The study area comprised the state of Rondônia, Brazil. The analyses of the microphysical parameters extracted from the Microwave Imager (TMI) and Precipitation Radar (PR) sensors of the 2A-CLIM and 2A25 products were performed considering a period of 14 years. The parameters analyzed were Rain Water Path (RWP), Ice Water Path (IWP), Surface Precipitation (SP), Freezing Level Height (FH), and Rainfall Type (RT). Land cover type data were extracted from the Project to Monitor Deforestation in the Legal Amazon (PMDA). Our results showed that local deforestation significantly altered the microphysical parameters of the study region. In general, the values of the microphysical parameters of the clouds in the transition areas (locations where forest pixels are neighbors to deforested pixels) were about 5–25% higher compared to forested and deforested areas associated with a higher frequency of episodes of convective rainfall possibly driven by mesoscale circulations. Correspondingly, forested areas had higher rainfall rates compared to deforested areas. Meanwhile, deforested areas had higher amounts for IWP, of around 1–16%, and FH, of around 2–8%, in relation to forested areas. Conversely, the RWP showed a decrease of around 2–20%. These results suggest that the microphysical structure of clouds has different characteristics when related to forested and deforested areas in the Amazon. This is useful for evaluation of simulations of cloud microphysical parameters in numerical models of weather and climate. [ABSTRACT FROM AUTHOR]

Brazil has been leading the consumer market for pesticides, mainly due to greater flexibility in registration for agricultural use. The constant application of chemicals increases the likelihood of contaminating adjacent aquatic environments. Furthermore, fluctuations in abiotic variables, especially in subtropical countries, can enhance the effects of pesticides on the aquatic community. The aims of the current study are to investigate the incidence of pesticides in a river in southern Brazil and to evaluate the water quality and toxicity biomarkers on fish species Astyanax jacuhiensis (Cope, 1894), in different crop seasons. Water, sediment, and fish samples were collected in the summer, autumn, and winter of 2019. The herbicides atrazine and clomazone and insecticide imidacloprid were identified in water throughout the sampling period—only atrazine has the maximum concentration established for surface water by Brazilian legislation. Redundancy analysis (RDA) mainly showed the effects of seasonality on biochemical responses such as pH and water temperature. Also, most A. jacuhiensis biomarkers alterations were associated with winter and autumn periods. Furthermore, it was possible to verify the relationship between non-enzymatic antioxidants (non-protein thiols) and oxidative damage (lipid peroxidation and protein carbonylation). Therefore, the results of pesticides detected in water emphasize the need to update Brazilian legislation for compounds registered in the country. Changes in the physicochemical variables of water can influence the responses of biomarkers in addition to pesticides. Finally, biomonitoring studies are important and necessary mainly in subtropical regions where there is variation in climatic conditions between periods of the year. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The number of natural disasters triggered by extreme events is increasing worldwide and significantly impacts modern society. Extreme rainfall is one of the most important factors contributing to these events. A better understanding of the physical process that causes extreme rainfall can allow rapid responses from decision-makers to lessen the impact of natural disasters on the local population. Satellite monitoring is widely used for this purpose and is essential for regions where terrestrial observations are limited or non-existent. The primary purpose of this study is to describe the performance of satellite products for extreme rainfall events that caused natural disasters in various climate regimes in Brazil and discuss the contribution of mesoscale convective systems (MCS) to these events. We defined regions based on the climatological rainfall distribution. Cases with rain values above the 99th percentile during 2012–2016 were considered statistically extreme. Our analysis is based on three datasets, with precipitation from (i) rain gauge stations, (ii) different satellite-based estimates, and (iii) mesoscale convective tracking data. The methodology was based on identifying extreme rainfall events, analyzing the performance of satellite precipitation estimates and, finally, quantifying the influence of convective systems on extreme rain. Although all regions of Brazil may be affected by natural disasters caused by extreme rains, the results suggest that the impacts caused in each region are different in magnitude. Convective systems explained over 90% of extreme rains in the case analyzed in Brazil's south and about 60% to 90% of extreme rains in the case analyzed in the Northeast. In general, satellite products have identified rain events; however, in the southern region of Brazil, products have tended to overestimate rainfall, while other regions have tended to underestimate extreme rain values. The methods used in satellite precipitation estimation products have limitations to accurately identifying specific extreme rain events. [ABSTRACT FROM AUTHOR]

A 3‐year study on erosion and streamflow was conducted in two adjacent paired watersheds that flow into the Passo Real reservoir, one of the largest and most important reservoirs for human water supply and power generation in southern Brazil. The watersheds have similar land use and soil management, but different size and riparian vegetation. The first objective of the study was to monitor and evaluate hydrosedimentological dynamics and effects of riparian vegetation, over a range of rain events, in the two watersheds; the second was to assess the ability of the Limburg Soil Erosion Model (LISEM) to represent these small watersheds in hydrosedimentological terms (runoff and erosion) under individual rain events, in the context of better understanding the role of riparian vegetation and land cover. LISEM is a hydrological model structured on physically based equations that can be used for planning and conservation purposes. Studied rainfall events between 2016 and 2018 had a wide range in total rainfall (10–170 mm), rainfall intensity in 1 h (3–66 mm h−1), stream peak flows (4–5741 L s−1), runoff volume (0.02–40 mm), runoff coefficient (0.1–32%), maximum suspended sediment concentration (20–19 611 mg L−1), and sediment yield (0.002–33.790 Mg km−2). Both watersheds showed a rapid response to rain events with significant runoff generation. Abundance of unpaved roads (often parallel to the slope) promoted high runoff due to channelization effects. South Watershed has 59% more riparian vegetation than North Watershed, but this greater riparian vegetation was not effective in reducing surface runoff and erosion. Furthermore, local adoption of no‐tillage was insufficient to control runoff and sediment yield. [ABSTRACT FROM AUTHOR]

Tourist occupancy in coastal environments threatens the stability of various coastal ecosystems and is thus a cause for concern for the environmental sector. As such, it is important to perform environmental monitoring in a way that analyses and quantifies the environmental impact of coastal ecosystems. Porto de Galinhas beach (Pernambuco – Brazil) has one of the highest visitation rates in Brazil and suffered from restrictions to human mobility due to the COVID-19 pandemic. These restrictions allowed for the evaluation of the impact of tourism on Porto de Galinhas beach and the effects that the lack of tourist occupancy had during the lockdown period of 2020. Blood samples from the species Abudefduf saxatilis were collected monthly over a period of 1 year and during the lockdown quarter, in order to perform micronucleus (MN) and nuclear morphological alteration (NMA) tests, and data were analyzed at a seasonal level (dry/rainy period) using a comet assay. For the control group, A. saxatilis samples were collected in an environmentally protected area on Tamandaré beach (68 km from Porto de Galinhas). The MN and NMA tests showed a greater frequency of genomic damage when there was greater tourist flow. In relation to rain seasonality, the comet assay showed a greater incidence of genomic damage during the dry period, where there was a higher rate of tourist migration, compared to the rainy period. The lockdown period presented a lower incidence of genotoxic damage compared to the period without restrictions on human mobility and the control. The results show that tourism has been causing a significant environmental impact on Porto de Galinhas beach. The data collected during the lockdown period demonstrated how the absence of human movement results in changes that are favorable to environmental recuperation, as illustrated by the lower frequency of genomic damage. [ABSTRACT FROM AUTHOR]

Abstract: This study investigates how the summer thunderstorms developed over the city of São Paulo and if the pollution might affect its development or characteristics during the austral summer (December–January–February–March, DJFM months). A total of 605days from December 1999 to March 2004 was separated as 241 thunderstorms days (TDs) and 364 non-thunderstorm days (NTDs). The analyses are performed by using hourly measurements of air temperature (T), web-bulb temperature (Tw), surface atmospheric pressure (P), wind velocity and direction, rainfall and thunder and lightning observations collected at the Meteorological Station of the University of São Paulo in conjunction with aerosol measurements obtained by AERONET (Aerosol Robotic Network), and the NCEP-DOE (National Centers for Environmental Prediction Department of Energy) reanalysis and radiosondes. The wind diurnal cycle shows that for TDs the morning flow is from the northwest rotating to the southeast after 16:00 local time (LT) and it remains from the east until the night. For the NTDs, the wind is well characterized by the sea-breeze circulation that in the morning has the wind blowing from the northeast and in the afternoon from the southeast. The TDs show that the air temperature diurnal cycle presents higher amplitude and the maximum temperature of the day is 3.2°C higher than in NTDs. Another important factor found is the difference between moisture that is higher during TDs. In terms of precipitation, the TDs represent 40% of total of days analyzed and those days are responsible for more than 60% of the total rain accumulation during the summer, for instance 50% of the TDs had more than 15.5mmday−1 while the NTDs had 4mmday−1. Moreover, the rainfall distribution shows that TDs have higher rainfall rate intensities and an afternoon precipitation maximum; while in the NTDs there isn''t a defined precipitation diurnal cycle. The wind and temperature fields from NCEP reanalysis concur with the local weather station and radiosonde observations. The NCEP composites show that TDs are controlled by synoptic circulation characterized by a pre-frontal situation, with a baroclinic zone situated at southern part of São Paulo. In terms of pollution, this study employed the AERONET data to obtain the main aerosol characteristics in the atmospheric column for both TDs and NTDs. The particle size distribution and particle volume size distribution have similar concentrations for both TDs and NTDs and present a similar fine and coarse mode mean radius. In respect to the atmospheric loading, the aerosol optical depth (AOD) at different frequencies presented closed mean values for both TDs and NTDs that were statistically significant at 95% level. The spectral dependency of those values in conjunction with the Angstrom parameter reveal the higher concentration of the fine mode particles that are more likely to be hygroscopic and from urban areas. In summary, no significant aerosol effect could be found on the development of summer thunderstorms, suggesting the strong synoptic control by the baroclinic forcing for deep convective development. [Copyright &y& Elsevier]

This research aimed to quantify and qualify alterations in land cover and verify the implications of these modifications for variables related to energy flows and water cycle in São Francisco basin (SFB), located entirely in Brazilian territory, in the second half of the twentieth century and beginning of the twenty-first. For this, statistical analyses (descriptive, trends, seasonal, and correlations) were used to quantify changes in the variables of land cover and energy/water flows, in addition to relating them. As a result, it was found that the SFB lost 65,680 km2 of native vegetation (10.4% of basin area) to crops and pastures, reducing water infiltration (− 52%), while the rains remained stable (− 2%). Water loss increased through evapotranspiration (+ 5%) and surface runoff (+ 225%). Such changes in the water cycle have entailed an 11% reduction in São Francisco river long-term flow rate (Q 95), comparing pre- and post-1990s period. In SFB, the activities that required water, such as farming activities, are those that promote hydric loss. [ABSTRACT FROM AUTHOR]

Deep convection overshooting the lowermost stratosphere is well known for its role in the local stratospheric water vapour (WV) budget. While it is seldom the case, local enhancement of WV associated with stratospheric overshoots is often published. Nevertheless, one debatable topic persists regarding the global impact of this event with respect to the temperature-driven dehydration of air parcels entering the stratosphere. As a first step, it is critical to quantify their role at a cloud-resolving scale before assessing their impact on a large scale in a climate model. It would lead to a nudging scheme for large-scale simulation of overshoots. This paper reports on the local enhancements of WV linked to stratospheric overshoots, observed during the TRO-Pico campaign conducted in March 2012 in Bauru, Brazil, using the BRAMS (Brazilian version of the Regional Atmospheric Modeling System; RAMS) mesoscale model. Since numerical simulations depend on the choice of several preferred parameters, each having its uncertainties, we vary the microphysics or the vertical resolution while simulating the overshoots. Thus, we produce a set of simulations illustrating the possible variations in representing the stratospheric overshoots. To better resolve the stratospheric hydration, we opt for simulations with the 800 m horizontal-grid-point presentation. Next, we validate these simulations against the Bauru S-band radar echo tops and the TRO-Pico balloon-borne observations of WV and particles. Two of the three simulations' setups yield results compatible with the TRO-Pico observations. From these two simulations, we determine approximately 333–2000 t of WV mass prevailing in the stratosphere due to an overshooting plume depending on the simulation setup. About 70 % of the ice mass remains between the 380 and 385 K isentropic levels. The overshooting top comprises pristine ice and snow, while aggregates only play a role just above the tropopause. Interestingly, the horizontal cross section of the overshooting top is about 450 km 2 at the 380 K isentrope, which is similar to the horizontal-grid-point resolution of a simulation that cannot compute overshoots explicitly. In a large-scale simulation, these findings could provide guidance for a nudging scheme of overshooting hydration or dehydration. [ABSTRACT FROM AUTHOR]

Copyright of Rodriguésia is the property of Revista Rodriguesia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ability to forecast extreme precipitation events has become increasingly important over the last decades due to their significant impacts on society and properties. In this context, the reliability degree related to the warnings issues and a possible natural hazard is relevant. Thus, research aimed to evaluate the strengths and weaknesses of numerical forecasts can also be addressed as prevention measures. In this context, first, this study endeavored to identify the extreme precipitation events in Macaé city, Brazil. Secondly, evaluate the precipitation forecast using the Weather Research and Forecasting (WRF) model using different lead time initialization and three grids domain (27, 09, and 03 km); and investigate the thermodynamic and dynamic physical processes related to the extreme events found. From the qualitative and quantitative evaluation of the precipitation forecast, it was possible to verify that the 24 h lead time initialization presented the best performance compared to the other ones. The third domain also presented the statistical results of the precipitation forecasts, suggesting that the increased horizontal resolution enabled the model to represent mesoscale physical processes and better use high-resolution input data, such as the mountainous region of Macaé city. It was possible to verify the importance of conditional atmospheric instability, moisture offer at lower atmospheric levels, and dynamic trigger mechanisms to originate the extreme rainfall events from the thermodynamic and dynamic parameters. Lastly, we sought to show the challenges of forecasting the extreme rainfall and natural hazards imminence warnings and exploring the daily operational challenges verified in the monitoring centers and civil defenses. [ABSTRACT FROM AUTHOR]

This study provides for the first time information about the reproductive biology of Mimagoniates lateralis, an endangered species of inseminating Neotropical tetra that occurs in blackwater streams of southeastern Brazil. We analyzed 404 individuals, of which 214 were females, 117 were males, and 73 were immature juveniles. The sex ratio was 1.83 females/males. Males were larger than females. The estimated size at first maturation for females was 22.2 mm SL, and for males 23.4 mm SL. We also analyzed 94 ovaries from mature females, and the estimated absolute fecundity was 116.37 ± 26.68 oocytes, the oocyte diameter varying from 0.1 to 1.0 mm. The spawning type was classified as multiple, with two modal values corresponding to different oocyte lots. These data contribute to substantiate future assessments of the conservation status of M. lateralis, as well as future attempts to guarantee the preservation of this species and its natural habitat. [ABSTRACT FROM AUTHOR]

The relationship between forest cover and streamflow of watersheds is complex and still controversial in the scientific literature. To investigate such relationship we propose an alternative method which requires the following information for each watershed: percentage of forest cover, annual rainfall, average specific streamflow (qave), and minimum mean specific streamflow in seven consecutive days (q7). As a case study, we analyzed a dataset composed by 25 watersheds located in the Espírito Santo State (ESS), Brazil. We conducted simple and multiple linear regression analyses as well as partial correlation analysis between the above parameters. To reduce the effect of heterogeneity of environmental factors, watersheds with similar characteristics in term of rainfall, drainage area, and both rainfall and drainage area were grouped by cluster analysis, and the above regression and correlation analysis was repeated on each group. Our results using the whole dataset showed that forest cover has a negative relationship with watershed streamflow. The analysis of homogeneous groups of watersheds showed that the average minimum streamflow during seven days (q7) was more sensitive to the presence of forest cover, showing a negative relationship, especially in watersheds with low annual rainfall, while in areas with high precipitation, the annual rainfall showed a strong influence on the hydrological responses of watersheds, masking the effect of forest cover. The proposed method may be easily extended to other areas, and allows the inclusion of other relevant environmental variables according to specific cases. [ABSTRACT FROM AUTHOR]

No‐till (NT) is a soil management system designed to protect soil resources from water erosion and provide numerous benefits compared to conventional tillage through the increase of organic matter inputs into the soil. However, NT in isolation is not sufficient to control erosion processes caused by an excessive production of surface runoff. This study evaluated soil losses on agricultural hillslopes under no‐till characterized by contrasted water, soil, and crop management conditions. To this end, water and soil losses were monitored between 2014 and 2018 at two scales, including four macroplots (0.6 ha; 27 events) and two paired zero‐order catchments (2.4 ha; 63 events). The resulting dataset covered a wide range of rainfall conditions that occurred in contrasted soil, crop, and runoff management conditions. Hyetographs, hydrographs, and sedigraphs were constructed, and these data were used to evaluate the impact of management on sediment yields, including that of terraces, scarification, and phytomass on sediment yield. The installation of terraces reduced sediment yield by 58.7%, mainly through surface runoff control. Crop management including an increased phytomass input efficiently controlled soil losses (63%), although it did not reduce runoff volume and peak flow. In contrast, scarification had no impact on runoff and soil losses. The current research demonstrated the need to combine the installation of terraces and leaving a high amount of phytomass on the soil to control surface runoff and erosion and reduce sediment yield. The current research therefore reinforces the relevance of the monitoring strategy conducted at the scale of macroplots and zero‐order catchments to evaluate the impact of contrasted water, soil, and crop management methods and select the most effective conservation agriculture practices. [ABSTRACT FROM AUTHOR]

Passion fruit woodiness disease induced by Cowpea aphid-borne mosaic virus (CABMV) is currently the most harmful viral disease affecting passion fruit crops. Given the economic importance of this fruit crop in Brazil, it is essential that passion fruit breeding programs invest in developing resistant and productive cultivars. The goals of this study were to estimate genetic parameters of agronomic and resistance traits via restricted maximum likelihood (REML) and select individuals found to be resistant to CABMV and agronomically superior, in order to provide the basis for further studies on passion fruit breeding, with the aim to develop cultivars resistant to CABMV. The study was conducted in randomized block design, with four replicates. Three full-sib families from the recombination of RC1 parents were evaluated. Based on the severity data, the area below the mean disease progress curve (AUDPCM) was estimated. Five traits relating to fruit yield and quality were also assessed. The components of variance and genetic values were estimated by the REML/best linear unbiased prediction (BLUP) mixed model methodology. A difference in the severity of CABMV symptoms was recorded among the 119 genotypes evaluated. AUDPCM values varied from 750 to 1252.5 for individuals 202 and 161, respectively. Family 1 distinguished itself with the largest number of individuals selected for resistance; for agronomic traits, families 1 and 2 contributed most of the selected genotypes. Genotypes 167, 24, 34, 23 and 202 achieved the lowest AUDPCM values, being selected for most of the agronomic traits; these results indicate the potential of these genotypes to be chosen and recombined for the advancement of generations in breeding programs aimed at developing resistance to CABMV. The strategy of recombining resistant genotypes from RC1 populations appears to be promising for breeding for resistance to CABMV, of which the heritability is complex. [ABSTRACT FROM AUTHOR]

Rural headwater catchments are important to describe the connectivity of pollution sources to water bodies. Strategies to optimize water quality monitoring networks, as parameter definition, sampling, and statistical approach, have been widely discussed. The objectives of this study were to describe the spatial and temporal dynamics (intra- and inter-events) of water quality and to establish its implications for environmental monitoring programs. The monitoring was carried out in a rural headwater catchment (1.2 km2) with shallow soils, high slopes, and intense agricultural activity in Southern Brazil. To better describe the impact of agriculture on water resources, the monitoring strategy was based on definition of the best set of parameters and different sampling frequency to incorporate intra- and inter-event variability and statistical analysis approach. We also analyzed parameters in different sub-basins with physiographic traits. Three hydrological compartments were analyzed: surface flow, groundwater, and base flow. Physico-chemical parameters, the concentration of elements associated with agricultural activity, and biological parameters were evaluated. Total phosphorus and turbidity were the parameters most affected by agricultural activity. They reflected on the inter- and intra-events, the impacts of soil and water degradation by agricultural activity, and the precarious rural sanitation conditions. Spatiotemporal variability of the parameters characterizes the different mechanisms for transferring pollutants from diffuse sources to water bodies. Spatial and temporal patterns in water quality changes were used to discuss environmental monitoring strategies, such as parameter and sampling frequency definition, to improve soil and water conservation programs at the catchment scale. [ABSTRACT FROM AUTHOR]

There is little information about the availability of water in the Cerrado biome, the main agricultural frontier in Brazil, especially about groundwater, and this has compromised the region's economic and social development, as well as environmental sustainability. The reduction of rainfall in this region, indicated by numerous climate models, may reduce aquifer recharge and, consequently, groundwater availability and sustainable development of the Cerrado biome. This study aimed to evaluate the impact of global climate change on groundwater recharge in a Brazilian Savannah watershed. Rainfall and water table depth data were recorded between 2007 and 2015. Based on these data, equations were developed relating the average monthly depth of the water table with the accumulated average monthly rainfall. From these equations, monthly average recharges considering the future climate estimates made by climate models (Eta-HadGEM2-ES and Eta-MIROC5) and Representative Concentration Pathway (RCP) scenarios (4.5 and 8.5) were calculated. In a pessimistic scenario (RCP 8.5), the average monthly groundwater recharge is decreasing in the beginning and in the end of the rainy season, indicating that there may be an increase in the dry season and, consequently, a reduction in water availability in the Cerrado biome region. [ABSTRACT FROM AUTHOR]

Agribusiness is one of the main economic activities in Brazil, which caused the removal of much of its natural vegetation for the expansion of monoculture areas. Once aquatic environments have a direct relationship with the surrounding terrestrial environment, it is essential to understand the monocultures' impact on adjacent streams and, especially, how aquatic communities react to these impacts. Our aim was to verify the effects of different monoculture types on stream benthic macroinvertebrate and fish communities' structure. We compared the environmental characteristics and these communities' structure in four streams located in native vegetation areas and four in each of three monoculture types (sugarcane, citrus, and eucalyptus), all belonging to the Paranapanema River basin, Southeastern Brazil. We found lower pH and dissolved oxygen and higher total phosphorus and fine substrate values in monoculture streams and these variables were also related to the lower abundance of macroinvertebrate groups more sensitive to environmental impacts. However, we did not find differences in fish communities or in their relationship with the different environmental characteristics observed. We also did not observe differences between the monoculture types in all comparisons made, which demonstrate that these plantations, although have different cultivation characteristics, cause similar negative impacts in the streams. Our study demonstrates the physical and chemical impacts of monoculture development on stream headwater communities. Regulatory measures such as increased riparian vegetation and contour farming and terracing may be critical to protect and restore headwater streams from monoculture impacts. [ABSTRACT FROM AUTHOR]

Copyright of Floresta is the property of Revista Floresta and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Real-time rainfall distribution is required for decision-making based on the support of warning systems, especially in situations of imminent floodings and landslides. In this work, six relationships on radar reflectivity–rainfall relationships were calibrated and evaluated for 33 rainfall events associated with Quitandinha River flooding with occurred between 2013 and 2016. These events were chosen with the purpose of finding new relationships that could characterize with better accuracy the properties of storms and precipitation associated with Quitandinha floods. The procedure of applying variations of 5%, 10%, and 20% in reflectivity band-pass filter was used to minimize the different types of uncertainties associated with the measurement of radar reflectivity and rain gauges. Multiple linear regression analysis approach showed that radar reflectivity–rainfall relationships which were calibrated at 20% presented the lowest dimensionless coefficient of variability (CV), systematic error (BIAS), mean absolute deviation MAD), and root-mean-square error (RMSE). The calibrated expression between Marshall–Palmer and Nexrad showed the best performance among the six relationships examined. [ABSTRACT FROM AUTHOR]

This paper presents a study of diurnal tidal winds observed simultaneously by two meteor radars located on each side of the Equator in the equatorial region. The radars were located in Santa Cruz, Costa Rica (10.3 ∘ N, 85.6 ∘ W) (hereafter CR) and São João do Cariri, Brazil (7.4 ∘ S, 36.5 ∘ W) (hereafter CA). The distance between the sites is 5800 km. Harmonic analysis has been used to obtain amplitudes and phases (hour of peak amplitude) for diurnal, semidiurnal and terdiurnal tides between 82 and 98 km altitude, but in this work we concentrate on the diurnal component. The period of observation was from April 2005 to January 2006. The results were compared to the Global Scale Waves Model (GSWM-09). Magnitudes of zonal and meridional amplitudes from November to January for CR were quite different from the predictions of the model. Concerning phases, the agreement between model and radar meridional tidal phases at each site was good, and a vertical wavelength of 24 km for the diurnal tide was observed practically every month, although on some occasions determination of the vertical wavelength was difficult, especially for the zonal component, due to nonlinear phase variations with height. For the diurnal zonal amplitude, there were notable differences between the two sites. We attribute this site-to-site difference of the diurnal zonal amplitude to the nonmigrating component of the tide and propose that an anomaly was present in the troposphere in the winter (Northern Hemisphere) of 2005–2006 which produced substantial longitudinal variation. [ABSTRACT FROM AUTHOR]

Copyright of Sustainability in Debate / Sustentabilidade em Debate is the property of University of Brasilia, Center for Sustainable Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Heavy rainfall events can result in natural disasters and cause innumerous impacts on society. These consequences can be mitigated by preventive measures applications which are interdisciplinary and integrated areas of study. From the meteorological point of view, preventive measures can be aided by better knowledge of extreme phenomena, the atmospheric patterns related and their monitoring by operational forecasters. The Petropolis city, located in a mountainous region Rio de Janeiro state, Brazil, is prone to heavy rainfall events, leading to the River flooding, and in the extreme events the simultaneously landslides occurrence and loss of life. In that context, this study endeavored to characterize the rainfall and atmospheric parameters which triggered heavy rainfall records and the corresponding Quitandinha River flooding episodes. More specifically, we analyzed events from the time period between January 2013 and December 2014 using observational, reanalysis and radar data. We hope that the overall obtained results could provide quantitative and qualitative aid to the operational forecasters and also the decision makers. We noticed that categorized flooding events mostly related to the South Atlantic Convergence Zone (SACZ) configurations and frontal systems (FS) passage, with a smaller percentage related to local convective storms (CS). The clustering analyses indicated three groups of homogenous precipitation, with higher values over the downstream region progressively decreasing in the upstream direction. The atmospheric parameters showed a pattern of wind change direction in the lower atmospheric levels, a vertical dynamic coupling and moisture availability to support the heavy rainfall development. [ABSTRACT FROM AUTHOR]

Given the lack of studies about dry spells over Southeastern Brazil (SEB), the present study aims to characterize them considering their duration, geographical incidence, and association with rainfall. Uninterrupted sequences of no‐rain days were calculated using the high‐resolution (10 km) Multi‐Source Weighted‐Ensemble Precipitation data set (MSWEP; 1979–2016). The majority of dry spells (80%) last no more than 9 days and those remaining for 10 days or more are relatively rare (top 20%). January and February present a predisposition for the occurrence of dry spells, feature that is not observed in December. The life cycle of dry spells evolves in close association with the subseasonal rainfall tendency. When adding the perspective of dry spells, the effective peak of the monsoon season is December, the month with the highest rainfall rates and the lowest chances for dry spells. Afterward, dry spells modulate a progressive weakening of the rainy season until March, when a slight recovery may happen in the central northern portions of SEB. The relationship between dry spells and rainfall is not straightforward. For dry spells that are most common (up to 9 days), the most likely association is with negative monthly anomalies up to −1.0 SD. However, there are also significant chances of having dry spells associated with positive anomalies. Extreme long dry spells, but extremely rare as well, are unequivocally associated with negative anomalies. The geographic discrimination of dry spells evidences a dipole‐like feature, better seen in January and February, similar to the well‐known rainfall dipole. The north and northeast portions tend to be drier, more prone to the occurrence of dry spells, both short/frequent and long/infrequent. In the south and southwestern portions, dry spells tend to be shorter. The main result is the indication of a probable lessening in the rainy season, taking place between January and February that might affect a significant portion of SEB. [ABSTRACT FROM AUTHOR]

This paper presents a numerical method for considering soil-atmosphere interaction applied to infiltration into an unsaturated geosynthetic reinforced soil wall and its effect on wall stability. A hypothetical nonwoven geotextile reinforced soil wall was subjected to simulated conditions of evaporation and precipitation over 2 years considering local climate variation in São Paulo city, Brazil. Net infiltration and actual evaporation were quantified inside and outside the reinforced zone, allowing for the assessment of changes in soil suction and factors of safety. The study discusses the implications of using in-plane draining reinforcements (e.g. nonwoven geotextiles) and soil-atmosphere effects. Results show that soil suction and factors of safety variation are more dependent on consecutive days of precipitation than on isolated heavy rainfalls. For the climate conditions considered in this study, results show that approximately 50% of the precipitation and potential evaporation transformed into net infiltration and actual evaporation, respectively. Additionally, the numerical results indicate that after the first wetting of the soil inside the reinforced soil zone, the evaporation to the atmosphere did not remove water from the inside of the geosynthetic reinforced wall because of the capillary break. [ABSTRACT FROM AUTHOR]

Soil is the support medium for the development of several activities; however, improperly used soils can become a serious environmental issue. The aim of the current study is to determine the concentration of chemical elements in soil used as landfill in Southern Brazil. Samples were collected in different soil profiles and depths and analyzed based on the X-ray fluorescence technique. Results have indicated changes in cadmium and chromium concentrations, regardless of the collection depth. The presence of iron oxides/hydroxides and 1:1 low CEC kaolinite clay in the samples may have contributed to the translocation of these elements to the underground environment. Thus, the adopted technique was efficient and enabled identifying changes in the concentrations of the investigated elements, which can be associated with their translocation through soil profile (in depth), as well as in comparing such concentrations to the ones set by the current legislation. [ABSTRACT FROM AUTHOR]

A large-scale survey of natural radionuclides in the soils is presented. 105 topsoil samples were collected and analysed by gamma spectrometry. The data indicated that climatic conditions might impact the content of natural radionuclides. Low-humidity conditions and igneous bedrock were associated with the highest median value of 40K in the Agreste region (667 Bq kg−1). The humid climate of Zona da Mata was associated with the lowest median value of 40K (39 Bq kg−1) and the highest levels of radium. Soils from most parts of the state may be used as building materials without presenting a radiological risk. [ABSTRACT FROM AUTHOR]

This work presents the first comprehensive assessment of ethanol dissolved in rainwater of São Paulo State's sugar cane belt, considering the period from 2012 to 2017. Ethanol concentrations ranged from 0.25 to 20.9 μmol L−1, with a volume-weighted mean (VWM) of 4.67 ± 0.13 μmol L−1 (n = 410). Despite the increasing use of ethanol fuel in Brazil, during the study period, the ethanol concentration in rainwater showed an average decrease of 0.54 μmol L−1 per year, attributed to technological improvements in vehicular fuel combustion and catalysts. Anthropogenic emissions appeared to overwhelm possible seasonal fluctuations of ethanol in rainwater due to biogenic sources or meteorological conditions such as temperature, solar radiation, rainfall amount, rainfall rate, and air mass origin. Higher VWM concentrations were generally observed in dry months, when the production of ethanol in the distilleries was highest and biomass burning increased. Consideration of ethanol oxidation in aqueous media by OH radicals indicated that secondary formation of highly toxic aldehydes is likely to increase with greater use of this biofuel. Dissolution of gaseous ethanol during cloud formation appeared to be a more important mechanism of atmospheric removal of this alcohol, compared to below-cloud processes. The wet flux of ethanol was ca. 3 kg ha−1 year−1 and there were evidences that atmospheric replenishment of this species was fast. Brazil has used ethanol fuel on a large scale since the 1980s, so better understanding of the behavior of this species in the lower troposphere of the study region can provide valuable information to assist in predicting future worldwide impacts of increasing use of this biofuel. Image 1 - Intensive usage of ethanol fuel in Brazil leads to high concentrations in rainwater - Biomass burning may be an important source of atmospheric ethanol - In-cloud gas-liquid solubilization has great influence on the wet flux of ethanol - Photochemical processes can be important to modulate ethanol concentrations in rain - Improvements in vehicle technology can mitigate primary emissions of ethanol [ABSTRACT FROM AUTHOR]

The botanical heterogeneity found in the Atlantic Forest is essential for the survival of fauna in this biome, especially bees because they depend on resources (pollen and nectar) provided by plants. Pollen analysis is one the main tools employed to understand the resources used by bees and provides information that improves the identification accuracy of pollen grains. The objective of this work was to identify the main pollen types used by Apis mellifera L. bees, in a fragment of Atlantic Forest in the southern region of Bahia State. Bee pollen samples were collected from March 2012 to April 2013. The samples were acetolyzed, mounted, and analyzed based on a minimum count of 500 pollen grains. Identifications were made using the literature and the pollen reference library at the Laboratório de Micromorfologia Vegetal. Thirty-five pollen types were morphologically distinguished in the samples, which belong to 20 plant families. The family Fabaceae had the highest pollen richness (9 types), followed by Asteraceae (4), and Anacardiaceae, Myrtaceae and Poaceae (2 each). Arecaceae was present in all of the samples, although it was represented by only one pollen type, followed by Asteraceae and Myrtaceae (>50%). The statistical analysis detected some groups (cluster) in relation to month/pollen richness, but a correlation between environmental variables/pollen richness was not confirmed (p < 0.05). The results show the high apicultural potential of the family Arecaceae and that other factors (such as temperature and rainfall) might influence pollen richness. [ABSTRACT FROM AUTHOR]

This paper reports a laboratory study of an accelerated reoxygenation treatment of polluted water bodies, using hydrogen peroxide (H2O2): conditions such as the discharge of waters from domestic sewers or polluted storm-water resulting from intense rainfall that lead to a reduction in the level of dissolved oxygen (DO). We studied the water from rivers that make up the basin of the Lagoa Rodrigo de Freitas (LRF) lagoon, Rio de Janeiro, Brazil. When intense rainfall coincides with discharge from sewers, the polluted water may reach LRF. This has in the past led to episodes of critical deficit in DO in the waters of the lagoon, resulting in fish kill. To study this, we carried out experiments with water samples taken from the river feeding the lagoon. To study the accelerated reoxygenation of the river waters, we used different doses of H2O2. We concluded that the addition of H2O2 to the waters of the river during polluting events can prevent the level of DO in the lagoon going below a critical value. This treatment resulted in an immediate increase in DO that lasted hours and in the sustainability of the DO above the legal limit 5.0 mg L−1, enough to avoid fish kill. [ABSTRACT FROM AUTHOR]

Natural disasters are the result of extreme or intense natural phenomena that cause severe impacts on society. These impacts can be mitigated through preventive measures that can be aided by better knowledge of extreme phenomena and monitoring of forecasting and alert systems. The city of Petropolis (in a mountainous region of the state of Rio de Janeiro, Brazil) is prone to heavy rain events, often leading to River overflows, landslides, and loss of life. In that context, this work endeavored to characterize the thermodynamic and dynamic synoptic patterns that trigger heavy rainfall episodes and the corresponding flooding of Quitandinha River. More specifically, we reviewed events from the time period between January 2013 and December 2014 using reanalysis data. We expect that the overall description obtained of synoptic patterns should provide adequate qualitative aid to the decision-making processes involved in operational forecasting procedures. We noticed that flooding events were related to the presence of the South Atlantic Convergence Zone (SACZ), frontal systems (FS), and convective storms (CS). These systems showed a similar behavior on high-frequency wind components, notably with respect to northwest winds before precipitation and to a strong southwest wind component during rainfall events. Clustering analyses indicated that the main component for precipitation formation with regard to CS systems comes from daytime heating, with the dynamic component presenting greater efficiency for the FS configurations. The SACZ events were influenced by moisture availability along the vertical column of the atmosphere and also due to dynamic components of precipitation efficiency and daytime heating, the latter related to the continuous transport of moisture from the Amazon region and South Atlantic Ocean towards Rio de Janeiro state. [ABSTRACT FROM AUTHOR]

An analysis of two groups of near‐surface intense cyclonic vortices, one off the southeastern Brazil coast and the other off the Mozambique coast, in the period 1979–2012 is undertaken for comparison of their characteristics with the help of the TRACK algorithm and the NCEP2 Reanalysis data sets. The aim is to understand the nature of intense cyclogeneses in those two subtropical coastal regions. Although the two groups form in almost the same latitude belt and under similar conditions and thus have some common features, they differ in several evolution and movement characteristics. The South American intense cyclones are more frequent. They move rapidly into southern South Atlantic while the African cyclones remain quasi‐stationary during the first 2 days of their life time. Thermal structures show that the Mozambique Channel region presents more conditional instability. The South American intense cyclones present more kinetic energy than their counterparts in the first 2 days. The precipitation around the South American cyclones decreases gradually. The Mozambique Channel cyclones gain kinetic energy after moving away from the Madagascar Island and preserve their baroclinity longer and therefore the mean precipitation rate around their centres remains constant. The sea surface temperature, the geographical features and the circulation characteristics of the two regions are responsible for the differences. Eventually, after 4 days of their formation, cyclones of both the groups join the Southern Hemispheric extratropical storm‐tracks. [ABSTRACT FROM AUTHOR]

Copyright of Tropical Medicine & International Health is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work presents a comparison of two land surface schemes (BATS and CLM4.5) coupled in RegCM4.6 to simulate the local and mesoscale features of the climate over southeastern Brazil. RegCM4.6 simulations nested in ERAINTERIM reanalysis were done for the very wet year of 2010 and both used 5 km of grid spacing. It is important to highlight that in RegCM-CLM4.5 simulation the urban effects were solved. Simulations are evaluated by comparisons with TRMM rainfall estimation and local observed data at metropolitan region of São Paulo city (MRSP). For all southeastern Brazil, the CLM4.5 simulation produces more intense daily rainfall events than using BATS scheme, resulting in larger agreement with TRMM estimates. The main patterns of mean near surface circulation (10 m wind) and rainfall are similar in CLM4.5 and BATS and they are able to simulate the observed mesoscale features of the climate as: the land-sea breeze along the shore and the valley-mountain breezes. CLM4.5 simulates higher temperatures and rainfall rate than BATS over MRSP, which can be the response of the urban effects simulated in CLM4.5. Comparatively, the southeast winds (sea breeze wind) and continental northwest winds are more intense in CLM4.5 than in BATS, which contribute for stronger wind convergence and increases the precipitation rate over the MRSP. At local scale, CLM4.5 shows large agreement with the observations than BATS in simulating the diurnal cycle of the meridional wind. In other words, CLM4.5 is able to simulate the correct time of wind change, from north to south, which is characteristic of the sea breeze observed in MRSP. [ABSTRACT FROM AUTHOR]

This study evaluates the performance of four Near Real-Time (NRT) satellite rainfall products in estimating the spatiotemporal characteristics of different extreme rainfall events in a subtropical catchment in south-eastern Brazil. The Climate Prediction Centre Morphing algorithm (CMORPH), Tropical Rainfall Measuring Mission, Multisatellite Precipitation Analysis in real time (TMPA-RT), the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Global Cloud Classification System (PERSIANN-GCCS), and the Hydro-Estimator are evaluated for monsoon seasons, based on their capability to represent four types of rainfall events distinguished for: (1) local and short duration, (2) long-lasting event, (3) short and spatial extent, and (4) spatial extent and long lasting. Since the events are defined relative to a percentile, the relative performance variation at different threshold levels (75th, 90th, and 95th) is also evaluated. The data from the 13 Automatic Weather Stations (AWSs) for the period from 2007 to 2014 are used as the reference. The results show that the product performance highly depends on the spatiotemporal characteristics of rainfall events. All four products tend to overestimate intense rainfall in the study area, especially in high altitude zones. CMORPH had the best overall performance to estimate different types of extreme spatiotemporal events. The results allow for developing a better understanding of the accuracy of the NRT products for the estimation of different types of rainfall events. [ABSTRACT FROM AUTHOR]