nasa-gesdisc/es-publications-researchareas huggingface dataset:
Improving Hourly Precipitation Estimates for Flash Flood Modeling in Data-Scarce Andean-Amazon Basins: An Integrative Framework Based on Machine Learning and Multiple Remotely Sensed Data (2021)

Accurate estimation of spatiotemporal precipitation dynamics is crucial for flash flood forecasting; however, it is still a challenge in Andean-Amazon sub-basins due to the lack of suitable rain gauge networks. This study proposes a framework to improve hourly precipitation estimates by integrating multiple satellite-based precipitation and soil-moisture products using random forest modeling and bias correction techniques. The proposed framework is also used to force the GR4H model in three Andean-Amazon sub-basins that suffer frequent flash flood events: upper Napo River Basin (NRB), Jatunyacu River Basin (JRB), and Tena River Basin (TRB). Overall, precipitation estimates derived from the framework (BC-RFP) showed a high ability to reproduce the intensity, distribution, and occurrence of hourly events. In fact, the BC-RFP model improved the detection ability between 43% and 88%, reducing the estimation error between 72% and 93%, compared to the original satellite-based precipitation products (i.e., IMERG-E/L, GSMAP, and PERSIANN). Likewise, simulations of flash flood events by coupling the GR4H model with BC-RFP presented satisfactory performances (KGE* between 0.56 and 0.94). The BC-RFP model not only contributes to the implementation of future flood forecast systems but also provides relevant insights to several water-related research fields and hence to integrated water resources management of the Andean-Amazon region.

Research areas: Validation
The Greater Mekong Subregion (GMS) and tropical expansion: A regional study of convection and precipitation (2022)

A series of data sets including brightness temperature from HIRS-UTWV, high cloud cover, precipitation and evaporation from ERA-Interim reanalysis data, and deep convective cloud from ISCCP were used to examine the latitudinal changes of the Hadley cell in the Greater Mekong Subregion (GMS) over the 19792018 period. In the study region, a pronounce poleward expansion was found during the winter season using three metrics of expansion: latitude of maximum brightness temperature associated with the anticyclonic center; latitude of zero crossing of precipitation minus evaporation, marking the extent of the tropical region; and latitude where high cloud cover reaches 50% of its maximum tropical value. However, no trends were discovered for the summer season. During the study period, there was an increase in equatorial convection as indicated by increased high cloud cover features. When precipitation minus evaporation was less than 0, there was diminishing dry zone evidence.

Research areas: Atmospheric/Ocean Indicators
An ozonesonde evaluation of spaceborne observations in the Andean tropics (2022)

Satellite observations of ozone in the tropics have feedback from in situ measurements at sea level stations, but the tropical Andes is a region that is yet to be included in systematic validations. In this work, ozonesondes launched from the equatorial Andes were used to evaluate total column ozone (TCO) measured by spaceborne sensors TROPOMI/S5P (20182021), GOME-2/MetOp-B, OMI/Aura, and OMPS/Suomi NPP (20142021). Likewise, we evaluated tropospheric column ozone (TrCO) measured by the first two. Additionally, we evaluated TCO and TrCO from reanalysis products MERRA-2 and CAMS-EAC4. Results indicate that TCO observations by OMPS/Suomi NPP produce the closest comparison to ozonesondes ( 0.2% mean difference) followed by OMI/Aura (+ 1.2% mean difference). Thus, they outperform the sensor with the highest spatial resolution of current satellite measurements, namely TROPOMI/S5P (+ 3.7% mean difference). This overprediction is similar to the one encountered for GOME-2/MetOp-B (+ 3.2% mean difference). A positive bias with respect to soundings was also identified in TrCO measured by TROPOMI/S5P (+ 32.5% mean difference). It was found that the climatology used by TROPOMI overpredicts ozone in the troposphere when compared with the mean of Andes measurements, while both data sets are essentially the same in the stratosphere. Regarding reanalysis products, MERRA-2 compares better to ozonesondes than CAMS, both for TCO and TrCO (mean differences are 1.9% vs. 3.3%, and 11.5% vs. 22.9%, respectively). Identifying spaceborne ozone measurements that currently perform the best over the region is relevant given the present conditions of rapidly changing atmospheric composition. At the same time, ozonesonde data in this work offer an opportunity to improve satellite observations in the Andean tropics, a challenging region for space measurements.

Research areas: Validation
The Relation Between Net Primary Productivity And Human Activities For Three Biomes In Bahia State, Brazil (2023)

Brazilian biomes are hotspots of global biodiversity, important biomass producers and, consequently, help maintain the worlds carbon balance. Net primary production (NPP) is a variable used to determine carbon uptake by land cover. As environmental factors and human activities vary, net primary production increases or decreases. This study aimed to evaluate NPP in three Brazilian biomes  Atlantic Forest, Cerrado, and Caatinga  in the state of Bahia for the last 17 years, and to understand its relationship with human activities by analyzing burned areas, as well as interrelated environmental factors, such as climate variability and soil heat flux, using remote sensing. Using the MOD17 dataset, we find evidence that the Atlantic Forest biome is the one that absorbs more carbon in comparison to the Caatinga and Cerrado biomes, with a mean annual net primary production in each one of these three biomes equal to 1,227.89 g C m-2, 913.81 g C m-2, and 803.56 g C m-2, respectively. The years of El Nino influenced all biomes, and the results showed a strong relationship between climate and NPP in the studied biomes, especially in Caatinga, which is the most sensitive to climatic variations. Besides these results, we find evidence that, in all these biomes, the NPP dynamics have been affected by the increase in land use for agricultural and livestock activities, mainly because of deforestation and burning.

Research areas: Ecosystems, Atmospheric/Ocean Indicators, Habitat Conversion/Fragmentation
Early-life environmental exposures and anaemia among children under age five in Sub-Saharan Africa: An insight from the Demographic & Health Surveys (2022)

Background
Reports show that the majority (60%) of children under age five years in Sub-Saharan Africa are anaemic. Studies in the region have mainly focused on the effect of individual, maternal and household socioeconomic status on the prevalence of anaemia. Currently, there is limited understanding of the association between early-life environmental exposures and anaemia among children in Sub-Saharan Africa.
Objective
The study examines the association between early-life environmental exposures and anaemia among children under five in Sub-Saharan Africa.
Methods
The study used health and demographic data from the Demographic and Health Survey (DHS) program and environmental data from NASA's Geospatial Interactive Online Visualization ANd aNalysis Infrastructure (GIOVANNI) and Atmospheric Composition Analysis Group. Three exposure periods were defined for the study, namely: in-utero, post-utero and cumulative life exposures. Multilevel mixed-effect models were used to assess the associations between environmental exposures and anaemia in each exposure period.
Results
The findings show that 63% of children in the study were anaemic. It also reveals that mean PM 2.5 exposure for in-utero (34.93 gm3), post-utero (35.23 gm3) and cumulative exposure (35.08 gm3) were seven times higher than the new air quality guideline WHO recommended. A 10 gm3 increase in in-utero, post-utero and cumulative PM 2.5 exposures was associated with 4% to 5% increase in the prevalence of anaemia among children. A 10ppbv increase in in-utero, post-utero and cumulative carbon monoxide exposures was associated with 1% increase in the prevalence of anaemia among children. The spatial risk distribution maps show that socioeconomic factors modify the spatial risk distribution pattern.
Conclusion
The findings of the study suggest that early-life exposure to ambient air pollution is significantly associated with anaemia among children in Sub-Saharan Africa. Thus, policies aimed at addressing air quality should be incorporated into targeted interventions for anaemia among children in the region.

Research areas: Public Health, Air Quality
Investigation of Aeolian Dust Deposition Rates in Different Climate Zones of Southwestern Iran (2021)

Dust and atmospheric particles have been described in southwestern Iran primarily in terms of load, concentration and transport. The passive deposition, however, has been discussed inadequately. Therefore, the relationships between different climate zones in southwestern Iran and dust deposition rates were quantified between 2014 and 2017 using both space- (second modern-era retrospective analysis for research and applications, version 2 reanalysis model) and ground-based (eolian ground deposition rate) tools. In addition, the surface meteorological records, including the wind patterns favoring the occurrence of dust events, were examined. A hot desert climate (BWh), hot semi-arid climate (BSh), and temperate hot and dry summer climate (Csa) were identified as the three dominant climate regions in the study area, exhibiting the highest average dust deposition rates. In this study, correlations between the most relevant climate patterns and deposition rate weather parameters were found to describe a regions deposition rate when a dust event occurred. Based on these results, the BSh and Csa regions were found to be associated with the seasonal cycle of dust events in March, April, and May, revealing that in the long run meteorological conditions were responsible for the varying dust deposition rates. Relatively, precipitation and temperature were the two major factors influencing dust deposition rates, not wind speed. Moreover, the peak seasonal deposition rates in the spring and summer were 8.40 t km2 month1, 6.06 t km2 month1, and 3.30 t km2 month1 for the BWh, BSh, and Csa climate regions, respectively. However, each of these climate types was directly related to the specific quantity of the dust deposition rates. Overall, the highest dust deposition rates were detected over the years studied were 100.80 t km2 year1, 79.27 t km2 year1, and 39.60 t km2 year1 for BWh, BSh, and Csa, respectively.

Research areas: Air Quality
Integrating Satellite Rainfall Estimates with Hydrological Water Balance Model: Rainfall-Runoff Modeling in Awash River Basin, Ethiopia (2021)

Hydrologic models play an indispensable role in managing the scarce water resources of a region, and in developing countries, the availability and distribution of data are challenging. This research aimed to integrate and compare the satellite rainfall products, namely, Tropical Rainfall Measuring Mission (TRMM 3B43v7) and Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record (PERSIANN-CDR), with a GR2M hydrological water balance model over a diversified terrain of the Awash River Basin in Ethiopia. NashSutcliffe efficiency (NSE), percent bias (PBIAS), coefficient of determination (R2), and root mean square error (RMSE) and Pearson correlation coefficient (PCC) were used to evaluate the satellite rainfall products and hydrologic model performances of the basin. The satellite rainfall estimations of both products showed a higher PCC (above 0.86) with areal observed rainfall in the Uplands, the Western highlands, and the Lower sub-basins. However, it was weakly associated in the Upper valley and the Eastern catchments of the basin ranging from 0.45 to 0.65. The findings of the assimilated satellite rainfall products with the GR2M model exhibited that 80% of the calibrated and 60% of the validated watersheds in a basin had lower magnitude of PBIAS (

Research areas: Validation
Our Carbon Debt: A Curriculum for Interdisciplinary Education on Climate Change (2022)

Although academic departments often prepare students through education on the scientific foundations of climate change from the perspectives of such fields as conservation biology, environmental geoscience, or environmental geology, our college aims to provide a broader perspective on the climate change issue. To do so, we engage students in a more targeted manner, based on their disciplinary and program focus. For some students, this involves application of geotechnology and modeling applications so they are more informed on the technology necessary for monitoring greenhouse gases and their related impacts. For others, we focus more on promoting dialogue on the educational and societal implications of climate change by integrating perspectives from environmental economics, entrepreneurship, art, and social foundations of education through active learning activities. In this chapter, we present an interdisciplinary perspective on sustainability rooted in the concept of climate debt.

Research areas: Validation
PM10 aerosol enhancement in the anticyclonic anomalies caused by the East Asian spring warming of 2021 (2023)

This study analyzed the PM10 aerosol enhancement caused by East Asian atmospheric warming during transboundary transport in March of 2021. It was found to be cooled near the north polar area and to have shifted the polar vortices northward over the East Asian region in the mid-troposphere. The Siberian high was weakened and the East Asian region was characterized by a positive air temperature anomaly and negative zonal wind speeds. The increasing rate of air temperature anomalies at 2 m was higher in the high latitude areas over 40N in Mongolia and northeastern China, causing a decrease in zonal wind speeds at 10 m over eastern China and Korea. The anomalous variations of the MODIS-induced aerosol optical depth (AOD) were found to be positive with the highest value of +0.93 in the area ranging from northeastern China to Korea, despite the recent decreasing trends. The positive anomalous region of the MODIS-induced AOD was correlated with positive air temperatures and negative zonal wind speeds, causing enhanced formations of secondary aerosols in the atmosphere. As cold northerly winds were suppressed in the East Asian region, anomalous high pressures (anticyclonic anomalies) developed frequently in eastern China and moved to Korea. The Weather Research and Forecasting model to which meteorological and climate data were applied coupled with Chemistry (WRF-Chem) simulations on increases in the PM10 enhancement ratio, indicating enhanced formation amounts, during transboundary transport for the period of March 1315, 2021. An air mass near the high terrain surface over eastern China under the backward side of an anticyclone warmed and moved toward the relatively low terrain of the Yellow Sea and Korea in keeping with the height. Air temperature inversion developed in the anomalous warmer center in the mid-troposphere, reaching the surface of the Yellow Sea and Korea. High PM10 concentrations were constrained near the shallow inversion layer. Furthermore, the PM10 enhancement ratio showed a positive level over the Yellow Sea with nearly zero anthropogenic emissions on the surface, gradually increasing at a rate of approximately 60% in Korea. The hourly contribution by the warming-induced PM10 enhancement (PM10 CbWIE) was calculated and found to be at the highest level of 70% in Seoul, Korea. Among PM10 secondary inorganic aerosols, nitrate formations were enhanced during transboundary transport in the warming-induced anticyclone with reactions rich in ammonium. While the sulfate enhancement ratio reached a positive level over the Yellow Sea, the gradual decrease during transboundary transport may be reflected by the decreased emissions of sulfur dioxide in eastern China.

Research areas: Air Quality, Atmospheric/Ocean Indicators
Absorption Angstrom Exponent of Dust Aerosols Over the Tarim Basin (2021)

The first ever (to our knowledge) long-term characteristics of aerosol absorption optical depth (AAOD) and then absorption Angstrom exponent (AAE) over the Tarim Basin during 20052018 are investigated based on the latest Ozone Monitoring Instrument (OMI) retrievals. This paper aims at evaluating the AAOD and AAE in terms of annual, seasonal, and monthly variations, and referential AAE values of dust aerosols over the Tarim Basin. Our results reveal that the AAOD increases by a factor of nearly 2 from 2015 to 2018, with yearly average values from 0.08 to 0.14 and from 0.04 to 0.07 at 388 and 500 nm, respectively, indicating that the situation of dust aerosol pollution in the Tarim Basin has become severe in recent years. The AAE based on the AAODs at wavelengths of 388 and 500 nm over the Tarim Basin exhibits large variations, with a range of 2.53.8. The seasonality of AAOD depicts maximum levels in spring, moderate levels in winter and autumn, and minimum levels in summer, whereas the AAE shows a distinctive pattern with high values in summer and low levels in winter. The monthly mean AAOD values vary by twofold, while monthly average AAE is in a range of 2.83.3, with the lowest value in February and the highest in June. The daily AAE between 388 and 500 nm for dust episodes is found to be in a range of 3.23.6, with a mean of 3.3, which hopefully provides typical AAE values of dust aerosols over the Tarim Basin.

Research areas: Air Quality
Situation of Urban Mobility in Pakistan: Before, during, and after the COVID-19 Lockdown with Climatic Risk Perceptions (2021)

The coronavirus pandemic (COVID-19) has impacted the usual global movement patterns, atmospheric pollutants, and climatic parameters. The current study sought to assess the impact of the COVID-19 lockdown on urban mobility, atmospheric pollutants, and Pakistans climate. For the air pollution assessment, total column ozone (O3), sulphur dioxide (SO2), and tropospheric column nitrogen dioxide (NO2) data from the Ozone Monitoring Instrument (OMI), aerosol optical depth (AOD) data from the Multi-angle Imaging Spectroradiometer (MISR), and dust column mass density (PM2.5) data from the MERRA-2 satellite were used. Furthermore, these datasets are linked to climatic parameters (temperature, precipitation, wind speed). The KruskalWallis H test (KWt) is used to compare medians among k groups (k > 2), and the Wilcoxon signed-rank sum test (WRST) is for analyzing the differences between the medians of two datasets. To make the analysis more effective, and to justify that the variations in air quality parameters are due to the COVID-19 pandemic, a Generalized Linear Model (GLM) was used. The findings revealed that the limitations on human mobility have lowered emissions, which has improved the air quality in Pakistan. The results of the study showed that the climatic parameters (precipitation, Tmax, Tmin, and Tmean) have a positive correlation and wind speed has a negative correlation with NO2 and AOD. This study found a significant decrease in air pollutants (NO2, SO2, O3, AOD) of 3040% in Pakistan during the strict lockdown period. In this duration, the highest drop of about 28% in NO2 concentrations has been found in Karachi. Total column O3 did not show any reduction during the strict lockdown, but a minor decline was depicted as 0.38% in Lahore and 0.55% in Islamabad during the loosening lockdown. During strict lockdown, AOD was reduced up to 23% in Islamabad and 14.46% in Lahore. The results of KWt and WRST evident that all the mobility indices are significant (p < 0.05) in nature. The GLM justified that restraining human activities during the lockdown has decreased anthropogenic emissions and, as a result, improved air quality, particularly in metropolitan areas.

Research areas: Air Quality, Environmental Impacts
The Effect of COVID-19 on the Atmospheric Parameters Over the Indian Subcontinent (2021)

In the present study, the atmospheric concentrations of various pollutants over the Indian subcontinent
before the COVID-19 (during 2019) and during COVID-19 phases (2020) were studied. The COVID-19
has created a negative impact on the countrys economy but has positivity over the atmospheric
resources. The levels of carbon monoxide (CO), nitrogen dioxide (NO 2 ), and UV aerosol index were
assessed using satellite images for the two different phases. The obtained results can be interpreted
and can be substantiated with the lockdown effect due to the COVID -19 pandemic. The pollutants
are mostly emitted from anthropogenic sources like vehicular emissions, industrial emissions, power
plants, construction works, commercial and institutional places. It was evident that the levels of carbon
monoxide, nitrous dioxide and aerosols levels have drastically decreased during the lockdown period.
Hence, it can be concluded that COVID-19 has cleaned the atmospheric pollution as well as climate
change scenario and nature on its own.

Research areas: Air Quality, Environmental Impacts
Satellite Monitoring of Environmental Solar Ultraviolet A (UVA) Exposure and Irradiance: A Review of OMI and GOME-2 (2021)

Excessive exposure to solar ultraviolet (UV) radiation has damaging effects on life on Earth. High-energy short-wavelength ultraviolet B (UVB) is biologically effective, influencing a range of dermal processes, including the potentially beneficial production of vitamin D. In addition to the damaging effects of UVB, the longer wavelength and more abundant ultraviolet A (UVA) has been shown to be linked to an increased risk of skin cancer. To evaluate this risk requires the monitoring of the solar UVA globally on a time repetitive basis in order to provide an understanding of the environmental solar UVA irradiance and resulting exposures that humans may receive during their normal daily activities. Satellite-based platforms, with the appropriate validation against ground-based instrumentation, can provide global monitoring of the solar UVA environment. Two satellite platforms that currently provide data on the terrestrial UVA environment are the ozone monitoring instrument (OMI) and the global ozone monitoring experiment (GOME-2). The objectives of this review are to provide a summary of the OMI and GOME-2 satellite-based platforms for monitoring the terrestrial UVA environment and to compare the remotely sensed UVA data from these platforms to that from ground-based instrumentation.

Research areas: Public Health
Ionospheric and atmospheric perturbations due to two major earthquakes (M >7.0) (2021)

The perturbation produced in the atmosphere/ionosphere associated with earthquake precursors during seismic activity of two major earthquakes which occurred on (1) 24 June 2019 in Indonesia (M = 7.3) and (2) on 19 August 2018 at Ndoi, Fiji (M = 8.2), are studied. Based on statistical analysis of total electron content (TEC) data, the presence of ionospheric perturbations 5 days before and after the main shock are found, which depends on the distance as well as direction of observation point from the epicentre. In general, ionospheric perturbations after the EQ at all the stations are found larger than that before the EQ. Probable mechanisms behind these perturbations associated with EQ are also being discussed. The ionospheric perturbations are observed at stations which are at larger distances from the epicentre, but not observed over other stations in different directions which are comparatively closer to the epicentre. These results suggest that seismic induced ionospheric anomaly is not isotropic in nature. Ozone data from three satellites: AIRS, OMI, and TOMS-like and MERRA-2 model are also analyzed 5 days before the EQ day and compared to the monthly average level. A strong link between anomalous variation in ionospheric TEC and atmospheric ozone data prior to both the EQs is noticed.

Research areas: Earthquakes