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Jaspura watershed a part of Yamuna basin is situated in drought prone area lying in the Banda district of Bundelkhand region, Uttar Pradesh, India. The drastic decline of groundwater level and consistently drying up of the phreatic aquifer has led to the acute shortage of groundwater in the study area. The situation is further aggravated due to base flow in the areas adjoining the major order streams. To mitigate such problem in study area, MIF technique, combined with RS and GIS, has been effectively used to delineate the potential recharge zone using seven thematic layers, viz., LULC, soil, slope, drainage density (Dd), geomorphology, depth to water level map of post-monsoon, and groundwater fluctuation map. Relative rates and weight of each influencing factor have been calculated on the basis of major and minor effect of these thematic layers. Based on their influence on groundwater recharge capacity using seven thematic layers under potential zone, five classes under artificial recharge have been identified, viz., very high (96.4 km2), high (157.4 km2), moderate (146.1 km2), low (72.9 km2), and very low (34.2km2). The runoff in 15 micro-watersheds has been estimated using SCS-CN approach. Integration of runoff and potential recharge zone has yielded the suitable sites and type of groundwater recharge structure. On the basis of its percolation tank (PT), check dam (CD) and sub-surface dam (SD) have been identified as feasible and suitable groundwater recharge structure.

To estimate the prevalence and determine risk factors for dry eye disease (DED) in geographically diverse regions of India.

Satellite observations and Meso‐NH model simulations are used to investigate an intense dust storm over north India in June 2018Dust is mostly confined below 2 km in the monsoon flow over the Thar desert, northwest India and at ~3 km along the Ganges ValleyThe dust was accumulated in an arc‐shaped cloud in the convergence zone between the southwesterlies and the northwesterlies: the ITD A severe dust storm occurred over north India during 12–16 June 2018 is analyzed using satellite observations, reanalysis, ground‐based measurements, and model (Meso‐NH) simulations focusing on the dynamic processes that caused the dust‐storm generation, uplift, and propagation as well as its impacts on air quality. The initial dust emission was triggered by strong near‐surface southwesterlies (~15–20 m s−1) associated with the monsoon flow advancing northward, in response to the deepening of the thermal low over the Thar desert. The convergence between the northwesterlies and the monsoon flow along the Intertropical Discontinuity region caused high dust accumulation over northwest India in an area of weak winds. Convective mixing during daytime favors the vertical transport of dust to higher altitudes above the monsoon flow, but the towering Himalayas and the associated return northerly flow aloft play a blocking role leading to dust accumulation at heights between 1 and 3 km over northwest India. The prevailed northwesterlies in the middle troposphere favor the eastward transport of the dust plumes along the Ganges valley, helping to evacuate the dust toward east India. Based on Meso‐NH model simulations, the dust storm was associated with dust loads higher than 30 gm−2and AODs higher than 3, in agreement with MODIS observations. The impact of the dust storm on the spatial‐temporal evolution of the PM10and PM2.5mass concentrations is studied using data from 23 air‐quality stations over northern India, indicating daily PM10peaks reaching at ~900 μg m−3, implying a severe degradation of air quality.

The aerosol direct radiative effects (DRE) in the ultraviolet, shortwave, and longwave range due to an unusual dust storm during 21 March 2012 have been quantified from surface measurements of aerosol optical depth (AOD) and radiation fluxes at Delhi, a western Indo Gangetic Plain station. The intrusion of dust over Delhi caused an increase in daily average AOD at 500 nm from 0.6 to 0.8, with a corresponding decrease in Angstrom exponent from 0.4 to subzero value. The dust severely affected the incoming solar radiation flux in the UV, shortwave, and longwave regions. The DRE at surface in the UV and shortwave regions decreased from −4.6 to −5.9 Wm−2and from −68 to −86 Wm−2, respectively, while the longwave DRE increased from 27 to 45 Wm−2. Dust intrusion changes AOD from .58 to .74 and alfa from .43 to ‐.02Downwelling UV and SW flux decrease from 9 to 7 Wm‐2 and 221 to 199 Wm‐2DRE due to UV, SW decreased by 28% and 26%, and LW increased by 40%