Mohd Nazish Khan

Large-scale open-pit mining is a major driver of land-cover transformation in arid and semi-arid environments, yet few studies integrate spatial driver analysis with long-term predictive modeling in such landscapes. This study examines spatiotemporal land use/land cover (LULC) change at the...

The Samarkand city is located on the left bank of the Zarafshan River. However, the city experiences an acute crisis of water due to rapid socio-economic development and population growth, resulting in increasing water demand. A heavy reliance on groundwater was made to meet these water demands, leading to its overexploitation and resulting in a significant decline in groundwater levels, which requires urgent attention to explore potential mediums for replenishing the groundwater. The current study focuses on the potential rainwater harvesting and artificial recharge zones by analyzing the seven variables like geology, soil types, land use and land cover, slope, curvature, drainage density, and distance from lineaments. The potential artificial recharge locations for rainwater harvesting and artificial recharge are identified by employing the analytical hierarchy process (AHP) using a geographic information system (GIS). The highest scores (ranked good), indicate the most suitable locations for rainwater harvesting and artificial recharge, covering an area of about 10 km2 (18.9%). Recharge can be made during rainfall events, where relatively large volumes of water become available relatively quickly and accumulate at surface depressions. The runoff can be stored in groundwater by enhancing its infiltration through gravity injection wells. The weighted overlay method was implemented to identify potential rainwater harvesting and artificial recharge locations using seven parameters: geology, soil type, land use and land cover, slope, curvature, drainage density, and distance from lineaments.

On May 26, 2024, Delhi experienced an extreme heat event, with temperatures soaring to record-breaking levels, exceeding 52°C, which was later revised to 46°C (114.8°F) by the India Meteorological Department.Amidst the controversy surrounding sensor failures, this study examines land surface temperature (LST) in Delhi using Landsat 9 OLI and MODIS Aqua data, focusing on the extreme heat event of May 26, 2024. This date was selected due to anticipated extreme heat and the availability of data. Satellite observations revealed temperatures as high as 56°C, with distinct spatial variations across Delhi. The western region recorded the highest temperatures, while the eastern region, influenced by the Yamuna River, exhibited cooler conditions. Emissivity values from Landsat (0.970–0.984) and MODIS (0.973–0.987) were analyzed, showing a strong correlation with surface temperatures: lower emissivity values corresponded to greener areas and lower temperatures, whereas higher values were linked to elevated temperatures. The study highlights the impact of surface characteristics on thermal behavior and underscores the role of urban heat islands (UHIs), particularly in northwestern Delhi. These UHIs, driven by industrial activity, dense settlements, and low-albedo materials, resulted in 2–4°C temperature differences between urban and rural areas, posing health risks to vulnerable populations. Mitigation strategies such as expanding green spaces and relocating high-emission industries are recommended to alleviate these risks. Despite the absence of field data, global studies validating Landsat and MODIS-derived LST support the accuracy of this study’s findings. Thus, the spatial pattern of LST remains reliable even with minor errors ranging from 1 to 2 °C. The study will help for strategic planning and mitigation measures to address extreme heat events in urban areas.

The Ramganga River flows from north to south and drains the northeastern (Lesser Himalaya) of the Himalaya. It transects with numerous active faults, thrusts, and litho-tectonic units before the confluence with the Saryu River at Rameshwar.The present study aimed to determine the virtue of geomorphic indices in appraising the status of neotectonic activity in the Ramganga River Valley, Eastern Kumaun, Himalaya. The watersheds and drainage network were extracted using the Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) DEM at 50000 and 100 Pixels threshold, derived18 sub-watersheds and detailed drainage network. Further, this study deciphered the relative neo-tectonic activity of the Ramganga river using the Index of Relative Active Tectonics (IRAT) based on various geomorphic indices Bifurcation Ratio (Br), channel sinuosity (Cs), Asymmetry Factor (Af), Hypsometric Integral (HI), Basin Elongation Ratio (Re), Drainage Density (Dd), Drainage Texture (Dt), and Stream Length Gradient (SL). These indices were classified into high, moderate and low to provide a rank to sub-basin for deriving the IRAT. The northeastern bank of Ramganga River shows high neo-tectonic activity, viz., stream length gradient (500- 1688), channel sinuosity (1.41- 1.48), and valley floor width to height ratio (0.11- 0.34) than southwestern parts.

Wind farm suitability analyses have been carried out to demarcate the potential zones in the Middle Zarafshan River basin. Uzbekistan’s major cities occupy the middle and lower Zarafshan Valley, which needs to allocate and develop wind energy farms to restore sustainability. In the current study, the Middle Zarafshan valley was assessed to provide a synoptic view of potential zones for wind energy. This study aimed to develop a geospatial method to identify optimal locations in the valley. To accomplish this task, five criteria were considered: wind speed, slope, distance from the transmission network, road network, land use, and land cover. Further, each criterion was assigned a weight according to expert opinions and published research outcomes. In addition, a maximum of 45 % weight was assigned to wind speed, followed by land use, land cover, slope, and others. Further, these criteria were categorized into four classes viz., unsuitable, less suitable, moderately suitable, and highly suitable. Further, different thematic layers were produced to realize this study. Wind speed maps were derived at different heights to calculate the results and integrate them with other derivatives. The findings of this study show that the maximum intensity of winds received at 100 m height or more, and more than 40 % area of the study area was estimated suitable for wind energy exploitation.

The present paper addresses a comprehensive historical assessment of water consumption, demand, and supply in Saudi Arabia, along with future projections regarding water balance, in terms of demand and supply by source in various sectors. Being an arid region, Saudi Arabia experiences scorching heat, low precipitation, a high rate of potential evaporation, and the absence of permanent water bodies over the territory. Groundwater contributes almost 61% of total available water, while the recharge rate is negligible. However, few widyan (ephemeral streams) systems exists to satisfy water demand, which could contribute to approximately one year of domestic water consumption if managed efficiently. The study also predicts water consumption scenarios for the next three consecutive development plans, i.e., the 10th plan (2015–2019), 11th plan (2020–2024), and 12th plan (2025–2029). The analysis shows that water consumption may decline significantly in the future, if the present rate of decline continues. Scenario I, if the current rate is assumed, provides a decrease in consumption of 14.36, 12.66, and 11.15 BCM for 10th, 11th, and 12th plans, respectively. Moreover, the domestic and industrial sectors will consume more water in the future. In the same way, scenarios II and III represent a decline in total water consumption, along with that of agriculture, while domestic and industrial water usage would increase, thus improving environmental sustainability.

The Goriganga river basin lies in the Northeast Kumaon Himalaya and is found suitable for assessing active tectonics at different scales. In addition, this study focuses on the assessment of ongoing tectonic activity through morphotectonic measurement of the Goriganga river basin, which is an ideal location for such analysis and Goriganga river basin transects with three major domains of Himalaya’s lithotectonic structures viz., Tethys, Vaikrita, and Lesser Himalayan Domain. To realize this task, the ASTER Digital Elevation Model was used and found suitable to extract different morphotectonic indices such as Stream Length Gradient (SL), Hypsometric Integral (HI), Length of Overland Flow (Lg), Drainage Density (Dd) and Channel Sinuosity (Cs). Results of these important indices, including SL (18- 4737) HI (0.26- 0.57), and Lg (0.08- 0.19) depict greater variability in the tectonics activity while these values are correspondingly high in the close proximity of lithotectonic units, showing strong tectonic activity. In the extreme south, the Rauntis Gad basin strongly influences tectonism due to transecting syncline and anticline as well as unknown active faults.

This paper summarizes the spatial-temporal analysis of aerosol dust loading and aerosol dust extinction over the Indian subcontinent for identifying trends and patterns for a period of 40 years from 1980 to 2019. These analyses are based on the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) data using Modern-Era Retrospective Analysis for Research and Applications, Version 2. The high-resolution data of CALIPSO indicate a high concentration of dust column mass density over the northwestern part of India. It increases from central India to Rajasthan and Jammu & Kashmir regions. Mean dust aerosol optical depth also suggests an increase in the dust loading over northwestern part of the country.