Ashish Mishra

and 1 more

Urban Heat Island (UHI) effects have significant implications on the microclimatic conditions in urban environments, impacting human health, energy consumption, and overall urban planning. This study aims to assess the diurnal intensity of UHI in a microclimatic urban setting by adopting the Local Climate Zone (LCZ) classification approach. We utilized a combination of remote sensing data, ground-based measurements, and LCZ classification to analyze the temporal and spatial variation of UHI intensity throughout the day and night. The study area, Dehradun city, a densely populated urban area situated in the valley region of Himalayas, exhibited diverse LCZs, including compact low-rise, dense trees, and open spaces. Using satellite-derived land surface temperature (LST) data and hourly in-situ measurements, we quantified the UHI effect during daytime and nighttime hours. The results revealed distinct diurnal patterns of UHI intensity among different LCZs, with peak intensity occurring during late afternoon and early evening hours. Furthermore, we investigated the impact of vegetation and built-up characteristics on UHI variation, highlighting the cooling effect of green spaces and the amplifying effect of impervious surfaces. This research contributes to a better understanding of microclimatic urban environments and their relation to UHI dynamics, providing valuable insights for urban planners, policymakers, and researchers aiming to mitigate heat-related issues and promote sustainable urban development. The findings underscore the importance of considering local land-use patterns and urban morphology when assessing and managing UHI effects.

Mani Kanta Malla

and 1 more

Extreme precipitation events from the western disturbances have significant impacts on the water management and ecosystem services in the Upper Indus basin, a part of the Hindukush Himalayan region. Further, there are changes in the duration, intensity, spatial extent and frequency of extreme events due to climate change. In this domain, a few studies have assessed the impact of climate change in the study area with limited data. There will be high uncertainty in the outcomes obtained from the investigation of extreme events with limited data. Therefore, a comprehensive analysis of extreme precipitation events from western disturbances considering high resolution with long-term data is required in the study area. Accordingly, In the present study, Precipitation based ETCCDI Indices are calculated for every year, and non-parametric Mann-Kendall test is applied Sen slope is calculated to detect the changes in the monthly precipitation during the winter season for the period 1901-2019. The findings of the present study reveal the northwest region has an increasing trend in RX1day extreme precipitation of 1.85 mm per decade in December, and the rate has amplified due to the effect of western disturbances in January and February. Also, the pattern of RX5day extreme precipitation is consistent in January and February. Overall the wetness in increasing over the north-west part of the study area In recent decades, the northwest region of the upper Indus basin had faced more extreme events with severe impacts due to western disturbances, and outcomes from the study can improve the understanding of extreme events.