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Among several devastating natural hazards, flooding is a common and serious threat to society causing huge loss of lives, properties, and infrastructure throughout the world. The intensity and frequency of this extreme weather event are expected to increase due to significant changes in the present‐day climate and land use and land cover (LULC) pattern. India has a very systematic and organized structural program and policies but lacks proper implementations, and adverse effect of climate change and the extreme event goes on in society. This paper is an analysis of floods in India and hazards due to climate change and LULC change patterns. Three models, namely "Eco‐biogeography‐based optimization (EBO), Random forest (RF), and Support vector machine (SVM)" were used to obtain the final output to prepare a "Flood susceptibility map". The result was validated through the "Receiver operating characteristics (ROC)" with "Area under curve (AUC)" values. The future rainfall scenario has been estimated by considering the "General circulation models" through different "shared socioeconomic pathways (SSPs)". The values of AUC are 0.915 (EBO), 0.887 (RF), and 0.869 (SVM), respectively. After consideration of different SSPs, the result shows that there is an increasing tendency of flood hazards in the projected period. Among all the employed modelling approaches, the EBO model has notable potential in delineating the possible flood‐prone regions for effective flood planning and management. Decision‐makers can benefit from country‐specific information and regional planner to implement sustainable and long‐term measures to overcome this type of hazardous situation. [ABSTRACT FROM AUTHOR]

This paper presents an approach to model the expected impacts of climate change on irrigation water demand in a reservoir command area. A statistical downscaling model and an evapotranspiration model are used with a general circulation model (GCM) output to predict the anticipated change in the monthly irrigation water requirement of a crop. Specifically, we quantify the likely changes in irrigation water demands at a location in the command area, as a response to the projected changes in precipitation and evapotranspiration at that location. Statistical downscaling with a canonical correlation analysis is carried out to develop the future scenarios of meteorological variables (rainfall, relative humidity (RH), wind speed ( U2), radiation, maximum (Tmax) and minimum (Tmin) temperatures) starting with simulations provided by a GCM for a specified emission scenario. The medium resolution Model for Interdisciplinary Research on Climate GCM is used with the A1B scenario, to assess the likely changes in irrigation demands for paddy, sugarcane, permanent garden and semidry crops over the command area of Bhadra reservoir, India. Results from the downscaling model suggest that the monthly rainfall is likely to increase in the reservoir command area. RH, Tmax and Tmin are also projected to increase with small changes in U2. Consequently, the reference evapotranspiration, modeled by the Penman-Monteith equation, is predicted to increase. The irrigation requirements are assessed on monthly scale at nine selected locations encompassing the Bhadra reservoir command area. The irrigation requirements are projected to increase, in most cases, suggesting that the effect of projected increase in rainfall on the irrigation demands is offset by the effect due to projected increase/change in other meteorological variables (viz., Tmax and Tmin, solar radiation, RH and U2). The irrigation demand assessment study carried out at a river basin will be useful for future irrigation management systems. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive analysis on the past and future changes in precipitation extremes and quantifies the relative contributions from its frequency and intensity across India, considering five extremeness levels, denoted by 95th, 99th, 99.9th, 99.95th, and 99.97th percentile. Gridded station‐based observations from the historical period (1951–2020) and simulations from 14 General Circulation Models for the future (2021–2100), participating in the Coupled Model Intercomparison Project phase 6 (CMIP6) are considered. Apart from an overall increasing pattern of precipitation extremes, it is noticed that the contribution of frequency dominates over intensity. Specifically, the frequency of 99th percentile daily rainfall is projected to increase approximately by two‐ (SSP245) to three‐ (SSP585) times in future. We also proposed a new zoning of entire Indian mainland, identified as six Homogeneous Precipitation Zones (HPZs). HPZ‐wise analysis reveals that the increase in frequency dominates over intensity for all the HPZs with a varying extent. For instance, increase in frequency is more for the climatologically high‐precipitation zones (HPZ‐3: Western Ghats, and HPZ‐6: North‐east India), whereas increase in intensity is more for the low‐precipitation zones (HPZ‐1: North‐west India, and HPZ‐4: Peninsular India). The degree of increase gets even more pronounced under the worst scenario SSP585, indicating a potential impact of anthropogenic activities on changing precipitation extremes. Findings of this study should be accounted in the climate change adaptation and mitigation strategies for future. Plain Language Summary: There are different characteristics of extreme precipitation, such as how frequent they occur, its intensity. Owing to change in climate, these characteristics are changing as time passes, as well as from one location to another location. How has it been changed in the past and how will it be changing in future? Is there any link with the nature of rainfall in a region? These are the focus of this study. We considered entire Indian mainland as our study domain that spans across a wide range of climatology. Overall, it is noted that both frequency and intensity are increasing and it is going to increase further in future. Moreover, frequency is increasing more rapidly than intensity. However, this finding varies from region to region. The regions that receive high precipitation, in general, may experience maximum increase in frequency (northeast and western ghats region in India), whereas the regions with relatively low precipitation may experience maximum increase in intensity (southern peninsular India). Such findings are expected to be useful in many applications related to climate change impacts on water sector. Key Points: Both frequency and intensity of extreme precipitation are increasing with spatial variation and it is going to increase further in futureIn general, change in the characteristics of precipitation extremes is dominated by increase in frequency rather than intensityHigh precipitation regions experience an increase in frequency and low precipitation regions experience an increase in intensity [ABSTRACT FROM AUTHOR]

The article presents a study that was conducted to analyse water resources availability and demand in the Mahanadi River in India under climate change conditions. The study sought to determine present water availability and demand on Mahanadi basin using distributed hydrologic model (DHM), and to project future water demand and analyze the water stress in the basin using the precipitation output of Canadian Centre for Climate Modelling and Analysis General Circulation Model (CGCM2). Model results indicate that the Mahanadi River Basin is expected to experience progressively increasing intensities of flood during September, for the period 2075-2100, and drought in April, for the period 2050-2075. The study also stresses on the need for re-defining water management policies.