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Hydrological extremes and land use are intimately connected, as land use alterations frequently exacerbate or mitigate the consequences of extreme events. Therefore, assessment and prediction of land use dynamics retain great significance in projected scenarios of hydrological extremes. This study aimed to quantify the impact of land use changes on future landslide-prone sites, flash flood vulnerable zones (FFVZs), and monsoon runoff. In this context, a Markov chain–cellular automata (MC-CA) model integrated with a multilayer perceptron–neural network (MLP-NN) model was designed to predict near-future land use/land cover changes (LULCC) using high-resolution existing land use/land cover (LULC) information. Uncorrected finer-scale Coupled Model Intercomparison Project Phase 6 (CMIP6) meteorological data sets and predicted LULC data were used to simulate daily runoff with the help of the Soil and Water Assessment Tool (SWAT). Statistical evaluation matrices were used to assess the efficacy of using uncorrected CMIP6 data sets for hydrological modeling. The methodology was evaluated for suitability in the ungauged high-altitude Ranikhola watershed. The prediction results showed that the watershed can be expected to be more susceptible to landslides and flash floods (9%). The most challenging discovery from this analysis was an anticipated 32.50% increase in average monsoon runoff from 2021 to 2032 compared to the observed period, 2015–2020. In addition, the runoff peak magnitude is projected to rise by 26.00%. Consequently, it is imperative to develop strategies and approaches for sustainable watershed management to address future challenges. [ABSTRACT FROM AUTHOR]

Building footprint datasets are valuable for a variety of uses in urban settings. For a number of urban applications, polygonal building outlines with regularised bounds are required and are extremely challenging to prepare. We propose a deep learning strategy based on convolutional neural networks for retrieving building footprints. The model was trained using images from a variety of places across the metropolis, highlighting differences in land use patterns and the built environment. The evaluation measures indicate how the accuracy characteristics of distinct built-up settings differ. The results of the model are equivalent to cutting-edge building extraction methods. [ABSTRACT FROM AUTHOR]

Rivers are vital freshwater resources that cater to the needs of society. The burgeoning population and the consequent land-use changes have altered the hydrologic regime with biophysical and chemical integrity changes. This necessitates understanding the land-use dynamics, flow dynamics, hydrologic regime, and water quality of riverine ecosystems. An assessment of the land-use dynamics in the Aghanashini River basin reveals a decline in vegetation cover from 86.06% (1973) to 50.78% (2018). The computation of eco-hydrological indices (EHI) highlights that the sub-watersheds with native vegetation had higher infiltration (and storage) than water loss due to evapotranspiration and meeting the societal demand. The computation of water quality index helped to assess the overall water quality across seasons. The study provides insights into hydrology linkages with the catchment landscape dynamics to the hydrologists and land-use managers. These insights would aid in the prudent management of river basins to address water stress issues through watershed treatment involving afforestation with native species, appropriate cropping, and soil conservation measures. [ABSTRACT FROM AUTHOR]

Buildings are considered prominent objects for understanding the pattern of growth in an urban setting. Remote sensing technology plays a vital role in facilitating data generation pertaining to various urban applications. Digital surface models represent the elevation of the earth surface features, and can be obtained from stereo images, radar, laser scanning, and so on. Photogrammetric techniques applied to optical stereo satellite images are economical and fast ways to generate height information of buildings. In this work, a quantitative and qualitative analysis of digital surface models generated from Cartosat-1 stereo images is compared with openly available data. The study finds that it is possible to acquire about 50 percent of building heights with acceptable error limits. The experimental results indicate that the quality of height information is suitable for applications to assess urban development at a macro scale, but not for individual building-level modeling. [ABSTRACT FROM AUTHOR]

Urbanisation refers to the physical growth of urban region with the increase in the population due to either migration or amalgamation of peri-urban areas into cities. India, with 31.5% (377 million) urban population as per 2011 census, has been experiencing the global trend of increasing urbanisation. Urbanisation process involves changes in land uses and enhanced consumption of energy, which contribute significantly to the global warming. This necessitates developing effective urban planning strategies with the regular monitoring of landscape dynamics. Availability of temporal data of the earth's surface acquired through space borne sensors helps in mapping and monitoring landscape. Spatial metrics aid in quantifying the urban structure and patterns of urban growth. In this context, the current research reports of urban growth (urbanization and urban sprawl) in Ahmedabad, based on the temporal land use dynamics considering four decades remote sensing data with gradient analysis and spatial metrics. Urban land use dynamics, in terms of both patterns and quantities, were studied using Shannon Entropy index and select spatial metrics for the study area with 10 km buffer (from administrative boundary). This provided insights into the pattern of urban development and its complexity. Results indicate that Ahmedabad city has rapidly grown from 3.2 % to 14.58 % in the period from 1975 to 2010. Spatial metrics highlight that the core area of the city (which is the core financial area) has grown into a compact single urban class, whereas the outskirts have dispersed urban patches. This analysis helps the regional planners and decision makers in advance visualisation of urban patterns for sustainable planning of the city with basic amenities and infrastructure. [ABSTRACT FROM AUTHOR]

Floods in an urbanized landscape refer to the partial or complete inundation from the rapid accumulation or run-off resulting in the damage to property and loss of biotic elements (including humans). Urban flooding is a consequence of increased impermeable catchments resulting in higher catchment yield in a shorter duration and flood peaks sometimes reach up to three times. Thus, flooding occurs quickly due to faster low times (in a matter of minutes). Causal factors include combinations of loss of pervious area in urbanising landscapes, inadequate drainage systems, blockade due to indiscriminate disposal of solid waste and building debris, encroachment of storm water drains, housing in floodplains and natural drainage and loss of natural flood-storages sites. Flood mitigation in urban landscape entails integrated ecological approaches combining the watershed land-use planning with the regional development planning. This includes engineering measures and flood preparedness with the understanding of ecological and hydrological functions of the landscape. Bangalore is experiencing unprecedented urbanization and sprawl in recent times due to concentrated developmental activities with impetus on industrialization for the economic development of the region. This concentrated growth has resulted in the increase in population and consequent pressure on infrastructure, natural resources and ultimately giving rise to a plethora of serious challenges such as climate change, enhanced green-house gases emissions, lack of appropriate infrastructure, traffic congestion, and lack of basic amenities (electricity, water, and sanitation) in many localities, etc. This study shows that there has been a growth of 632% in urban areas of Greater Bangalore across 38 years (1973 to 2010). Urban heat island phenomenon is evident from large number of localities with higher local temperatures. The study unravels the pattern of growth in Greater Bangalore and its implication on local climate (an increase of ~2 to 2.5 ºC during the last decade) and also on the natural resources (76% decline in vegetation cover and 79% decline in water bodies), necessitating appropriate strategies for the sustainable management. The study reveals that frequent flooding (since 2000, even during normal rainfall) in Bangalore is a consequence of the increase in impervious area with the high-density urban development in the catchment and loss of wetlands and vegetation. This is coupled with lack of drainage upgrade works with the changes in enhanced run-offs, the encroachment and filling in the floodplain on the waterways, obstruction by the sewer pipes and manholes and relevant structures, deposits of building materials and solid wastes with subsequent blockage of the system and also low restrictions from under capacity road crossings (bridge and culverts). The lack of planning and enforcement has resulted in significant narrowing of the waterways and filling in of the floodplain by illegal developments. [ABSTRACT FROM AUTHOR]

Globalisation and opening up of markets has seen large-scale unplanned urbanisation in previous decade especially in developing countries like India. Dynamic changing policies influenced by global entities to set up profitable, industry-oriented cities have powered extensive migration with population upwelling contributing to the fast-growing urban expansion that needs monitoring and planning to design urban cities of the future. Research agenda here is to understand the change in land use (LU) temporally and model the land use change based on cellular automata through slope, land use, excluded, urban, transport and hillshade (SLEUTH) approach. Scientific studies carried out to address LU, its linkage with rising surface temperature and prediction of urban growth are limited or conducted only for smaller geographical extents and lack study especially in the most active and diverse country like India. This paper proposes implementation of integrated method of LU, land surface temperature dynamics, and urban modelling for four major cities: Delhi, Mumbai, Kolkata and Hyderabad. Of the four cities, Delhi, the capital of India, has shown enormous change in terms of increasing paved surface from 21.63% in 2003 to 31.56% in 2017 with corresponding mean surface temperature surge of 25.93 °C and 36.51 °C, respectively, suggesting one of the worst affected cities. Predicted LU envisions the possibility of a spurt in unplanned growth across the city boundary that would hinder developing basic amenities and would cause increased thermal discomfort amongst residents. This was understood through analysis of land surface temperature in relation to changing land use, indicating a need for sustainable development strategies to be implemented to avoid business-as-usual scenario. The analysis aims to help planners and city managers to understand region-specific issues in urban growth and to improve the cityscape with specific interventions. [ABSTRACT FROM AUTHOR]

Energy consumption constitutes one of the important sources of carbon dioxide emission which cause global warming. This paper analyses greenhouse gas (GHG) emissions due to energy consumption in the domestic sector considering household activities and socioeconomic parameters. A stratified random survey of 1967 households in Bangalore pertaining to the energy consumption reveals that annual per capita electricity consumption ranges from 9.64 to 2337 kW h/year with an average of 336±267 kW h/year. Emission from most of the wards (66 wards) is about 10–15 Gg/year, while wards in peri-urban areas emit less than 10 Gg/year. Extrapolation of these, show that total carbon dioxide from all wards of Greater Bangalore accounts to 3350 Gg/Year. The energy consumption analyses reveal a proportional increase in the per capita energy consumption with the family income suggesting that economic levels in respective wards is an important parameter in the domestic energy consumption and also GHG emissions. Suggested interventions through large scale penetration of renewable sources of energy and energy conservation would help in reducing greenhouse gases and consequent warming of the Earth. [ABSTRACT FROM AUTHOR]