Urban heatwave vulnerability assessment and ecological evaluation of land use/land cover in Karachi, Pakistan: A developing megacity perspective

ABSTRACT With the consequence of global climate change, the occurrence and intensity of heatwaves have increased. Karachi has suffered severe heatwaves. It ranks top among urban localities of the world with highest UHI phenomenon in summer, proving that heat waves have strong and critical consequences on the morbidity and mortality of the Karachi population. The primary goal of this study is to develop a vulnerability-based risk assessment for areas likely to be affected by heatwaves in Karachi, Pakistan. This study indicates the relationship of Heatwave occurrences and LULC in Karachi for the period 2000 and 2022. AHP based Heatwave vulnerability matrix is prepared using composite indicators of exposure and susceptibility. Multi criteria modeling has been used for assigning weights and performing heatwave risk assessment. Its first cohort longitudinal study to be conducted in Pakistan for heat stroke surveillance vulnerability assessment framework to heatwaves based on geospatial and social integrated approach as a case study of Urban and Peri urban areas in Karachi Pakistan. The core urban areas of the city are at an extremely high risk of heatwave impacts. Given the concerning UTFVI values and the increased risk of heatwaves, immediate mitigation efforts are needed by the relevant authorities. Areas identified in this study as vulnerable to heatwaves should be prioritized for mitigation strategies against heat-related hazards. The Karachi development Authority, KDA should use the research as planning and policy making tool in order to save the Urban population from future heat hazards. Zoning practices should be implemented to improve the quality of life and health within the urban environment. • Karachi has experienced up to 34 heatwaves from 2000 to 2022. • Core urban areas are at a very high risk of being affected by heatwaves. • Urban areas of Karachi having extremely poor environmental health followed by extreme UTFVI values with high UHI exposures. • This exponential 1.5 Celsius increase in LST is very critical because in terms of percentage it accounts for approximately > 8 % of temperature gradient specially in Urban areas.