Modelling archetypes of heat adaptation strategies to prevent maladaptation of Indian cities to climate changes

Indian cities have been experiencing rapid urbanisation over the past years that led to uncontrolled urban expansions and surges of informal settlements. Recent extreme heat events -- like the 2024 Indian heatwaves with temperatures above 50°C -- have importantly affected urban populations, particularly in informal settlements, and led to important heat-related mortality epidemics.  

To inform future urban planning, urban climate modelling can be used to estimate the potential impact of different urban heat adaptation strategies on local urban climates. Nevertheless, running urban climate models for real-case scenarios over large cities and for multiple adaptation scenarios comes at a great cost. Urban climate data scarcity in India also prevents prior model evaluation to support the evidence provided by model outputs. Therefore, we design a set of idealised simulations that use the Weather Research Forecast (WRF) model with its Building Effect Parameterization and Building Energy Model (BEP-BEM) urban climate model activated (BEP-BEM) to estimate which adaptation strategies are expected to have the greatest impacts on heat reduction. Our simulations are run for extreme hot inland and coastal tropical days characteristic of two major Indian cities: Jodhpur (Rajasthan), and Bhubaneshwar (Odisha).

By relying on the definition of archetypes of urban forms affected by typical urban adaptation strategies (e.g., street level greening) we aim at providing a useful understanding of how each adaptative strategy starts becoming interesting for heat mitigation in the two climate contexts of Jodhpur and Bhubaneshwar. The use of archetypes of urban forms allows our results to be transferrable to other cities in similar climate contexts potentializing future decision making in similar cities. It also allows us to revise our knowledge on the expected impact of typical adaptation strategies (e.g., street ventilation, cool roofs, urban greening, urban watering…) in tropical inland and coastal climates through simple and easily understood urban climate models.