By Dr. Deepa Gavali, Executive Secretary, Gujarat Ecology Society, and Dr. Jitendra Gavali, Botanist, Vadodara, Gujarat, India

The year 2026 has been the hottest summers. The urban areas across India have seen temperatures hovering around 40^OC and heatwaves continues for a longer duration. The major reasons behind this are rapid urbanisation, loss of green cover and the expansion of impervious surfaces such as roads, buildings, and pavements. In this context, old trees and urban green cover have emerged as critical nature-based infrastructure that can help cities adapt to rising temperatures and improve overall climate resilience.

Old, luxuriant trees provide a range of ecosystem services that directly contribute to urban cooling. Their extensive canopies intercept solar radiation and create shade, reducing surface and ambient temperatures in streets, parks, residential neighbourhood, and public spaces. In addition to shading, trees cool the surrounding environment through evapotranspiration, a natural process in which water absorbed by roots is released into the atmosphere through leaves, thereby lowering air temperatures. Native tree like banyan, mahuva, neem, ashok, imli etc. have thick, luxuriant canopies and they remain evergreen during the summers, thereby are best for urban cooling.

Trees can lower pedestrian-level temperatures by up to 12°C through large radiation blockage and transpiration. In tropical, temperate, and continental climates, a mixed use of deciduous and evergreen trees in open urban morphology provides approximately 0.5°C more cooling than a single species approach.

There are a few examples in India where old trees are left intact within gardens and parks, e.g., Cubbon Park in Bangalore, Sayaji Garden in Vadodara, Lodhi Garden in New Delhi, and others. However, due to urban infrastructure projects like road widening, flyovers constructions, lake beautification and new urban area developmental works, the first ones to be removed are the old trees.  The Indira Avenue or Jail Road of Vadodara was once dotted with huge banyan trees on both sides. Their canopy was so dense that the road was avoided after 5.00 pm. People used to feel cool temperatures and were enjoying cycling beneath, even during hot summers. Unfortunately, this green pathway was lost in the road expansion in the early 1980s.

Urban infrastructure developers need to integrate the old trees within their designs and pave the way for climate-resilient cities. In Hawaii, huge banyan trees are an integral design element at places like the International Marketplace and the City Mall. The places around these trees are used for children’s activities.

Ecological services provided by an old tree cannot be compensated even with the plantation of saplings of same species. During the scorching summers, pedestrians, cyclists and two-wheeler riders have a tough time moving out during daytime. The citizens look desperately for tree shade and everyone tries to cramp in whatever small shade if available along the roadside. Maintaining green corridor within the city will not only keep the city microenvironment cool but it will make pleasant traffic movement. Tree shade will prevent wear and tear of roads from excessive heating. The need of the hour is to retain the existing old trees.

Disclaimer: The views expressed in this piece are those of the author/s and do not necessarily reflect the views or policies of AIDMI.