The Aravalis , one of the oldest ranges which start in Gujarat, pass through Rajasthan and Haryana and terminate in Delhi, cover a length of around 682 kilometres and act as a green barrier between the Thar desert and the Gangetic plains of India. The mountain range has always been a source of water and minerals.There has been a considerable decrease in green cover in the Aravalis in the recent times, which can most importantly be attributed to construction activities that are rampant in the region. Other causes are anthropogenic activities such as unplanned mining, overgrazing, extraction of fodders and other forest resources by growing inhabited human population, various tourism activities and shortfall of proper forest management.A Forest Survey of India report reveals a significant decrease in forest cover and density of Sariska National Park located in the Aravalis over the years. In Delhi too, the remnants of Aravalis which are called the Ridge are receding every year. The State Forest Report in 2017 revealed that both “very dense forest” cover and “medium dense forest” have reduced by more than 1 sq km in the past two years in Delhi. The report says that Delhi’s addition of green area is mostly through open forest cover achieved because of plantation and conservation activities, while decrease in dense forest cover has been attributed to civil construction.An increasing trend of ambient temperatures is one of the most visible climate change-related impacts in the Aravali region. There is an unprecedented exploitation of land in the northern Aravali range around the Delhi-Gurugram region, which extends further with industrial growth of places like Manesar, Bhiwadi, Alwar and other areas in the NCR, for constructing new buildings and expanding the urban area. This urbanisation process increases temperature owing to changes in land surface characteristics, resulting from increased pavings, rooftops, buildings and other urban infrastructures. Especially, night-time temperatures are greatly influenced by urbanisation. The built-up areas in cities experience higher temperatures than green, open or other non-urban areas. This phenomenon, which is also called urban heat island effect, is intensifying as more regions of the Aravalis are being converted into concrete towns. The Intergovernmental Panel on Climate Change’s (IPCC) fifth assessment report highlighted that such changes could lead to an increase of 2-4° C in ambient temperatures in cities and expanding urban areas.Delhi and nearby cities are also hit by the loss of natural Aravalis. The major urban areas around Aravali range viz., Jaipur, Alwar, Delhi and Gurugram have reported an increase in temperatures in the recent years. Studies have shown that due to urban heat island effect in Delhi, dense built-up areas have been experiencing overall 2-5°C higher temperature than green areas, especially during night. This rise in temperatures in the cities leads to increased energy demands owing to air-conditioning and refrigeration, and resulting in heat generation from vehicular traffic, air-conditioners, refrigerators, industries etc.This is likely to further aggravate the cities’ cooling energy demand. The rampant urbanisation is expected to exacerbate the climate-change impacts on rainfall, heat stress and other weather events by modifying the local climate.Warmer climate and construction activities have also led to loss of precious water resources. Various water bodies in the Aravalis — Ajabgarh lake, Pankot lake, Dumduma lake, Jaisamand lake, Kotla lake in Mewat district, smaller ponds and water bodies in Asola wild life sanctuary — have either completely depleted or have been encroached upon. Moreover, a report by the state’s agriculture department shows that the groundwater has depleted by almost 8 metres in various districts of Haryana surrounding Delhi in last 40 years.Aravalis have long been touted as lungs for NCR, and by degrading them we are leading the human population of the region to suffocation.(The author is professor, Centre for Atmospheric Sciences, India Institute of Technology, New Delhi)

Stay updated with all the Latest Gurgaon headlines here. For more exclusive & live news updates from all around India, stay connected with NYOOOZ.