Aravali Mountains Impact Prediction

What this research found

The Aravali range stands between the Thar Desert and India's Delhi National Capital Region, and a 2025 policy change that limits legal protection to hills rising more than 100 metres above the surrounding terrain leaves 91% of it unguarded. Twenty-five years of climate records were used to fit baseline trends for temperature, fine particulate matter (PM2.5) and groundwater depth, and four degradation scenarios were then projected forward to 2050. Under the combined worst case, annual mean temperature runs 4.5°C above the business-as-usual path, PM2.5 reaches about 213 micrograms per cubic metre, and groundwater falls to roughly 5,055 feet.

• Even with no further degradation, the baseline trend has the region warming 1.3°C, PM2.5 rising 14 micrograms per cubic metre to about 82, and groundwater dropping another 665 feet to about 2,185 feet between 2025 and 2050.
• Mining is the most damaging single scenario modelled. Removing an estimated 500 square kilometres of hills adds 3.5°C of warming, 87 micrograms per cubic metre of PM2.5, and 1,880 feet of groundwater depletion above baseline, against 1.5°C, 20 micrograms and 287 feet for the infrastructure corridor scenario.
• The combined worst case reaches an annual mean of about 32.3°C and PM2.5 of about 213 micrograms per cubic metre, 43 times the World Health Organization annual guideline of 5, with groundwater at about 5,055 feet — a depth the study characterises as effective aquifer collapse for the region's 50-plus million inhabitants.
• The loss is already measurable: 8% of Aravali hills, some 5,773 square kilometres, disappeared between 1975 and 2019, and Haryana's forest department attributes 70% of land degradation in the range to illegal mining and deforestation. Mahendergarh district already draws water from 1,500 to 2,000 feet.
• Deprotection is documented rather than hypothetical. Notifications under the Punjab Land Preservation Act lapsed across 36 villages covering 16,930 acres in Gurugram alone, an 88% lapse rate, alongside the 100-metre threshold that removes most of the range from statutory safeguards.

How it was done

Daily temperature and PM2.5 records for the Aravali region at 28°N, 76°E were taken from the Open-Meteo historical weather archive for 2000 to 2024 and aggregated to annual means. Groundwater has no continuous monitoring record there, so a representative series was synthesised from documented regional depletion rates, anchored at 800 feet in 2000 and calibrated to observed 2024–2025 depths of 1,500 to 2,000 feet. Linear regressions on year produced business-as-usual trajectories to 2050, fitting the historical series closely for groundwater (R² = 0.99) and temperature (R² = 0.81) and less well for PM2.5 (R² = 0.62). Four scenarios — policy deprotection with urbanisation, intensive mining, infrastructure fragmentation, and all three together — were each defined from documented 2019–2025 policy changes and projects, then applied as literature-derived modifiers such as 0.4–0.5°C of warming per 10% forest loss and 50–80 micrograms per cubic metre of mining dust. The result is a 36-page paper with 41 citations and comparative trajectory plots.

Data sources

• Open-Meteo Historical Weather API — daily temperature and PM2.5 at 28°N, 76°E, 2000–2024
• Synthetic groundwater depth series calibrated to Haryana State Groundwater Board reports and field surveys
• Haryana Forest Department (2023) land degradation figures for the Aravali range
• Punjab Land Preservation Act notification records for Gurugram district
• 41 peer-reviewed sources on Aravali ecology, urban heat islands, mining dust and aquifer recovery, largely 2022–2025