Chennai rains seen reducing 6.398 mm per year in next three decades

New Delhi: Recent scientific studies have projected a decrease in annual rainfall for Chennai at the rate of 6.398 mm/year during the next three decades (2020-2050), which in turn, will affect the coastal aquifers, the Parliament was informed on Wednesday.

"However, these results are based on projections using a single regional climate model and there are large uncertainties in projecting rainfall changes at regional/local scales," Earth Sciences Jitendra Singh Minister told the Lok Sabha in a written reply.

The reduction in the projected rainfall would lead to reducing the recharge of the coastal aquifers and in addition to this, increased extraction of groundwater will also affect the coastal aquifers, he said.

As per the 6th Assessment Report (AR6) of the Intergovernmental Panel on Climate Change (IPCC), relative to 1995-2014, the global mean sea level is expected to rise by 0.28-0.55 m under the very low greenhouse emission scenario (SSP1-1.9), 0.44-0.76 m under the intermediate emission scenario (SSP2-4.5) and 0.98-1.88 m under the very high emission scenario (SSP5-8.5) by 2100.

"However, the regional sea level change can differ significantly from the global mean. The regional sea level rise estimates for the Chennai coast and its impact on freshwater aquifers have not yet been studied," the Minister added.