Ahmedabad : Despite receiving the majority of its annual rainfall, approximately 821.3mm, during the monsoon season, the city of Gandhinagar is now facing climate concerns due to recent unpredictable rainfall patterns.
Although there hasn’t been a significant decrease in overall rainfall between 1991 and 2022, researchers from the School of Environment and Climate Change at the Central University of Gujarat (CUG) warn of an increasing threat of extreme rainfall throughout the district.
According to the study conducted by Sandeep Kalyan and Bhawana Pathak of CUG, there has been a slight increase in rainfall during other seasons such as post-monsoon, pre-monsoon, and winter, aligning with national trends.
Interestingly, the decade from 2001 to 2010 witnessed an average monsoon rainfall of 220.15mm, surpassing the long-term average of 199.09mm.
From 2011 to 2020, there was a downward trend. Analysis of different seasons showed increasing trends in post-monsoon, pre-monsoon, and winter, but these trends were not statistically significant. The study indicates that local factors like wind patterns and Urban Heat Island (UHI) effects have a greater influence on rainfall extremes compared to global phenomena such as El Nino-Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO).
Furthermore, the study highlights a decrease in the number of no rain days and consecutive dry days (CDD), with rainfall now occurring more moderately, typically at a minimum of 10mm, but with an increase in the frequency of wet days. The occurrence of heavy rainfall, defined as 30mm, reached extreme levels in 2005, resulting in urban floods.
In recent years, certain areas in north Gandhinagar have experienced reduced moderate rainfall, specifically less than 10mm. The study suggests that this may be due to the absence of extreme heatwaves in those regions.