Is winter monsoon rainfall over South Peninsular India increasing in global warming era?

An observational evidence of decrease in Indian summer monsoon rainfall in the recent three decades of global warming era

“…In the recent three decades, there is a decrease in north-south SST gradient which is not favorable for the active monsoon conditions over India. The earlier studies (Naidu et al, 2009(Naidu et al, , 2010 also pointed out that the rate of warming of the southern latitudes is high when compared to that of northern latitudes over the Indian Ocean.…”

Precursors of northeast monsoon rainfall variability during extreme epochs of the global warming era

“…The enhancement of northeast monsoon rainfall over SP India in the global warming period is associated with intensification of the easterly belt in the lower troposphere over the major part of the northeast monsoon region of India and the strengthening of the subtropical westerly jet over India (according to Naidu et al . ; ). In the active monsoon epoch, the highly intensified easterly wind in the lower troposphere and the subtropical westerly jet in the upper troposphere are associated with surplus rainfall.…”

“…According to Naidu et al . (; ), a weak Southern Oscillation Index, intensified lower troposphere easterlies over the major part of the northeast monsoon region, an increase in the north–south temperature gradient and the strengthening of the subtropical westerly jet over north India are responsible for the enhancement of northeast monsoon rainfall over SP India in the global warming period. Surplus rainfall in active monsoon epochs releases abundant amounts of latent heat energy into the atmospheric system.…”

Changes in the frequencies of northeast monsoon rainy days in the global warming

“…By considering the sub-divisional rainfall amounts, Naidu et al (2010) reported an increase in the northeast monsoon seasonal rainfall amounts over SP India. Further, they pointed that the rate of warming of the equatorial regions in the northeast monsoon season was greater than that of the northern latitudes in the northeast monsoon regime.…”

“…According to Naidu et al (2010), there is a significant positive trend of 0.274°c/100 yr in the actual values of Sea Surface Temperature [SST] gradient [temperature over the domain, 8°-16°N, 80°-92°E minus temperature over the domain, 16°-22°N, 80°-92°E] in the northeast monsoon season and on the decadal scale, the tendency is strengthened [0.2899°c/100 yr]. The rate of warming over the southern domain [0.0126°C/yr] is more than that of northern domain [0.0098°C/yr].…”