Climate Extremes

If we could still have the occurrence of a wide variety of natural weather and climate extremes, even, if there are no anthropogenic changes in a climate, given the fact that many weather and climate extremes remain to be the result of natural climate variability, while, natural decadal or multi-decadal variations in the climate provide the backdrop for anthropogenic climate changes, then, what is the physical basis on which a changing climate leading to changes in the frequency, intensity, spatial extent, duration and timing of weather and climate extremes, and in turn, resulting in unprecedented extremes results only from ‘anthropogenic changes in climate’?

Are we scientifically ‘clear and distinct’ about the exact factors that influence the observed changes and in turn, the projected changes in climate; if changes in extremes of a climate or weather variable remain no more related in a simple way ‘always’ to changes in the mean of the same variable (and given the uncertainty in the natural variability of climate; uncertainties in climate model parameters and structure; and uncertainty in the projections of future emissions)?

Suresh Kumar Govindarajan, Professor [HAG]

IIT Madras, 24-Dec-2024