In both cases there were serious droughts and I've heard that in China it was a terrible flood year for the Yangtze but I haven't looked in to it in detail.

And during those famines the overall life expectancy was still higher than the pre-revolution non-famine life expectancy (from birth, mind. I don't know how you would find, say, age 8+ life expectancy which would be perhaps a more useful metric in some ways)

These were the last famines in each of these regions, both of which had suffered famines for centuries

You can read more on this and famines in other countries under capitalist colonial domination in the book Late Victorian Holocausts. Untold millions died before and after the year 1900 as the brits abolished "inefficient" community grain stores and El Nino droughts destroyed lands that had been fertile for decades, while blind private market ideology kept any food aid from being disbursed so as to keep the "natural" price of rice and grain from being disrupted. Food was exported to the imperial core while millions starved.

All famines have some parameterization you can apply of how much fault was due to political decisions versus extraneous factors like climate. This is something that will be endlessly debated according to peoples' own particular beliefs.