Nicholas Stern: 'I got it wrong on climate change – it's far, far worse'

[Nederland]

89. You need to get up to date

Climate change is now predicted to cause an increase in weather extremes: more precipitation in some areas, droughts in others. I'd have thought that as a scientifically inclined sort, the recent crop-affecting droughts in the US, China, SE Asia, Russia and Australia might be giving you pause.

As the most recent IPCC draft shows an almost complete reversal from AR4 on trends in drought, hurricanes, floods:


IPCC AR5 Draft: “we have high confidence that natural variability dominates any AGW influence in observed/historical TC records”

Draft IPCC Ch2 bottom line on extremes: “generally low confidence that there have been discernable changes over the observed record” on lack of trends in extremes, exceptions are trends seen in temperature extremes and regional precipitation (but not floods)

On XTCs “unlike in AR4, it is assessed here..there is low confidence of regional changes in the intensity of extreme extratropical cyclones”

Bottom line IPCC trop cyclones same as SREX: “low confidence that any reported long term increases in tropical cyclone activity are robust”

More IPCC draft Ch2 on trop cyclones: “current datasets indicate no significant observed trends in global tropical cyclone frequency”

IPCC on trop cyclones “AR4 assessment needs to be somewhat revised with respect to the confidence levels associated with observed trends”

IPCC draft Ch2 on drought: “The current assessment does not support the AR4 conclusions regarding global increasing trends in droughts”

More IPCC Ch2: “low confidence regarding the sign of trend in the magnitude and/or frequency of floods on a global scale”

More IPCC draft report: Ch2: “there is currently no clear and widespread evidence for observed changes in flooding” except timing of snowmelt