Interesting paper but the headlines it generates are even more interesting.
Recent decline in the global land evapotranspiration trend due to limited moisture supply
Martin Jung et al, Nature, DOI:10.1038/nature09396
The authors write:
Our results suggest that global annual evapotranspiration increased on average by 7.1 ± 1.0 millimetres per year per decade from 1982 to 1997. After that, coincident with the last major El Niño event in 1998, the global evapotranspiration increase seems to have ceased until 2008. This change was driven primarily by moisture limitation in the Southern Hemisphere, particularly Africa and Australia.
But the New Scientist in its wisdom reports this under the headline:
Water cycle goes bust as the world gets warmer
That evapotranspiration should decrease if the moisture is not there in the first place seems perfectly reasonable. That we will have to use technology to get ground water levels back up as water usage increases is also fairly obvious.
It occurs to me that global temperatures have been stable if not declining over the last decade which also fits the period when they measured the stable evapotranspiration.
I note – in passing – that evaporation from ocean surfaces is some 7 times greater than the evaporation from land surfaces while precipitation over the oceans is about 4 times greater than that over land.
But the NS headline is a little bizarre.
The k2p blog 