So much for settled science! With every new climate study, the science just gets more and more unsettled.
Germany’s Max Planck Institute’s latest press release is about a new paper titled:
Tracking the Evapotranspiration Cycle
Reduced evaporation from the earth’s surface despite warming of the atmosphere
to appear in Nature Journal, click here, and is titled in English: Recent decline in the global land evapotranspiration trend due to limited moisture supply
Nature, 10. October 2010; doi:10.1038/nature09396
The Max Planck Institute press release starts as follows:
The earth’s climate system is complex and is not fully understood. Up to now scientists believed that global warming would speed up evaporation and the evapotranspiration cycle. But now scientists of the Max Planck Institute for Biogeochemisty in Jena, Germany have run into a huge surprise: using 250 measuring stations distributed over the earth’s surface and satellite data, scientists have determined that the worldwide trend of increased evaporation of the earth’s land surface has weakened immensely, or has even reversed between 1998 and 2008. And this despite that the earth’s atmosphere having warmed up during this time period. One possible explanation is that the scientists found that the ground, especially in southern Africa, Australia and South America, dried up increasingly, and so less moisture could evaporate. Why the land’s surface in the southern hemisphere became drier and whether this trend will continue is still unclear (Online-Version Nature, 10. October 2010).
The scientists of the Fluxnet Initiative have estimated how much moisture rises into the atmosphere. Between 1982 and 2008, 65,000 cubic kilometers of water evaporated globally each year, That’s a water amount equal to the Caspian Sea, the world’s largest lake. According to Markus Reichstein, research group leader at the Max Planck Institute for Biogeochemisty in Jena and coordinator of the study:
For the first time our data shows how evaporation has changed during this time period.
First the amount of water evaporating from the global land area rose steadily by 120 cubic kilometers until 1997. But then the trend weakened significantly thereafter. According to Martin Jung, who evaluated the data at Max Planck Institute in Jena:
That the temperature increased slightly while the rate of increased evaporation weakened was very surprising. After all, warmer air is known to have the capability to absorb more moisture.
Climate scientists thought up to now that a warmer earth would evaporate more water. However, this appears to be limited regionally. Especially in Australia, East Africa and South America the exact opposite occurred between 1998 and 2008. There, much less water evaporated. This decrease was not able to offset the increase occurring in China and India.
The scientists believe that ground in the southern continents has become more dried out, and thus does not evaporate as much water. Jung warns explicitly against concluding that this is a clear sign of climate change: most probably it has to do with a natural fluctuation that cannot yet be explained.
Dr Reichstein says that the trend must be observed for a longer period and that ENSO cycles may play a role.
According to Nature Journal:
Whether the changing behaviour of evapotranspiration is representative of natural climate variability or reflects a more permanent reorganization of the land water cycle is a key question for earth system science.
The scientists are concerned that drier land in the southern hemisphere could lead to reduced photosynthesis, and thus more CO2 in the atmosphere, and thus more warming. But there is still a lot of scientific that needs to be done to understand what is going on.
Future measuremnts will tell us more, says Reichstein.
Conclusion: Obviously the models used up to now for predicting future climate have had no semblance to what is actually going on out in the field. They’re not even close. The scientists of the prestigious Max Planck Institute are very surprised by the findings. So much is still unknown about how the climate works.
Note: I didn’t translate the entire MPI press release, just the major parts of it. Here’s a post I wrote in July about the same topic: https://notrickszone.com/2010/07/06/max-planck-institute-report-its-back-to-the-drawing-board-for-climate-modellers-alarmist-scenarios-unrealistic/