Reference: Gerten, D., Schaphoff, S. and Lucht, W. 2007. Potential future changes in water limitations of the terrestrial biosphere. Climatic Change 80: 277-299.

Climate-alarmists typically predict increasing drought for many parts of the world as the air’s CO2 content continues to climb; and they claim that this phenomenon will have huge negative consequences for earth’s terrestrial plants. However, that seemingly simple conclusion ignores some important mitigating circumstances and feedback phenomena that suggest a significantly different outcome. After completing all of their analyses, Gerten et al.’s “main finding” was that “the final CO2 effect on LTA, an index that quantifies the degree to which transpiration and photosynthesis are co-limited by soil water shortage, is a positive one, which led them to further conclude that “LTA is a better proxy for limitation of plant growth and net primary production than soil moisture itself or precipitation.

Consequently, even in a world of declining soil moisture content - which is itself just the opposite of what is observed in the real world (see Soil (Water Status - Field Studies) in our Subject Index) - the physiological benefits provided by the ongoing rise in the air’s CO2 content tend to overpower whatever negative effects global warming might have on earth’s plant life; and this is one of the reasons why the Greening of the Earth continues unabated over the entire planet.  See full report here

There will be more flooding and less drought than has been forecast in widely used projections of global warming, according to a new study. The study using measurements taken by NASA weather satellites compared ocean rainfall from 1987 to 2006 to earlier climate model projections of what that precipitation would be. The models, based on physics equations, were found to be off the mark, according to the study released Thursday by the journal Science.

Projections have suggested that rainfall will rise in coming decades, but not as fast as temperature, leading to drier days and droughts worldwide. In February, the Intergovernmental Panel on Climate Change (IPCC) cited studies showing “extreme drought increasing from 1% of present-day land area to 30% by the end of the century.” The new study suggests models are flawed, underestimating how increased humidity in a warmer climate produces more rain clouds, Wentz said by e-mail. The new findings suggest climate modelers are overstating how much rainfall will dry up in a warmer climate, says Wentz. “With respect to severe weather events like hurricanes, I am not sure what the implications are. But this much more rain worldwide could certainly pose one of the most serious risks (from flooding) associated with climate change,” he says. See full USA TODAY story here

Hurricanes over the past 5,000 years appear to have been controlled more by El Nino and an African monsoon than warm sea surface temperatures, such as those caused by global warming, researchers said Wednesday. The study, published in the journal Nature, adds to the debate on whether seas warmed by greenhouse gas emissions lead to more hurricanes, such as those that bashed the Gulf of Mexico in 2005.

Some researchers say warmer seas appear to have contributed to more intense hurricanes, while others (like Dr. William Gray and Dr Chris Landsea in stories on Icecap) disagree. The U.N. International Panel on Climate Change said this year it was more likely than not that humans contribute to a trend of increasingly intense hurricanes.

Frequent strong hurricanes thrived in the Western Atlantic during times of weak El Ninos, or warming of surface waters of the Eastern Pacific Ocean, and strong West African monsoons even when local seas were cooler than now, the study said. “Tropical sea surface temperatures as warm as at present are apparently not a requisite condition for increased intense hurricane activity,” Jeffrey Donnelly, the lead author and researcher at the Woods Hole Oceanographic Institution, said in the study. Intense hurricanes made landfall during the latter half of the Little Ice Age, a period of cooling that occurred approximately from the 14th to mid-19th centuries, he said.  Changes in intense hurricane activity should be better predicted with more study of the Eastern Pacific and West African climate patterns, it said. See full story here.

Also see CO2 Science review of Kossin,et al. in GRL 2007 paper “A globally consistent reanalysis of hurricane variability and trends.” In the words of the five scientists who conducted the work, “using a homogeneous record, we were not able to corroborate the presence of upward trends in hurricane intensity over the past two decades in any basin other than the Atlantic,” and they say that “since the Atlantic basin accounts for less than 15% of global hurricane activity, this result poses a challenge to hypotheses that directly relate globally increasing tropical sea surface temperatures to increases in long-term mean global hurricane intensity.” See full story here.

Heavy snow is forecast this weekend in Wyoming, snow and ice mar Victoria Day holiday weekend in Timmins, Canada while heavy snows bury northwest China. In the Southern hemisphere, an early Australian snowstorm delights skiers and record cold is reported with some casualties in South Africa including first snow in Georgetown in 33 years.

Update (5/28/07):  In Calgary, Alberta in Canada a late snow downed power lins and trees while a late snow hits North Dakota. Also it is so cold in Britain that snow may fall in east Anglia and Scotland.

Update (5/29/07) Two dead in french snowstorms, spring snow creates havic in Switzerland, freak snowstorm hits Nepal, cold prompts record demand for energy in Argentina .

Update (5/30/07) from an Icecap member in Brazil, Eugenio Hackbart of MetSul Meteorologia Weather Center, one of the most important private weather organizations in Latin America, comes word that snow fell in the higher elevation of Southern Brazil over this past week and that next week could be even colder with low temperatures not seen in that part of the globe during the month of May in the last 20 to 30 years.  South America is under a sequence of cold blasts not seen since the very cold climatic winter of 2000 (La Niña), Eugenio reported.

Update: (6/1/07) Argentinian cold wave in which the country was beset by the coldest May since 1962 led to electricity and natural gas shortages this week, idling factories and taxis and causing sporadic blackouts in the capital.

Climate Science has selected two errors in Chapter 1 of the 2007 WG1 IPCC Report to highlight in this weblog.

(1) “This is the so-called butterfly effect: a butterfly flapping its wings (or some other small phenomenon) in one place can, in principle, alter the subsequent weather pattern in a distant place. At the core of this effect is chaos theory, which deals with how small changes in certain variables can cause apparent randomness in complex systems.” [page 105]

(2) The second error (and it is a big one) is their unsubstantiated claim that “Projecting changes in climate due to changes in greenhouse gases 50 years from now is a very different and much more easily solved problem than forecasting weather patterns just weeks from now. To put it another way, long-term variations brought about by changes in the composition of the atmosphere are much more predictable than individual weather events.” [from page 105]

This is a remarkable claim, and forms the basis of the entire IPCC concept. This is such an absurd, scientifically unsupported claim, that the media and any scientists who swallow this conclusion are either blind to the scientific understanding of the climate system, or have other motives to promote the IPCC viewpoint. The absurdity of the IPCC claim should be obvious to anyone with common sense.  See in his blog post and links within to earlier blogposts why these two assumptions are blatantly in error.

UPDATE: Roger followed this up with the following blog on why Climate Prediction is More Difficult than Weather Prediction and check out American Thinker’s coverage of Roger’s blogs on the climate models here