According to this piece in the WSJ, the IPCC routinely omits the positives of Global Warming in their reports:
According to a 2004 paper by British geographer and climatologist Nigel Arnell, global warming would likely reduce the world's total number of people living in "water-stressed watersheds"—that is, areas with less than 1,000 cubic meters of water resources per capita, per year—even though many regions would see increased water shortages. Using multiple models, Mr. Arnell predicted that if temperatures rise, between 867 million and 4.5 billion people around the world could see increased "water stress" by 2085. But Mr. Arnell also found that "water stress" could decrease for between 1.7 billion and 6 billion people. Taking the average of the two ranges, that means that with global warming, nearly 2.7 billion people could see greater water shortages—but 3.85 billion could see fewer of them.
The IPCC's much-shorter "Summary for Policy Makers" is even more one-sided. It is riddled with warnings of warming-induced drought and—while acknowledging that a hotter Earth would bring "increased water availability" in some areas—warns that rising temperatures would leave "hundreds of millions of people exposed to increased water stress." Nowhere does it specify that even more people would probably have more water supplies.
VH: After reading the article, who can believe that the IPCC is even handed in its treatment of climate issues? The IPCC is essentially a mouth piece for AGW advocates.