Just One Problem With This Week's IPCC Report - Probably Too Optimistic - Der Spiegel

[hatrack]

EDIT

And more recent reports, which were not mentioned in the Synthesis Report, mean that the picture the IPCC paints may in fact be too rosy:


The global CO2 emissions from the burning of fossil fuels are increasing faster than ever. Since 2000 they are averaging a growth of more than 3 ppm (parts per million) a year. In previous decades the average was only 1.3 ppm. "Recent emissions seem to be near the high end of the fossil fuel use scenarios used by the Intergovernmental Panel on Climate Change (IPCC)," says Michael Raupach, the Australian physicist and leader of the Global Carbon Project.


Around half of the anthropogenous CO2 emissions don't remain in the earth's atmosphere and are absorbed by the oceans and by plants. But these natural carbon reducers may have been overestimated. The forests of the mid-range and high northern latitudes probably absorb 40 percent less carbon dioxide than climate change calculations estimate, according to a multinational study recently published in Science magazine. Kevin Gurney, climate researcher at Purdue University in West Lafayette in the US, said it was wrong to assume that the biosphere will somehow come to the rescue. Trees can't absorb that much additional CO2, he said.


Scientists are also taking a more cautious view of how much help the world's oceans can provide. Current measurements show that the North Sea's capacity to absorb CO2 is already declining. Belgian, Dutch, Canadian and US researchers referred to a "rapid decline in CO2 buffer capacity" in the Global Biogeochemical Cycles magazine. Other studies see a similar development in the entire North Atlantic.


There is a steady decline in sea ice in the Artic Ocean each summer. At the beginning of October the National Snow and Ice Data Center (NSIDC) reported a new record low for 2007. The entire ice surface amounted to just 4.3 million square kilometers -- 23 percent down from 2005, the previous record season. The legendary Northwest Passage was found to be free of Arctic ice. The NSIDC researchers now expect the Arctic to be free of ice during the summer from 2030 onwards -- decades earlier than forecast in the climate projections referred to the new IPCC report which foresees ice-free Arctic summers in the latter part of the 21st century.

EDIT

http://www.spiegel.de/international/world/0,1518,518231,00.html