Earlier today1, the United Nations Intergovernmental Panel on Climate Change (IPCC) released the Synthesis Report from its fourth assessment. The Synthesis Report pulls together results from the first three reports (The Physical Science Basis; Impacts, Adaptation, and Vulnerability; and Mitigation of Climate Change). “It provides an integrated view of climate change as the final part of the IPCCs Fourth Assessment Report.” The “Summary for Policymakers” is available from the IPCC website.2 Here are a few points that I find particularly striking.2
Changes in temperature, sea level, and northern hemispere snow cover relative to the average for 1961-1990.I knew about the pattern in global temperatures – roughly a 2°F increase since 1850, most of it in the last half century – but the rise in global sea level is much greater than I thought – roughly 8 inches since 1870. Eight inches may not sound like much, but ask someone who has coastal property on a nice, sandy beach how much difference eight inches could make.
Comparison of observed climate change with model projections including anthropogenic forcings (pink) and with natural forcings only (blue).It takes a lot of heavy duty math, physics, and computer modeling to produce the climate models used to produce the figure to the left, but it doesn't take any to see that the observed average temperature (the thin black line) falls nicely inside the model projections that include anthropogenic forcings. The figure not only shows why the IPCC concluded that human activities are responsible for most global warming in the last half-century, it also shows that the models they use to project climate change into the next century work very well.
Projections for global average temperature over the next century under various emissions scenarios.The pink line in this figure corresponds to holding greenhouse gas levels in the atmosphere at year 2000 levels. That obviously won't happen. The IPCC included it to provide a baseline for comparison. None of the scenarios illustrated here include climate policies. They illustrate what is likely to happen if we do nothing. The lowest end of the plausible range among all scenarios is for global average temperature to be about 2.5°F higher than its 1980-1999 average. The highest end is about 11.5°F. The range of best estimates for the six scenarios is 3.5-7.0°F.
Projected world surface temperatures for the end of the 21st century.- it is very likely we'll see increases in the frequency of heat waves and heavy precipitation,
- it is likely we'll see more tropical cyclones, i.e., hurricanes, and
- there is high confidence that many arid and semi-arid areas will have fewer water resources than they do now.
I'll quote a few more points verbatim without comment:
- Anthropogenic warming could lead to some impacts that are abrupt or irreversible, depending upon the rate and magnitude of the climate change.
- There is high confidence that neither adaptation nor mitigation alone can avoid all climate change impacts; however, they can complement each other and together can significantly reduce the risks of climate change.
- Delayed emission reductions significantly constrain the opportunities to achieve lower stabilisation levels and increase the risk of more severe climate change impacts.
- There is high agreement and much evidence that all stabilisation levels assessed can be achieved by deployment of a portfolio of technologies that are either currently available or expected to be commercialised in coming decades, assuming appropriate and effective incentives are in place for their development, acquisition, deployment and diffusion and addressing related barriers.
111:00am in Valencia.
2Since downloads from the IPCC site seem to be pretty small, a copy of the “Summary for Policymakers” is also available here.
3All of the quotes are direct from the “Summary for Policymakers.”
It's interesting how the IPCC 2007 graphs don't show any data after 1998 !!!
This data is readily avaliable from the IPCC's own Working Party No1, The Hadley Centre. The Hadley Centre claimed "recent falling temperatures are misleading" ... and it implemented a rolling 11 year average ... which has also now turned downwards !!!!
The falling temperatures of the past decade don't support the IPCC political agenda.
"Global warming" is the greatest scam the world has ever seen.
Huh? Look at that top graph again. It's Figure SPM.1 (from the Summary for Policy Makers). The data goes through 2005, and the trend is clearly up, not level or down. Quouting from the Summary for Policy Makers:
Doesn't sound like a cooling world to me.