Just 2% short of the magic 97% number, I’m sure the SkS kidz will be devastated.
From Reuters:
Drafts seen by Reuters of the study by the U.N. panel of experts, due to be published next month, say it is at least 95 percent likely that human activities – chiefly the burning of fossil fuels – are the main cause of warming since the 1950s.
That is up from at least 90 percent in the last report in 2007, 66 percent in 2001, and just over 50 in 1995, steadily squeezing out the arguments by a small minority of scientists that natural variations in the climate might be to blame.
That shifts the debate onto the extent of temperature rises and the likely impacts, from manageable to catastrophic. Governments have agreed to work out an international deal by the end of 2015 to rein in rising emissions.
“We have got quite a bit more certain that climate change … is largely manmade,” said Reto Knutti, a professor at the Swiss Federal Institute of Technology in Zurich. “We’re less certain than many would hope about the local impacts.”
…
WARMING SLOWING
The panel will try to explain why global temperatures, while still increasing, have risen more slowly since about 1998 even though greenhouse gas concentrations have hit repeated record highs in that time, led by industrial emissions by China and other emerging nations.
An IPCC draft says there is “medium confidence” that the slowing of the rise is “due in roughly equal measure” to natural variations in the weather and to other factors affecting energy reaching the Earth’s surface.
Scientists believe causes could include: greater-than-expected quantities of ash from volcanoes, which dims sunlight; a decline in heat from the sun during a current 11-year solar cycle; more heat being absorbed by the deep oceans; or the possibility that the climate may be less sensitive than expected to a build-up of carbon dioxide.
“It might be down to minor contributions that all add up,” said Gabriele Hegerl, a professor at Edinburgh University. Or maybe, scientists say, the latest decade is just a blip.
In scientific parlance, I’d call that a SWAG>
At DNAindia:
Drafts seen by Reuters of the study by the UN panel of experts, due to be published next month, say it is at least 95 percent likely that human activities – chiefly the burning of fossil fuels – are the main cause of warming since the 1950s. That is up from at least 90 percent in the last report in 2007, 66 percent in 2001, and just over 50 in 1995, steadily squeezing out the arguments by a small minority of scientists that natural variations in the climate might be to blame.
That “squeeze out” is about right, look at Dr. Roger Pielke’s minority view with the AGU:
His minority view was one of 15 people that made the statement.
That works out to about a 7% minority view (or 93% majority) on that panel
Tom Nelson wonders about the 95% certainty:
[Were those numbers calculated, or just pulled out of some orifice?]
UPDATE:
Kurt Rohlfs writes via email about that statement from Tom Nelson:
Your article asks “Were those numbers calculated, or just pulled out of some orifice?” They were not calculated, at least if the same procedure from the fourth assessment report was used. In that prior climate assessment, buried in a footnote in the Summary for Policymakers, the IPCC admitted that the reported 90% confidence interval was simply based on “expert judgment” i.e. conjecture. This, of course begs the question as to how any human being can have “expertise” in attributing temperature trends to human causes when there is no scientific instrument or procedure capable of verifying the expert attributions.
Meanwhile, they haven’t offered up an explanation as to why reality and IPCC models diverge, perhaps because they can’t.
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As with sports participants, confidence/certainty levels will soon exceed 100%.
Mark my words; I am 110% sure of this.
The IPCC cannot have any degree of certainty in view of the lack of a statistical population underlying its climate models.
I know this is an old thread but I saw a slightly different quote for the IPCC leak.
“It is extremely likely that human influence on climate caused more than half of the observed increase in global average surface temperature from 1951 to 2010”
Instead of “main” they use “more than half”. Actually, the two are about the same but using the word “main” obfuscates an actually number. Once we see the true meaning it is clear that this is a huge step down from AR4. More than half could be 50.00001%. When a scientist uses a number like 50% that is usually the top end of the estimate. It means the data does NOT support any higher value.
In AR4 the attribution for man-made warming was 93% and they were 90% confident.
In AR5 the attribution for man-made warming is 50% and they are 95% confident.
In scientific terms they just admitted that while they are very confident they know what caused a little over 50% of the warming they have no idea what caused the rest. The science only supports confidence in half the total warming.
If we look at any data set we might see anywhere from .4 – .6C of warming over the 60 years used. If only half of that is man made that is only .3C at most. That is a paltry .05C/decade. It will take 200 years to reach just 1C of warming. In other words, there is no basis for any alarmism.