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By Richard Black
Environment correspondent, BBC News website, Paris


Climatic changes seen around the world are "very likely" to have a human cause, the Intergovernmental Panel on Climate Change (IPCC) will conclude.

By "very likely", the IPCC means greater than 90% probability.
The scientific body is finalising its positions on some key issues, notably forecasts of sea level rise, as it prepares to publish a major report.
But a new study released on the eve of publication suggests its previous reports may have been too conservative.

There is no doubt that for this period, the climate has been changing faster than the IPCC predicted - Stefan Rahmstorf


Research by an international group of scientists concludes that temperatures and sea levels have been rising at or above the maximum rates proposed during the last IPCC report in 2001.
The first part of its 2007 report will be formally released on Friday morning in Paris.

Strong language

Some of the language which the agency has agreed it will use to assess humanity's influence on climatic change this time is stronger than it has used previously.
In 2001, it was "likely" that human activities lay behind the trends observed at various parts of the planet; "likely" in IPCC terminology means "between 66% and 90%".
Now, the agency concludes, it is at least 90% certain that human emissions of greenhouse gases rather than natural variations are warming the planet's surface.
Scientists are unsure how much weight to give melting glaciers

"This report closes the doors to those who were able to detract from the issue, and puts an end to the notion of uncertainty and doubt about man's role in climate change," commented United Nations Environment Programme executive director Achim Steiner.
On key scientific questions - how much the Earth's surface will warm by, and how high sea levels will rise - the experts are still locked in discussion.
It is widely believed they will predict an average global temperature rise by the end of the century of between about 2C and 4.5C, without ruling out higher numbers completely.
On sea level, there is a more fundamental debate. Computer models of climate do not generally include water coming into the oceans as icecaps melt; so should the IPCC exclude this from its calculations, or estimate the effect of a process which scientists do not understand well, but which could have a big impact?
There is likely to be some backing to a theory which has proved highly controversial in recent years, with the IPCC set to conclude that it is likely - meaning a greater probability than 66% - that rising temperatures have contributed to more powerful tropical storms in some areas of the world.

At variance

As discussions entered their final phase, the journal Science published a study comparing the IPCC's 2001 projections on temperature and sea level change report with what has actually happened.
IPCC models start from the year 1990, so that gives 16 years of data to compare.
The models had forecast a temperature rise between about 0.15C and 0.35C over this period. The actual rise of 0.33C is very close to the top of the IPCC's range.

A more dramatic picture emerges from the sea level comparison.
The actual average level, measured by tide gauges and satellites, has risen faster than the IPCC predicted it would due to simple thermal expansion of seawater, and at the maximum which the scientific body considered possible if its estimates for the melting of land-based glaciers and ice sheets was included.
"Our intention with this study was to demonstrate how temperatures and sea levels have actually gone up," said study leader Stefan Rahmstorf from the Potsdam Institute for Climate Impact Research in Germany, "because 'climate sceptics' have cast doubt on IPCC projections and whether they are exaggerated."
The group suggests that if anything, the IPCC has been conservative.
-The most obvious cause of the discrepancy - a faster-than expected rise in carbon dioxide concentrations - is ruled out, as the observed CO2 rise has mimicked model projections fairly well.
Another explanation could be that the effect on temperature of increasing carbon dioxide levels in the atmosphere - the factor called "climate sensitivity" - is higher than scientists had believed when they built their computer models.
Alternatively it could be natural climate variability.
"We cannot conclude the exact cause," commented Professor Rahmstorf, "but there is no doubt that for this period, the climate has been changing faster than the IPCC predicted."
Together with his co-researchers on this project, Professor Rahmstorf is in Paris for the IPCC discussions, which will on Friday morning end with the release of summary conclusions on the current state of climate science, drawing on the work of thousands of researchers.
The full climate science report will be released later in the year, as will other IPCC chapters looking at the probable impacts of climate change, options for adapting to those impacts, and possible routes to reducing emissions of greenhouse gases.

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what about the warming spell on mars that strangely seems to conicide with the one on earth and is melting the martian ice cap? is that man made too? or could it be a simple solar cycle that has been going on for thousands of years?

is it occurring at the same rate? with the same atmosphere around earth? I know the answer to one of those questions.

The point of global warming activists (at least the ones worth talking about) isn't that there aren't causes outside of humanity. It's that humanity is eroding earth's natural "buffers" that help stabilize the effects.

sorry, not buying into the religion of environmental catastrophe...forecasters cant get teh 1 week forecast right, let alone 50 years...

just like we had the global cooling scare in the 70's, the acid rain scare in the 80's, the nuclear winter scare, ad nauseum..crap science used to scare money out of people and tax payers for scientists and environmental groups to feed their agenda, and excuses for the fascist minded political groups to try to force people to live the way they (the fascists) want, claiming they know better than anyone else how everyone else should live...and anyone who disagrees is some <insert lable here> and should be fined, imprisoned, kicked out ouf their jobs (as some want to do to scientists who call BS on man-made global warming).

Quote from Lurker3 : sorry, not buying into the religion of environmental catastrophe...forecasters cant get teh 1 week forecast right, let alone 50 years... just like we had the global cooling scare in the 70's, the acid rain scare in the 80's, the nuclear winter scare, ad nauseum..crap science used to scare money out of people and tax payers for scientists and environmental groups to feed their agenda, and excuses for the fascist minded political groups to try to force people to live the way they (the fascists) want, claiming they know better than anyone else how everyone else should live...and anyone who disagrees is some and should be fined, imprisoned, kicked out ouf their jobs (as some want to do to scientists who call BS on man-made global warming).

Predicting the weather in a week has nothing to do with predicting global warming. It's like predicting the performance of a stock portfolio: over the long term, it'll go up, but in a week or two, who knows?

What came out of the acid rain scare? Control over pollutants. What came out of the nuclear winter discussion? Disarmament treaties (though I think we're leaving the realm of science here...). Science knows what the effects of certain situations can be, whether that's molecules bonding into acid rain or erosion of the ozone layer causing the increase in certain EM wavelengths. The question is measuring if the conditions are ripe for the situation. Here's where denial, cynicism, politics, and an ungodly number of other factors tend to cloud up the situation.

Quote from Xnarg : By the Seventies, when global temperatures began to dip, many eminent scientists warned us that we faced a new Ice Age.

Really? Wrong, as mentioned many times prior.

Quote from xnarg : Over the past half-century, we have become used to planetary scares. In the late Sixties, we were told of a population explosion that would lead to global starvation.

We ARE overpopulated, and there are plenty of starving people.

Quote : Then, a little later, we were warned the world was running out of natural resources.

We are.

Quote from bonkman : Really? Wrong, as mentioned many times prior.

I agree.

Quote from bonkman : We ARE overpopulated, and there are plenty of starving people.

Ah, starvation began just recently. There was no starvation before we had so many people?

Quote from bonkman : We ARE overpopulated, and there are plenty of starving people.

Quote from Xnarg : I agree.Ah, starvation began just recently. There was no starvation before we had so many people?

I am selling 'carbon food credits' if anyone wants to buy some. Basically you give me $5 for every extra ounce of food you eat and I will make sure part of that money is used to supply food to someone who needs it. That way one can still be wasteful with food but feel good about what they are doing for the public.

Quote from Hurricane : I am selling 'carbon food credits' if anyone wants to buy some. Basically you give me $5 for every extra ounce of food you eat and I will make sure part of that money is used to supply food to someone who needs it. That way one can still be wasteful with food but feel good about what they are doing for the public.

How does this scheme compare with paying money which goes toward solar or wind power facilities (carbon credits)?

Quote from Xnarg : Ah, starvation began just recently. There was no starvation before we had so many people?

Not the claim I made. I merely am saying that what the article brushed off as an error is actually quite accurate.

I figured since this couldn't be explained...it must be do to global warming!

Swarm of Earthquakes Detected Off Central Oregon [foxnews.com]

GRANTS PASS, Ore. — Scientists listening to underwater microphones have detected an unusual swarm of earthquakes off central Oregon, something that often happens before a volcanic eruption — except there are no volcanoes in the area.

Scientists don't know exactly what the earthquakes mean, but they could be the result of molten rock rumbling away from the recognized earthquake faults off Oregon, said Robert Dziak, a geophysicist for the National Oceanic and Atmospheric Administration and Oregon State University.

There have been more than 600 quakes over the past 10 days in a basin 150 miles southwest of Newport. The biggest was magnitude 5.4, and two others were more than magnitude 5.0, OSU reported.

On the hydrophones, the quakes sound like low thunder and are unlike anything scientists have heard in 17 years of listening, Dziak said. Some of the quakes have also been detected by earthquake instruments on land.

The hydrophones are left over from a network the Navy used to listen for submarines during the Cold War. They routinely detect passing ships, earthquakes on the ocean bottom and whales calling to one another.

Seismic Faults 'Talk' to Each Other Before Earthquakes Hawaiian Volcano Spews Lava for First Time in 25 Years Scientists hope to send out an OSU research ship to take water samples, looking for evidence that sediment has been stirred up and chemicals that would indicate magma is moving up through the Juan de Fuca Plate, Dziak said.

The quakes have not followed the typical pattern of a major shock followed by a series of diminishing aftershocks, and few have been strong enough to be felt on shore.

The Earth's crust is made up of plates that rest on molten rock, which are rubbing together. When the molten rock, or magma, erupts through the crust, it creates volcanoes.

That can happen in the middle of a plate. When the plates lurch against each other, they create earthquakes along the edges.

In this case, the Juan de Fuca Plate is a small piece of crust being crushed between the Pacific Plate and North America, Dziak said.

Quote from Hurricane : I figured since this couldn't be explained...it must be do to global warming!

And since your rationale cannot be explained, I propose cerebral warming (proly due to alcohol).

Quote from rooobosmith : And since your rationale cannot be explained, I propose cerebral warming (proly due to alcohol).

Except I don't drink alcohol. But you are correct, when one thinks for himself as opposed to spouting theory off as some antedotal scientific law...cerebral warming is a definate side-effect! Can you explain the seismic activity off the coast of Oregon? Can you explain the two years we had deadly hurricanes in the Atlantic/Gulf several years ago? Hint: one has been attributed to MMGW (albeit incorrectly)!

Quote from Hurricane : Except I don't drink alcohol. But you are correct, when one thinks for himself as opposed to spouting theory off as some antedotal scientific law...cerebral warming is a definate side-effect! Can you explain the seismic activity off the coast of Oregon? Can you explain the two years we had deadly hurricanes in the Atlantic/Gulf several years ago? Hint: one has been attributed to MMGW (albeit incorrectly)!

So you're seriously comparing the relationship between atmospheric warming and hurricanes to that between atmospheric warming and earth quakes?

And stating that both are equally ludicrous?

The name of that logical fallacy escapes me at the moment.

Edit: Oh yeah, it's Reductio ad absurdum [wikipedia.org]