Oxford Prof. - "Two Degrees C Is Already Gone As A Target . Four Degrees C Is Definitely Possible."

[hatrack]

UXBRIDGE, Canada, Oct 9 (IPS) - The prospect of a four-degree Celsius rise in global average temperatures in 50 years is alarming - but not alarmist, climate scientists now believe. Eighteen months ago, no one dared imagine humanity pushing the climate beyond an additional two degrees C of heating, but rising carbon emissions and inability to agree on cuts has meant science must now consider the previously unthinkable.

"Two degrees C is already gone as a target," said Chris West of the University of Oxford's UK Climate Impacts Programme. "Four degrees C is definitely possible...This is the biggest challenge in our history," West told participants at the "4 Degrees and Beyond, International Climate Science Conference" at the University of Oxford last week.

A four-degree C overall increase means a world where temperatures will be two degrees warmer in some places, 12 degrees and more in others, making them uninhabitable. It is a world with a one- to two-metre sea level rise by 2100, leaving hundreds of millions homeless. This will head to 12 metres in the coming centuries as the Greenland and Western Antarctic ice sheets melt, according to papers presented at the conference in Oxford. Four degrees of warming would be hotter than any time in the last 30 million years, and it could happen as soon as 2060 to 2070.

"Political reality must be grounded in physical reality or it's completely useless," John Schellnhuber, director of the Potsdam Institute for Climate Impact Research, told the conference. Schellnhuber recently briefed U.S. officials from the Barack Obama administration, but he says they chided him that his findings were "not grounded in political reality" and that "the Senate will never agree to this".

EDIT

(Ed. - emphasis added)

http://www.ipsnews.net/news.asp?idnews=48791

[The Traveler]

1. Different mindsets

One problem with our system of government is that it provides ample opportunity for the legal mindset or the economic mindset to find expression and shape policy. The findings of scientific minds must be filtered through "the political reality". Politicians are always paying lip service to the value of scientific knowledge and technological prowess ... and they are always eager to ignore either or both if the political landscape is threatened thereby.

But, as dude points out, mother nature doesn't care about our political reality. The laws of physics operate without regard to human aspiration. We are approach a time of bitter lessons in that regard, undone by a failure to master the development of our own technology. It didn't have to be this way. We could have dealt with these issues 30 years ago and would be sitting pretty right now had we done so. We definitely could have invented our way out this problem. We chose this path to satisfy the hunger of stock exchanges for short term profits.

Trav

[populistdriven]

2. the warmest year recorded globally was not in 2008 or 2007, but in 1998.

http://news.bbc.co.uk/2/hi/science/nature/8299079.stm

i know its coming...



denier!!

[GliderGuider]

3. From RealClimate.org:

A warming pause?

The blogosphere (and not only that) has been full of the “global warming is taking a break” meme lately. Although we have discussed this topic repeatedly, it is perhaps worthwhile reiterating two key points about the alleged pause here.

(1) This discussion focuses on just a short time period – starting 1998 or later – covering at most 11 years. Even under conditions of anthropogenic global warming (which would contribute a temperature rise of about 0.2 ºC over this period) a flat period or even cooling trend over such a short time span is nothing special and has happened repeatedly before (see 1987-1996). That simply is due to the fact that short-term natural variability has a similar magnitude (i.e. ~0.2 ºC) and can thus compensate for the anthropogenic effects. Of course, the warming trend keeps going up whilst natural variability just oscillates irregularly up and down, so over longer periods the warming trend wins and natural variability cancels out.

(2) It is highly questionable whether this “pause” is even real. It does show up to some extent (no cooling, but reduced 10-year warming trend) in the Hadley Center data, but it does not show in the GISS data, see Figure 1. There, the past ten 10-year trends (i.e. 1990-1999, 1991-2000 and so on) have all been between 0.17 and 0.34 ºC per decade, close to or above the expected anthropogenic trend, with the most recent one (1999-2008) equal to 0.19 ºC per decade – just as predicted by IPCC as response to anthropogenic forcing.

[populistdriven]

4. they summarize it well, but the difference between the northern and southern data

points to carbon black being a far larger contributor than anyone is publicly discussing

i think the administration quote was stated out of context

this IS a political decision at the moment and we should pass cap and trade simply for the energy security and economic benefits

[OKIsItJustMe]

8. Well, at least it's been discussed here

I've personally posted a number of studies and stories regarding "black carbon."

http://demopedia.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=115&topic_id=140010&mesg_id=140010

[pscot]

7. It's worth noting

that for the last 3 or 4 years we've been in a an unusually quiet solar minimum. In the last year there have been more than 200 days with no sun spots. Solar minima correspond with less solar radiation reaching the earth. As the sunspot cycle ramps up again the hiatus in the warming trend is likely to end.

If summer temps in Phoenix rose 12 degrees, the place would be uninhabitable.

[The Traveler]

11. Quite true ... but not all that significant

Average temperature is at best a noisy characteristic variable. Take a plot of that measure over the past 50 years. You can see the value jiggle wildly up and down ... like I said it is a noisy variable ... but you can also see the general trend develop. It is quite apparent to even the unpracticed eye. 1998 certainly stands out as being way off the curve. Still, a least squares fit of the data gives you an accelerating function like an exponential, and that agrees with what your eyes tell you as you regard the curve. Good curve fitting procedures are not thrown off by a wild sample like 1998, and the curve itself is what significant in this discussion. 1998 freaked a lot of people ... but 1999 fit nicely along the curve ...

If carbon emissions are NOT resulting in heat trapping, then I would dearly love to know what physical processes are preventing that from occurring. Any model of climate that claims carbon emissions are NOT playing a role must be able to explain why. Given the precipitous decline in photosynthetic capacity of bio-systems over the past 50 years, it is difficult to come up with the numbers that suggest plant life is taking advantage of the additional CO2. And, of course, CO2 is only one of the carbon forms being injected into the atmosphere. Methane release from melting permafrost and warmed Arctic sea floors seems to be playing an ever more significant role ... and methane is a much more effective greenhouse gas than CO2.

Recent discussion regarding the role of ocean currents (a MAJOR thermal transport system 'round these parts ... by which I mean planet Earth) in climate change are more than a little interesting. A model (unfortunately advocated by certain right wing political figures) based on these considerations has recently been proposed, and it does "backfit" the data reasonably well (as does the carbon model). While the politically and economically motivated "global warming deniers" are quick to seize on this alternative model, I am more skeptical. Again, if carbon emissions of the magnitude we are producing are NOT a contributing factor, then what processes are preventing that? This model makes no attempt to address that question. Still, the proposition that shifts in ocean currents may be a more significant factor than atmospheric carbon levels in climate is not at all unreasonable. The good news is the two models diverge in predictions rather quickly, so we'll know for sure in a few years which is better. Regrettably, we are not likely to enjoy the answer.

Trav

[Birthmark]

6. +1

Very well stated and accurate. I couldn't agree with you more.

[RaleighNCDUer]

5. Finally!

Somebody actually making a prediction that I can't dismiss as being too optimistic.

For the last 15 years I've been watching the predictions, and the whole time I've been saying "nope - it'll be worse than that". People predicting an 18cm rise in the oceans by the end of the century, because that is half-again the increase of the past century - as if that was some kind of guideline.

12 meters. Complete loss of the Greenland ice sheet by 2050ish. Methane release creating a feedback loop - I know it doesn't persist as long as CO2, but it is much more active, and during the 7 years or so that any particular methane release is active, there will be enough warming to release still more trapped methane, so we're not talking about a 7 year spike, but a 50 year trend, at the minimum.

We've PASSED the tipping point.

[Bigmack]

12. Wouldn't the "dumping" into the North Atlantic of all

the freshwater, Greenland ice mean a significant shift southward for the thermohaline current? But then I live on the west coast, so no problemo. Ms Bigmack

[joshcryer]

13. This is so true. So many predictions err on the conservative side. IPCC 5 is going to...

...whitewash the issues that have been being discovered and analyzed daily, such as ice melt. It's going to be horrific.

[CHIMO]

9. Only

When nature responds, will there be any real action.

The polar caps are decreasing, sucking up extra energy and still the permafrost is disappearing.

Studies won't mean anything if one is trying to correct things.

The studies will be usefull once nature starts exerting its power.

[Nederland]

10. The problem is...

...nature responds so slowly. Four degrees spread out over decades is not the kind of thing that results in a single catastrophic event that changes minds.

[joshcryer]

14. Ice melt, acidification, and methane release are not short term events.

They happen, from what we understand, over the span of a very short time period.

We release 30 billion tonnes of CO2 a year. Once the oceans can no longer absorb it, the next 30 billion tonnes of CO2 becomes some billion tonnes of acid in the seas.