"Model experiments show that even if all radiative forcing agents were held constant at year 2000 levels, a further warming trend would occur in the next two decades at a rate of about 0.1°C per decade, due mainly to the slow response of the oceans. About twice as much warming (0.2°C per decade) would be expected if emissions are within the range of the SRES scenarios. Best-estimate projections from models indicate that decadal average warming over each inhabited continent by 2030 is insensitive to the choice among SRES scenarios and is very likely to be at least twice as large as the corresponding model-estimated natural variability during the 20th century. "
6°C ??
Bob at PC
________________________________________
From: Phys-l [phys-l-bounces@phys-l.org] on behalf of Jim Diamond [jiminoregon@gmail.com]
Sent: Wednesday, February 05, 2014 11:51 PM
To: Phys-L@phys-l.org
Subject: Re: [Phys-L] Garth Paltridge: Climate Change's Inherent Uncertainties
Here are a few of the indicators of the real situation:
* nearly unprecedented loss of arctic sea ice (even including supposed gain
in antarctic sea ice)
* rapidly increasing sea level rise exceeding the rate of rise of any model
of the IPCC
* rapidly increasing ocean heat content, at depths as low as 2 km below the
surface
* a forty year record of decline of northern hemisphere snow and ice that
will lead to a loss of almost all permanent ice outside of Greenland and
the high mountain regions by 2050.
These are not models. These are observations.
In my opinion, the worst way to measure the effects of global warming is to
use surface temperatures. This is like trying to measure the temperature of
a beaker of liquid water by suspending a thermometer a few microns above
the surface of water and measuring the temperature of the air above, while
putting the entire apparatus in the back of a pickup and driving around
into the sun and back into the shade with no attempt to control sloshing in
the beaker. It is no surprise that surface temperatures show such wide
variance. The best way to measure the temperature of the beaker of water is
to immerse the thermometer in the liquid, then measure the temperature.
That is what we have done with the ARGO float data for a decade, and the
data is bad news.
We are the frog slowly cooking in the pot.
Imagine that! By 2050, almost all northern hemisphere snow and ice cover
will be seasonal, not permanent, but for Greenland and the highest
mountain regions. If you don't think this is a substantial alteration of
earth's ecosystem, IMO there is something wrong with your logic.
Now, a little less than 50% of cumulative emissions are due to OECD plus
BRIC and Indochina; the rest of the world has the responsibility for the
rest. I see little prospect of controlling the emissions outside of the
OECD nations.
I don't think we will avoid a 4°C increase in global surface temperatures;
we might even hit 6°C if we keep accelerating our emissions at the present
rate. I suspect that it is highly likely that Andy Dessler and Michael Mann
are correct that climate sensitivity is likely to be much larger than 3.15°C.
Cloud feedback appears to be dominated by trapping by low-level clouds of
IR radiated by the earth , not by changes in albedo due to upper-level
clouds.
There are plenty of references to back up these data. Just look for
yourself.
Happy Year of the Horse
恭喜发财。 身体健康！
Jim
--
James J. Diamond, Ph.D.
Department of Chemistry
Linfield College
McMinnville, OR 97128
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