The headline would have been more accurate if it said, «World poised to
see accelerated warming in the coming decade.»
«When we look at actual climate data, however, we do not
see accelerated warming in the tropical troposphere.
Not exact matches
Safety concerns over fracking are overblown — but so are the boosterish claims made for its environmental and economic benefits (
see «Fracking could
accelerate global
warming» and «Frack on or frack off: Can shale gas really save the planet?
«It's fair to say that over the next couple of decades, we would expect to
see the trend reverse, and internal variability
accelerating the
warming.»
The combination of global
warming and
accelerating sea level rise from Greenland could be the trigger for catastrophic collapse in the WAIS (
see, for instance, here).
Climatologists reporting for the UN Intergovernmental Panel on Climate Change (IPCC) say we are
seeing global
warming caused by human activities and there are growing fears of feedbacks that will
accelerate this
warming.
The
accelerated loss of sea ice should come as no surprise given that another study presented at the AGU meeting found
accelerated Arctic
warming (
see NSIDC: Arctic melt passes the point of no return, «We hate to say we told you so, but we did»):
The relevance of the models has to do with your point that by 2100 we will
see 3 - 4 degrees C
warming and that therefore the ice melt is bound to
accelerate.
[Response: I still don't
see why you think that the
warming will
accelerate much faster than the models suggest since they include these mechanisms.
I certainly have
seen references to
accelerated warming in the press, and I do think what they really have in mind is something like «
accelerated impacts of
warming,» which would be a fairer description of what has been coming out in the scientific literature.
I don't
see why Romm comes down so hard on this, though he has a point that the coverage could have made it a lot clearer that the interrupted
warming of the next several years will be made up for
accelerated warming sometime after 2010, so that in the end you wind up at the same place the uninitialized climate models say you would be.
But because that
warming is now dominant,
see comment 75 #, the Arctic
warming will certainly
accelerate.]
However, I would keep in mind the fact that over a decade's time, we have
seen more than a doubling of the rate of loss of mass balance in Greenland, a tripling in icequakes, the
warming of the West Antarctic Peninsula resulting in the acceleration of glaciers, the
accelerating loss of global glacier mass balance, etc..
And, quite disturbingly, with a manifest
warming of only 0.8 ºC, we are already
seeing effects − such as the precipitous receding of the Arctic sea ice − that are not only dangerous in themselves but also producing positive feedbacks that
accelerate the
warming.
You may have
seen it before in another form, perhaps while reading part 10 of this series, explaining biodiversity loss
accelerates under
warming — based on that same study.
There is no real debate in the peer - reviewed scientific literature over the fact that the unusual,
accelerating global
warming seen since the 19th Century is attributable to the increase of greenhouse gases, primarily carbon dioxide, in the atmosphere due to burning fossil fuels.
These patterns provide the peaks and valleys that we
see, yet we can still detect the underlying
accelerating warming trend.
But, hey, that last 30 year «
accelerated»
warming cycle ended after 2000 — since then we are
seeing a slight cooling cycle (as we did for the 30 years or so before 1970).
I say «more or less» because one could argue from the data (as we'll
see below) that the
warming rate during recent years has upticked with the warmth in 2010 indicating a
warming that is occurring faster than projected and is
accelerating.
Looking at a much longer time span, we
see that the long term [natural] global
warming trend is not
accelerating.
But I am now a «lukewarmer» who has yet to
see any evidence saying that the current
warming is, or is likely to be, unprecedented, fast or tending to
accelerate.»
Since to me (and many scientists, although some wanted a lot more corroborative evidence, which they've also gotten) it makes absolutely no sense to presume that the earth would just go about its merry way and keep the climate nice and relatively stable for us (though this rare actual climate scientist pseudo skeptic seems to think it would, based upon some non scientific belief —
see second half of this piece), when the earth changes climate easily as it is, climate is ultimately an expression of energy, it is stabilized (right now) by the oceans and ice sheets, and increasing the number of long term thermal radiation / heat energy absorbing and re radiating molecules to levels not
seen on earth in several million years would add an enormous influx of energy to the lower atmosphere earth system, which would mildly
warm the air and increasingly transfer energy to the earth over time, which in turn would start to alter those stabilizing systems (and which, with increasing ocean energy retention and
accelerating polar ice sheet melting at both ends of the globe, is exactly what we've been
seeing) and start to reinforce the same process until a new stases would be reached well after the atmospheric levels of ghg has stabilized.
The modest global
warming seen to - date (around 0.13 degrees Celsius per decade) is likely to
accelerate over the coming century - and models have even the US Corn Belt in the firing line.
In fact, if we continue on our current path of high heat - trapping emissions, the region is projected to
see forest fires during June and July at two to three times its current rate.2, 6 Some 1 billion metric tons of organic matter and older - growth trees could burn7, 15 —
accelerating the release of stored carbon and creating a dangerous global
warming amplification or feedback loop.5, 14
But aren't we
seeing an
accelerating trend in the long term
warming recently rather than a slowdown?
Although the globe has
warmed since 1988 (not rapid, nor
accelerating,
see here and here), the trend for Canadian boreal forest fires has been the opposite of that predicted over the 27 years after the Hansen 1988 testimony.
However, this trend seems unlikely to continue, and we will probably
see accelerated surface
warming in the coming decades.
1998 was near the tail end of a decade that jumped well above the mean average longer term rate of increase (there is a thing called climate variability, it didn't disappear with climate change, and if anything probably only intensified;, and ocean
warming and glacial melt both
accelerated during this period, taking more energy out of the air —
see below).
(And I still can't
see how a newly open and increasingly
warm summer Arctic Ocean won't produce more water vapor, vapor whose GHG properties will further
accelerate Arctic
warming — or is that completely offset by increased cloud formation??)
Second, this general prediction «'' internal variability leading to slower than expected
warming in recent years through 2010, followed by
accelerated warming «'' is almost exactly the same prediction that the Hadley Center made last summer in Science (
see here).
The rate of
warming has
accelerated over the past 30 years, the agency reports, increasing globally since the mid-1970s at a rate approximately three times faster than the trend as
seen over the entire past century.