It seems to me…
The superior man seeks what is right; the inferior one, what is profitable. ~ Confucius
I will agree, at least to some extent, with those skeptical of potentially disastrous climate-change predictions regarding global-warming. While some skepticism might be justified regarding any scientific claim or prediction, this should not be taken to imply I necessarily consider those pessimistic predictions incorrect. Science postulates laws, theorems, and axioms which, for the most part, ultimately can be only proven to be either false or not entirely correct. What is needed is more precise refinement of climate prediction models.
Our planet has been subject to climate extremes many times in the past and this would not be the first period of global warming in our planet’s history – global warming followed each of several ice ages starting in the Precambrian Period more than 600 million years ago. At the other extreme, ice covered all of Europe and most of North America 1.75 million years ago. 18,000 years ago, winter temperatures were 27 to 36 degrees cooler, ice age Florida was like Quebec.
The last great warming cycle, the Paleocene-Eocene Thermal Maximum (PETM), occurred about 56 million years ago when global temperatures increased five degrees as a result of volcanic activity and subsequent methane release from ocean floors, peat and coal fires, and permafrost melting. The primary difference between that warming cycle and the present is then the heating rise was only about 0.25 degrees centigrade per century where as now when it is increasing at a rate of 1 – 4 degrees centigrade per 100 years.
Current CO2 levels are the highest in 15 million years though they probably were even higher about 50 million years ago – of course at that time conditions on Earth were very different: CO2 concentration growth rates increased over the last ten years by 2.1 ppm a year, 40 percent higher than rate increases during the 1990s[i]. There also isn’t any disagreement that most of this increase in CO2 is anthropogenic. Projections based on the so-called Keeling Curve, initially created using precise monthly measurements by Charles Keeling of CO2 concentrations at the Mauna Loa Astronomical Observatory in Hawaii starting in 1958, are that CO2 levels will rise above 400 ppm by 2015.
Ocean temperatures have risen 1.4 degrees since 1970. Current predictions are that global temperatures could increases by as much as 10.4 degrees and for sea levels to be 3 feet higher by 2100. In addition to forcing the relocation of 150 to 200 million people by 2050, species extinction is increasing, glaciers and ice sheets are melting, coral reefs are affected by disease and heat stress, and drought and flooding are becoming increasingly common.
Deniers of climatic change are fond of pointing out that global temperature fluctuations are normal and have periodically occurred throughout planetary history. In choosing to believe these normal Milankovitch cycles[ii] might be responsible for our current warming cycle is ignoring the overwhelming evidence and unanimous expert opinion to the contrary.
If present trends persist, Earth’s climate will be very different 100 years from now. Nearly all of the world’s scientists agree on this. The only disagreement is about the extent and the rate of change. Any remaining climate-change skeptics voicing impenitence of these changes need to reexamine the obvious facts and probably consequences of any delayed response to reverse current trends.
That’s what I think, what about you?
[i]World carbon dioxide levels jump 2.3 ppm in 2008 to highest in 650,000 — if not 20 million — years, Climate Progress, 2009 February 13, http://climateprogress.org/2009/02/13/noaa-global-carbon-dioxide-co2-levels-2008/.