The Handwriting in the Ice Core
By EV World
Cameron Wake is an ice core paleoclimatologist by training. That means he tries to understand what earth's climate was like in the distance past by studying tiny air bubbles trapped in ancient ice. Those bubbles indicate that the concentration of carbon dioxide in our atmosphere has steadily fluctuated between 180 and 320 parts per million over the last 420 millennia.
Now readings taken in Hawaii on Mona Loa starting in the late 1950's show that those concentrations have steady risen to 380 ppm and headed towards 450 by mid-century.
Wade noted that, “a shift of 100 to 120 parts per million coincides with an ice age or an interglacial period.”
He warned that “as a result of human activities we have increased the carbon dioxide in the atmosphere equivalent to what we see in a glacial-interglacial transition. This should be of a concern to you. Just with this figure alone, I could tell you that we have dramatically changed the climate system of the earth, because we have dramatically increased the amount of greenhouse gases in the atmosphere.”
He estimates that if we continue our business-as-usual approach that by 2100 we will be at 1000 ppm, a level not seen in millions of years.
“That's going to result in considerable climate change,” which won't immediately be slowed even if we aggressively pursue a renewable energy pathway, he cautioned. This is because of the amount of CO2 we've already dumped into the atmosphere that will take a hundred years or more to be gradually re-sequestered in the oceans.
“It's a big flywheel. Even if we cut all of our carbon dioxide emissions today, there would still be a certain amount of climate change that we need to deal with.”
Wake said we have two choices, two paths we can follow: one that makes serious cuts in CO2 emissions and carbon dioxide gradually levels off at between 450 and 500 ppm, or the one we are currently on where greenhouse gases soar to 1000 ppm, a climate regime where humankind has never been before.
He went on to explain that the warming of the last 30 years has been as a result of human activity and cannot be explained by any other means including solar radiation variance or volcanism.
In the second half of his presentation, he shifted focus from the global impact of climate change to its regional impact in the U.S. Northeast. What his data showed is that over a broad region, including both urban and rural areas, here has been a steady warming of between one and three degrees Fahrenheit over the last thirty years.
Even more troubling – he used the word “shocking” -- is that Winter-time temperatures across New England have actually gone up 4.3 degrees F., which is double the increase for Summer time increase. What appears to be driving this is a inexorable decline in snow cover in a kind of accelerating feedback loop.
In practical terms, Wake said, that 4.3 degrees warming is equivalent to taking the wintertime climate of Boston and moving it south to around Philadelphia, or a New York winter and shifting it to Washington, D.C.
“These are not future predicted climate changes. This is what we've already seen in the northeast.”
Global warming climate model forecasts of extreme precipitation events are also being confirmed. Across New England the percentage of extreme weather events have doubled over the last half century.
In addition, the number of days in New England where there is snow on the ground has decreased, on average, by 25 days.
Wake and his fellow scientists took eight different climate change models and averaged them to apply to the U.S. Northeast. He told the audience that the suite did remarkably well in predicting everything we see today with the exception extreme events like the long drought in the region.
They plotted a number of different energy path scenarios, one with a heavy reliance on renewable energy and the other on heavy fossil fuel use and found that the end of the 21st century, the Boston area would expect to be anywhere from 1.5-2 degrees warming on average for the renewable energy path to 6 degrees F warmer for the fossil fuel path. For people living then, that would mean 60 and 65 days of summertime temperatures above 90 degrees F compared to the 10 days today. That is equivalent to moving Boston to Georgia.
He concluded by saying that climate change is already taking place in the U.S. Northeast, but that it appears to be taking place much faster than originally anticipated. And there will be profound changes in the climate for our children and grandchildren depending on which emissions pathway we choose.
He urged the audience to start thinking about the carbon output of everything we purchase from now on out, from light bulbs to cars to homes. Our institutions need to do the same, he added. Finally, he said we need to start asking every political candidate running for office what they plan to do about global warming and then vote accordingly.
You can listen to Dr. Wake's full presentation by using one of the two MP3 players in the right-hand column or by downloading the file to your computer hard drive for playback on your favorite MP3 device. The download URL is: http://www.evworld.com/evworld_audio/aspo06_cwade.mp3.
PowerPoint presentations from this conference are slated to be available on the ASPO USA web site.