Monday, April 27, 2009
Measurements of atmospheric CO2 levels in northern Norway show that last week the levels hit a peak of over 397 parts per million (ppm). What was even more alarming than the actual level was the rate of increase because compared with the 2008 peak level the increase was more than 2.5 ppm. Professor of Atmospheric Physics at the Norwegian Polar Institute, Johan Strom, told The Guardian that “It is not the level of CO2 that is the problem, because the earth will adapt. What is very worrying is the speed of change. Levels [at this measuring station] are now increasing 2-3 ppm a year. The rate of increase is much faster than only 10-20 years ago. You can almost see the changes taking place. Never before have CO2 levels increased so fast.” The level of CO2 increased annually by about 1.5 ppm from 1970 to 2000 but has accelerated to about 2.1 ppm during this decade. The measurements obtained in the Arctic are typically a little higher than those obtained in Hawaii by the National Oceanic and Atmospheric Administration (NOAA). A climate scientist from the Met Office Hadley Center in Britain, Dr. Vicky Pope, said that “These are quite large numbers. It sounds like this is an Arctic phenomenon. It fits with the general increase in emissions. You would expect the concentrations of CO2 to grow.” Despite all this alarming information we still hear reports that leaders in China and India and even in the United States contend that coal needs to play a large role in meeting future energy needs. This vision of the future which includes more coal burning is not very promising.
Friday, April 24, 2009
There is more evidence that atmospheric levels of the greenhouse gas methane are trending upward again after a decade of stability. This bad news comes from the National Oceanic and Atmospheric Administration (NOAA). Methane doesn’t last nearly as long in the atmosphere as the number one greenhouse gas carbon dioxide but an equivalent amount of methane can trap much more heat. A big question is why are methane levels increasing? The answer that we do not want is that the main source of the increase is melting permafrost in the Arctic region. That would mean that the dreaded positive feedback mechanism of global warming releasing methane from the permafrost which in turn would cause more global warming, etc. has kicked in enough to show up in atmospheric measurements. Hopefully there is some other explanation.
Wednesday, April 22, 2009
With our planet heating up it would be expected that the sea ice around Antarctica would be shrinking like the sea ice in the Arctic. However, over the past few decades the reverse has been true. This contradiction of expanding ice in a warming world can be attributed to the ozone hole over the Antarctic region according to scientists from the British Antarctic Survey and NASA. In an article from Reuters the explanation given by the scientists is that their research shows that the ozone hole disrupts the wind patterns around Antarctica, causing more frequent wind to blow off the ice-covered continent and thereby cool the sea leading to more ice formation. In addition, the wind blows the existing ice away from shore leaving open sea water which becomes frozen from the cold wind. If the scientists are correct that the ozone hole is responsible for sea ice expanding rather than contracting it would seem likely that the Antarctic sea ice should start contracting at some point during this century because of global warming since it is expected that the ozone levels in the upper atmosphere will fully recover by the end of this century.
Friday, April 10, 2009
Speaking about his own personal views, President Obama’s chief scientific advisor John Holdren told the Associated Press that geoengineering could not be excluded as a possible option when it comes to addressing the problem of climate change. As reported in The Guardian, Holdren said "It's got to be looked at. We don't have the luxury of taking any approach off the table." With regard to one geoengineering scheme, cloud seeding, which could help cool the earth but also have the undesirable side effect of making the oceans more acidic, Holdren said that “We might get desperate enough to use it.” His attitude seems to be reasonable considering the alternative which is simply to try nothing if we cannot stop the buildup of greenhouse gas emissions in the atmosphere and resulting warming. However, how will we know when to try cloud seeding or some other geoengineering scheme? With a lag time of several decades between emissions and their full impact scientists may believe that the point has come long before the general public. Even today that may explain why the climate scientists are having such a difficult time translating their sense of urgency to the public.
Sunday, April 05, 2009
Within a period of only 48 hours the ice bridge that appears to hold the Connecticut-sized Wilkins Ice Shelf to the Antarctic Peninsula went from being intact to shattering. Glaciologist David Vaughan with the British Antarctic Survey told Reuters that “It’s amazing how the ice has ruptured.” Vaughn told BBC News that the ice shelf was stable for a long period time but began to retreat during the 1990s. He said that “The fact that it’s retreating and now has lost connection with one of its islands is really strong indication that the warming of the Antarctic is having an effect on yet another ice shelf.” So far during the past 50 years six ice shelves in this area of Antarctica have completely collapsed. According to Vaughn, the Wilkins Ice Shelf is soon likely to be the seventh.
Saturday, April 04, 2009
Back in January it was announced that the demise of the Wilkins Ice Shelf was imminent, with its ice bridge that attaches it to a couple of frozen islands off the Antarctic Peninsula having been reduced at its narrowest point to only a little more than 500 yards. Here it is in April and this ice shelf, which is about the size of Connecticut, is still here, but it looks like its time is about up according to a report by the Associated Press. Its ever-narrowing ice bridge was observed to have new rifts this week and a large block of ice broke off from the bridge according to the European Space Agency. Scientists are not sure whether the breakup of the ice shelf is being caused by global warming but with the average temperature having risen almost 4°F during last five decades global warming would certainly have to be seen as a possible cause. There are no ice sheets being held back from sliding into the sea by the Wilkins Ice Shelf so there is no concern about a rise in sea level from its demise. That appears to be the only good news from this unfolding event.