Ice Out

NASA issued a report on March 18th that identifies a disturbing trend of decreasing perennial sea ice in the Arctic despite this year's colder weather and the expansion of new ice. 

"the scientists said they believe that the increased area of sea ice this winter is due to recent weather conditions, while the decline in perennial ice reflects the longer-term warming climate trend and is a result of increased melting during summer and greater movement of the older ice out of the Arctic.

Perennial sea ice is the long-lived, year-round layer of ice that remains even when the surrounding short-lived seasonal sea ice melts away in summer to its minimum extent. It is this perennial sea ice, left over from the summer melt period, that has been rapidly declining from year to year, and that has gained the attention and research focus of scientists. According to NASA-processed microwave data, whereas perennial ice used to cover 50-60 percent of the Arctic, this year it covers less than 30 percent. Very old ice that remains in the Arctic for at least six years comprised over 20 percent of the Arctic area in the mid to late 1980s, but this winter it decreased to just six percent.

According to Walt Meier of the National Snow and Ice Data Center at the University of Colorado, Boulder, as ice ages it continues to grow and thicken, so that older ice is generally also thicker ice. This winter the ice cover is much thinner overall and thus in a more vulnerable state heading into the summer melt season."

Last year, Arctic sea ice loss during the summer melt season blew away all records since satellite measurements began in 1979. 

These are data points.  They describe conditions outside of seasonal norms.

Here is another data point analyzing increasing trends in sea level rise.  There are two major influences on sea level rise: thermal expansion with warmer ocean temperatures (which National Geographic says has already raised ocean levels between 4-8 inches and melt water from ice sheets.

You do not have to subscribe to the theory of anthropogenic global climate change to recognize that change is occurring.  What you do with that information depends on what you believe is the proper role of governments and individuals in changing behavior and whether anything that our species can do will mitigate the change that these data and countless other data points represent.

Comments

[Tim Abbott]

Ben, wonderful to hear from you. I was reading about the efundja and even blogged some about it here: http://greensleeves.typepad.com/berkshires/2008/03/too-much-of-a-g.html but your news exceeds imagining.

[Ben Fuller]

Tim, getting back into blogging and things after the operation last year. Suppose it means I'm recovered.

Some global warm,ing things things from Namibia. First, there are the floods in the North. The Cuvelai Oshana system has burst. About 65,000 people are displaced. Whole towns are cut off, business, schools etc., flooded. A few weeks ago the road between Ondangwa and Oshakati was impassable. No one has any memory of an efundja of this magnitude. In many areas up there crops have been washed away so there will be some serious hunger. With all that water we expect a bumper malaria season soon.

Second. Windhoek is having another year of heavy rains. This is the second in three seasons. Here at my house we are over 600 mm when the norm should be 350. There have been some theories that the Intertropical Convergence Zone may actually move further away from the Equator as a result of Global Warming. Like this year and 2005/06, it settled in around Tsumeb instead of up in Angola, which brings heavier rains to central and Southern Namibia. If the theory holds true, we may have a wetter climate, but the deserts of Southern Namibia and the Northern Cape would move South, which does not bode well for Cape Town and all the agricultural production that goes on in the Eastern and Western Cape as well as Natal. Worth keeping an eye on this.

Lastly, with a predicted rise in the oceans, and the prices of land down in Swakopmund still spiraling out of control, I'm thinking of finding a way to buy land about 2-3 kilometers back from the coast. It's worthless desert right now, but for my grandchildren could be a nice investment. :-) Seriously, what is shocking is the way some very pricey houses are literally a couple of meters from the shoreline. A couple centimeters rise, and those houses will be in serious trouble.