From today's Washington Post ~ U.S. Completes Warmest 12-Month Period in 117 Years. "Dating back to 1895, never has the U.S. strung together 12 straight months warmer than May 2011 to April 2012, according to new data released today by NOAA's National Climatic Data Center (NCDC) .... As warm as it's been, it's no surprise that the calendar year 2012 (spanning January to April) is off to a record warm start, 5.4 degrees F above average across the Lower 48 [see image below, click to enlarge] .... The degree by which some states and regions have exceeded their norms so far this year is incredible, and record-setting. North Dakota's temperature so far this year is 10.4 degrees above normal. That's the biggest warm anomaly for the first 4 months of the year on record for any state .... The U.S. Climate Extremes Index ~ that tracks extremes in temperatures, precipitation, and tropical cyclones ~ showed a record 42 percent of the country experienced extreme weather during the first four months of the year, primarily exceptional warmth .... At least 332 locations (mainly located in the Rockies and Southern Plains) soared to their warmest April temperature on record .... April snow cover extent was third smallest on record.
" .... This onslaught of record-breaking warm weather over the Lower 48 this year is related to a jet stream pattern which has locked up cold air in the higher latitudes and favored sprawling heat domes over the mid-section of the country which have meandered east and west at times. Although the contortions of the jet stream established the unusually warm weather patterns, the intensity and persistence of the warmth compared to the past is likely related to the elevated greenhouse gas concentrations in the atmosphere from human activities."
It's not just the heat, it's the wet. As anthropogenic (man-made) climate change warms the atmosphere, the world ocean, and the earth, glaciers and ice caps melt at an alarming rate, adding to the rise in sea level which is compounded by the fact that warmer water expands. That's bad news for human communities in low-lying areas, such as coastal cities or island nations. Millions of people in the U.S. alone live only a few feet above sea level. Think Boston, New York City, Philadelphia, Washington DC, Charleston, Miami, New Orleans, Los Angeles, San Francisco, Seattle. The future is now ~ a feature on the PBS program Need to Know reports that "The city of Norfolk, VA, is getting an early look at what sea level rise means for a big coastal community. The city is experiencing sea level rise earlier than most because not only are the seas around the city going up, but much of the land beneath Norfolk is going down. This one-two punch means the city is seeing today the kind of flooding that many cities could experience down the road if the scientific projections of sea level rise play out.
" .... A bit of additional background ~ sea levels globally have gone up about 5-8 inches over the last century ~ a side-effect, most scientists say, of our heavy use of fossil fuels like coal, oil, and gas. Burning those fuels warms the planet [by producing greenhouse gases], and warmer ocean water expands, causing the seas and oceans to rise. The federal government projects that sea levels will rise an additional foot or two in coming decades. If the planet continues to warm, the world's ice sheets could continue to melt, releasing more of their water into the seas, which could drive sea level up much further."
Check out the embedded video in the Need to Know segment for a glimpse of what lies ahead for more and more people around the globe. Low-lying Pacific island communities and nations will simply disappear beneath the rising sea.
So getting back to temperature for a moment ~ given a global rise, one envisions tropical climates migrating slowly toward the Earth's poles, and temperate climates doing the same. But consider this ~ climate migration will also rise in altitude. Already all the glaciers which gave Glacier National Park its name have disappeared, or shrunk to the brink of extinction. Plant, animal, bird, reptile, and fish species will (if possible) follow the climates they have adapted to over evolutionary time. But what happens if (a) they run out of places higher in latitude, or (b) they run out of places higher in altitude?
Consider the flora and fauna of tepuis, sheer-sided, flat-topped mountains in the Amazon basin. Featured in Arthur Conan Doyle's 1912 novel The Lost World, and again in the 2009 animated film "Up", tepuis are host to species found nowhere else on earth. Each tepui is an island in the sky. A NYTimes article explains these towering, exotic land forms more fully, and recounts research on how the species at the tops could have arrived there, and when. Prophetically, the article ends thus ~ "There may not be much time left to gather data. Global warming has been driving mountain-dwelling species to higher altitudes, and will drive them up even farther. But the frogs and other species that are dound only on top of tepuis have already gone as high as they can go. They're just going to go extinct."
Humans have cause the extinction of countless species in all parts of the world through intentional eradication, and through mindless overhunting and overfishing. We have driven our fellow creatures into the precincts of distant memory simply by the sheer weight of our numbers, expanding to destroy native habitat. But extinction by means of climate change seems the most insidious method of all ~ and one which may take us along for the ride.
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