Looking back — 2012 was a year for the record books—the hottest year on record in the U.S. Flooding threatened millions in Australia, China and Nigeria, while the western U.S. suffered from severe drought. High water in flood-prone San Mark’s Square in Venice became the norm.
Arctic sea ice has been retreating for years, but it shrank to its lowest level in recorded history this past summer. NASA’s incredible photos of Greenland’s rapidly melting ice sheet were alarming because ice reflects a large part of solar radiation back into space.
Permanently frozen ground across Siberia and Alaska that contains vast stores of carbon dioxide, trapped for thousands of years, has started to thaw, bringing with it the threat of a big increase in global warming —perhaps by 5-9 degrees F by 2100. That is far above a ceiling of 3.6 degrees F set by almost 200 nations at climate talks in 2010.
There was definitely a “new reality” when it came to weather patterns in the U.S. this year. Superstorm Sandy was the final straw for many and brought back climate change conversations—even among former climate change skeptics. “Fear death by water,” T. S. Eliot intoned in “The Waste Land.” Many now do.
The Mississippi River is in danger of closing to commercial barges after the worst drought in the Midwest in half a century—after historic flooding in that area in the spring of 2011. Farmers there lost up to three-quarters of their crops this year. Releasing water from the Missouri River would help the barges, but hurt the farmers in Montana and Nebraska. The recent Ken Burns series about the Dustlands showed the dire state of farmlands after duststorms in the 1930s. Could it happen again? The East Coast’s Intracoastal Waterway (ICW to us boaters) has similar problems and insufficient funding to dredge it regularly.
Worried? You might worry about Mount Kilimanjaro too, even if you deny climate change. Its snowy top has been diminishing for more than a century—decades before climate change entered our vocabulary. Between 1912 and 2011, this icy cap decreased by more than 85 percent. Decreasing snowfall and deforestation play a role but increasing radiation from the sun is the major factor. With less cloud cover, the snow transforms directly from ice to water vapor without melting.
So Kilimanjaro remains a poster child for global warming. Predictions for the demise of its snowy top now range from 7-30 years. A few years ago, I saw remarkably smaller glaciers in Montana’s Glacier National Park than in past photos.