Greenhouse gas levels again reach record highs, wtih CO2 crossing 400 ppm threshold for the first time in the anthropocene — last tine CO2 was this high, Earth was a much warmer place, with sea levels 20 feet higher than now …
FRISCO — Last year brought more sobering signs of continued global warming, including record-warm temperatures 20 meters below the ground on Alaska’s North Slope, federal scientists said today, releasing the 2013 State of the Climate report (Blunden, J., and D. S. Arndt, Eds., 2014: State of the Climate in 2013. Bull. Amer. Meteor. Soc., 95 (7), S1-S238).
With heat-trapping greenhouse gases reaching record levels in 2013, “the state of the climate is changing more rapidly than at any time in … in the known record,” said National Oceanic and Atmospheric Administration director Thomas Karl, outlining the findings in the agency’s annual climate check-up. Read the full report here: http://www.ncdc.noaa.gov/bams-state-of-the-climate/2013.php.
The deep permafrost melt in the Arctic is probably linked with declining spring snow cover in the region, scientists said, highlighting a steady decline in the northern hemisphere’s reflective blanket of high latitude snow — think of the sunshade you use in a car windshield.
A major meltdown of Arctic permafrost would probably send a surge of potent heat-trapping methane gas into the atmosphere, intensifying the global warming spiral. Combine the melting on the North Slope with rising sea level and less sea ice (which means more waves lashing the shore) and you have a recipe for crumbly erosion, already happening at a record rate in some places.
According to NOAA, 2013 will probably mark the 24th year consecutive year of retreat for mountain glaciers worldwide, adding up to a water loss of more than 2 feet. Even if the global average temperature doesn’t spike to new records every year, the long-term trend is still downhill for glaciers, which will have a huge impact on water supplies for millions of people.
From the report:
|Region||Status as of 2013|
|Austria (the Alps)||93 retreating, 1 advancing, 2 stable|
|Norway||26 retreating, 3 advancing, 4 stable|
|North Cascades (WA), Alaska||all 14 glaciers had significantly negative mass balance|
|New Zealand||altitude of the end-of-summer snow line for all 50 observed glaciers was farther up the mountain than would be required for the glaciers to grow|
|Nepal||3 glaciers near equilibrium, accumulation the highest of last 7 years|
2013 will also go down in climate history as the year atmospheric carbon dioxide levels climbed above 400 parts per million for the first time in human history. That level later dropped again, but has spiked back above the benchmark and stayed high for several months this year.
Reaching the 400 ppm threshold won’t trigger a sudden calamity, but it’s a clear symptom of the long-term problem. Even if emissions of greenhouse gases were to stop right away, temperatures will climb for a long time to come. Levels of other major greenhouse gases also reached record levels, the NOAA scientists said.
New analyses of existing weather station data are also enabling climate researchers to tease out different types of trends, including indices that measure the change in extreme cold and extreme warm temperatures over time. “Extreme” is defined as in the top (or bottom) 10 percent relative to the late 20th Century.
“The analyses shows that, in general, the parts of the world where we have sufficient data (North America, Europe, Asia, Australia) are seeing larger extents of extreme-warm maximum temperatures (afternoon highs), and smaller extents of extreme-cool minimum temperatures (morning lows), said Deke Arndt, chief of the climate monitoring branch at NOAA’s National Climatic Data Center.
Crunching the climate numbers for the past few decades doesn’t result in good news for the Southwest, where precipitation has been running below average for years on end.