Climate Science 2009...Summary by Joe Romm

Climate Science 2009A Summary by Joe Romm
www.climateprogress.org

romm_1005.jpg2009 was the year the scientific literature caught up with what top scientists have said privately for years. Key aspects of our climate are changing faster than expected. If we stay on our current emissions path, we face incalculable catastrophe.In 2009, the scientific literature caught up with the expert grapevine. Many predicted impacts of human-caused climate change are indeed occurring much faster than anybody expected, and all across the planet — particularly ice melt.
If we stay anywhere near our current emissions path, we are facing incalculable catastrophes by century’s end, including rapid sea level rise, massive wildfires, widespread dust-bowlification, large oceanic dead zones, and 9°F warming. Much of it will be all but irreversible for centuries. The consequences for human health and well being are going to be extreme. 

That’s not a  surprise to anybody who has talked to leading climate scientists in recent years. But it's a scientific reality only about 2% of people fully grasp. Here, then, I will review the past year of peer-reviewed climate science literature.

Heat-trapping greenhouse gases are at unprecedented levels, and the paleoclimate record suggests that even slightly higher levels are untenable:

* World carbon dioxide levels jumped 2.3 ppm in 2008. 
* CO2 levels are the highest for 15 million years, when it was up to10°F warmer and seas were up to 120 feet higher.
* World Meteorological Organization & NOAA; 2000-2009 was hottest decade on record.
Antarctica has warmed significantly over past 50 years 
EAST Antarctica is losing mass, and may soon contribute significantly to sea-level rise. 
Dynamic thinning of Greenland and Antarctic ice-sheet ocean margins is pervasive & enduring.
A major Antarctic glacier is being lost at accelerating exponential rate like nothing else in the natural world.
The North Pole is poised to be largely ice-free by 2020.* Bolivia’s 18,000 year-old Chacaltaya glacier completely disappeared
The world’s glaciers shrank for the 18th successive year

Given this unexpectedly fast ice melt, seas level rises will be much higher & faster than previously thought:

Sea levels may rise 3 times faster than IPCC estimated, hitting 6 feet by 2100. 
Faster Greenland ice sheet melting could raise U.S. East Coast sea levels >6 feet by 2100
West Antarctic ice sheet collapse would be catastrophic for U.S. coasts. 

Dangerous positive carbon-cycle feedbacks threaten to amplify human-caused GHG effects:

“Clouds Now A Big, Bad Player in Global Warming” — an amplifying feedback. 
So many amplifying methane feedbacks; so little time to stop them all. 
* Global warming is killing U.S. trees, another dangerous carbon-cycle feedback. 

High emissions levels + positive feedbacks = climate catastrophe:

M.I.T. doubles its 2095 warming projection to 10°F — with 866 ppm and Arctic warming of 20°F 
Definitive NOAA-led report on U.S. climate impacts warns of scorching 9 to 11°F warming over inland U.S. by 2090 — and that 's just business as usual!” 
Ocean dead zones to expand and “remain for thousands of years” 
The worst-case IPCC scenario trajectories are being realised” — 1000 ppm 
Climate change expected to increase Western wildfire burn area as much as 175% by 2050 
Climate change “largely irreversible for 1000 years,” with permanent Dust Bowls in Southwest and around the globe 

Seriously bad news for human health and welfare:

* The Lancet : Cutting greenhouse gas emissions has major direct health benefits 
* NRC: Fossil fuels cost the U.S. $120 billion/year 
"Global Warming Is A Medical Emergency”
Half world’s population could face climate-driven food crisis by 2100 

The time to act is most certainly now. 

Let's end this summary with the best piece of scientific news; one that suggests it is not too damn late to act! A NOAA-led study found we have not yet activated strong climate feedbacks from permafrost and methane hydrates. So far that most dangerous of all feedbacks — Arctic and tundra methane releases — does not appear to have been fatally triggered.

The anti-science crowd use smoke and mirrors to distract as many people as possible, but the rest of us need to listen to the science and keep our eyes on the prize — reversing greenhouse gas emissions trends as quickly and rapidly as possible.      
In 2009, Time Magazine named American physicist and climate expert Joe Romm one of itsHeroes of the Environment. The son of a newspaper editor, he is now the Web's most influential blogger in the field of climate and energy. Romm gained his PhD from MIT. When working for the Rockefeller Foundation, he identified energy & climate change as 'sleeper issues' that would dominate the coming decades. He then became assistant secretary at the Clinton Department of Energy. His 2006 book on global warming, Hell & High Water, is essential reading in the field.