Tipping Points Could Be Closer Than We Thought

Cross-posted from THE ENVIRONMENTALIST

An international team of experts has submitted a report that lists nine tipping elements — areas of concern for lawmakers — that quantify how much time is left to address their impending impact.

Produced by scientists from the U.K, Germany and the U.S., the study states: “Society may be lulled into a false sense of security by smooth projections of global change,” and goes on to predict the critical threshold at which a small change in human activity can have large, long-term consequences for the Earth’s climate system.

“These tipping elements are candidates for surprising society by exhibiting a nearby tipping point,” the report states. “Many of these tipping points could be closer than we thought,” said lead author Timothy Lenton, of the University of East Anglia in England. “Our findings suggest that a variety of tipping elements could reach their critical point within this century under human-induced climate change.”

Link to the list below the jump…

The report lists nine tipping elements that are at risk and the projected timing within which they could begin to tip the overall climate (with the caveat that the models could change in certainty as conditions change)

Indian Summer Monsoon (within ~one year).

Africa Rainfall (within ~ten years).

Arctic Sea-Ice (within ~ten years).

Boreal Forest (within ~fifty years).

Amazon Rainforest (within ~fifty years).

El Niño Southern Oscillation (within ~one hundred years).

Atlantic Thermohaline Circulation (within ~one hundred years).

Greenland Ice Sheet (within ~three hundred years).

West Antarctic Ice Sheet (within ~three hundred years).

Link here for the explanation of the climate impact for each item on the list.  

The report plays down the fears of a sudden permafrost melt releasing excessive methane, and that a “shutdown of the Gulf Stream in the Atlantic Ocean that brings warm water north to Europe appears to be a less immediate threat.” The caveat there is that the report was based on a 2005 workshop of 36 leading climate scientists, a survey of 52 other experts, and a review of scientific literature. The information will require reevaluation as the models change to determine changes in sensitivity and certainty.

Citations:

Post originated from THE ENVIRONMENTALIST

Journal article: Lenton, T. M., Held, H., Kriegler, E., Hall, J. W., Lucht, W., Rahmstorf, S. and Schellnhuber, H. J. (2008). Tipping elements in the Earth’s climate system. Proceedings of the National Academy of Sciences, Online Early Edition. February 4, 2008.

Potsdam Institute for Climate Impact Research (2008, February 7). Tipping Elements In Earth’s Climate System. ScienceDaily. Retrieved February 6, 2008, from ScienceDaily