Tuesday, February 5, 2008

Issues Making Sense

Journal Entry- Tuesday, February 5, 2008.

It is all making sense now. Linkage. It is important to pull little bits out over time and connect them. Yesterday I posted something very interesting which has been gnawing at me for some time like a carcass left out in Nunavut.

Tipping points. We are seeing them NOW.

Published on Tuesday, February 5, 2008 by The Independent/UK
Scientists Identify ‘Tipping Points’ of Climate Change
by Steve Connor

Nine ways in which the Earth could be tipped into a potentially dangerous state that could last for many centuries have been identified by scientists investigating how quickly global warming could run out of control.

Professor Lenton added: “But we should be prepared to adapt, and to design an early-warning system that alerts us to them in time.”

Irreversible changes

* Arctic sea ice: some scientists believe that the tipping point for the total loss of summer sea ice is imminent.
* Greenland ice sheet: total melting could take 300 years or more but the tipping point that could see irreversible change might occur within 50 years.
* West Antarctic ice sheet: scientists believe it could unexpectedly collapse if it slips into the sea at its warming edges.
* Gulf Stream: few scientists believe it could be switched off completely this century but its collapse is a possibility.
* El NiƱo: the southern Pacific current may be affected by warmer seas, resulting in far-reaching climate change.
* Indian monsoon: relies on temperature difference between land and sea, which could be tipped off-balance by pollutants that cause localized cooling.
* West African monsoon: in the past it has changed, causing the greening of the Sahara, but in the future it could cause droughts.
* Amazon rainforest: a warmer world and further deforestation may cause a collapse of the rain supporting this ecosystem.
* Boreal forests: cold-adapted trees of Siberia and Canada are dying as temperatures rise.

Monday, February 4, 2008

Booby Traps and Tipping Points

The 2007 Time Magazine book on global warming was one of the best all round features on the issues I have seen to date. We all tend to think of natural history moving at small, incremental, and glacially-slow speeds, but recent revelations suggest otherwise. This quote has stuck with me:

"Global climate systems are booby-trapped with tipping points and feedback loops, thresholds past which the slow creep of environmental decay gives way to sudden and self-perpetuating collapse." 2007 Time Magazine special edition on global warming.