BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Tipping Elements in the Earth System - Tim Lenton\, University of 
 East Anglia\, Norwich\, UK
DTSTART:20070813T102000Z
DTEND:20070813T110500Z
UID:TALK7791@talks.cam.ac.uk
CONTACT:Nick Watkins
DESCRIPTION:The term tipping point usually refers to a critical threshold 
 at which a tiny perturbation can qualitatively alter the state and develop
 ment a system. The term tipping element has been introduced to describe la
 rge-scale components of the Earth System that may pass a tipping point. Of
  particular interest are those elements in the climate system that may be 
 tipped by human activities this century and undergo a qualitative change b
 efore the next millennium. We have critically reviewed these potential pol
 icy-relevant tipping elements\, draw- ing on the fast-increasing pertinent
  literature and an international workshop\, in order to compile a master l
 ist and assess where their tipping points lie. For an important subset\, t
 heir sensitivity to global warming and the uncertainties in this are ranke
 d using the results from an expert elicitation exercise. The Greenland Ice
  Sheet emerges as the tipping element with the nearest threshold and the l
 east uncertainty in this. The majority of causal connections identified b
 etween tipping elements are positive where tipping one element encourages 
 tipping another. This raises the alarming possibility of human activities 
 triggering domino dynamics in the climate system. The implications for hum
 an societies and climate policy are profound. In principle\, early warning
  systems could be established to detect the proximity of some tipping poin
 ts\, but in practice the necessary long time-series of high resolution obs
 ervations are lacking.  Recognizing the nonlinearity in damage costs assoc
 iated with passing a tipping point fundamentally alters the minimisation p
 roblem for the combined costs of mitigation and adaptation\, shifting temp
 erature targets accordingly. On the other hand\, the accessibility of cert
 ain tipping points in the socio-economic system may even provide no-regret
  options for triggering the transition to a low carbon economy.\n
LOCATION:Law Faculty\, Cambridge
END:VEVENT
END:VCALENDAR