EGU Assembly 2013
Presentation by Dr Peter Carter
Vienna AGU "Sustainability transitions of the socio-ecologic system"
Topic Global change processes cause a large challenge for society. Significant changes in some of our current ways of living are necessary in order to not transgress important natural boundaries. For example, CO2 emissions need to be drastically reduced to avoid severe effects from climate change. These changes in society are likely to cause an overall transition of the socio-ecological system.
Is the World in a State of Climate Change Planetary Emergency?
Leading climate change experts have made public statements that the world is beyond dangerous interference with the climate system, committed to a warming of 3-5ºC, facing a risk of global climate catastrophe, and in a state of planetary emergency, but these conclusions are not informing climate change policy. The evidence for these statements is examined and presented in this paper. The main parameters considered are world food security and carbon feedback "runaway" or rapid global warming. 2012 was a record year for Arctic albedo loss, which amplifies Arctic warming and drives Arctic methane feedback emissions. Since 2007, atmospheric methane is experiencing a renewed, sustained increase due to feedback emissions. All potentially large positive Arctic feedbacks are operant. These include albedo loss from disappearing snow and summer sea ice; methane released from peatlands, thawing permafrost and sea floor methane hydrates; and nitrous oxide from cryoperturbed permafrost. Increasing extreme weather events have caused regional crop productivity losses on many continents since 2000. The loss of Arctic albedo might be driving extreme heat and drought in the northern hemisphere. Today the formal national pledges for emissions reductions filed with the UN, combined, commit humanity to a warming of 4.4ºC (Climate Interactive) by 2100, which is more than 8ºC eventually after 2100, and there are no initiatives to change this. The International Energy Agency warns that the current global economy is on track for a warming of 6ºC by 2100. A simple yet novel summation approach of all unavoidable sources of warming estimates the committed unavoidable warming to be 3ºC by 2100. What are the implications of these future commitments for world food security and the risk of runaway climate change? The paper considers how these commitments and the policy-relevant research findings can inform policy making with respect to an appropriate science-based mitigation response.
The evidence from observed extreme impacts, trends and projections affecting all regions is now so overwhelming that it is clear we all live in state of committed global climate disruption emergency.
The Arctic is undergoing extremely rapid (if not abrupt) change.
It is now warming three times faster than the rest of the planet.
The Arctic summer sea ice passed its ice- free summer tipping point in 2007 and is now under a heading to start being summer sea ice free, in as soon as a few years.
The loss of Arctic summer sea ice albedo cooling, and also the loss of far North snow albedo, is a very large positive climate system feedback with catastrophic implications.
This has already triggered the Arctic to emit all three greenhouse gases, mainly methane but also carbon dioxide and nitrous oxide, from all (previously safe) sources of Arctic methane.
Because there are no negative feedbacks to stop this multiple cascading positive feedback process, without an emergency intervention this will lead to a progressive increase in the heating of the Arctic and the Northern Hemisphere and will further accelerate global warming. This makes standard ideas about mitigation or adaption inadequate.
The loss of Arctic albedo cooling is bound to adversely affect the world's prime agricultural regions in the normally temperate Northern Hemisphere.
There is an increase in extreme heat and drought affecting the Northern Hemisphere and therefore it is possible that this effect is already happening.
The stabilization of the Arctic summer sea ice and Northern Hemisphere snow cover, with the stabilization of Arctic carbon and the temperate Northern hemisphere climate, is our most urgent imperative.
CLIMATE EMERGENCY INSTITUTE
The health and human rights approach to climate change