Environment

Climate tipping points

Climate change won’t be a smooth transition to a warmer world, warns the Tipping Points Report by Allianz and WWF. Twelve regions around the world will be ...
Arctic sea ice floating in the Arctic Ocean. The North Pole is among the world\'s most sensitive .../ Credits: WWF

Things fall apart

We tend to think of climate change like the retreat or growth of a glacier, a slow and steady process, almost imperceptible, but following a fairly predictable, perhaps even manageable path.

That is a mistake, warns the Tipping Points Report published by Allianz and WWF. A global temperature rise of 2°C and one slightly in excess of 2°C can have fundamentally different effects.

Or to put it differently, an avalanche is a lot worse than just heavy snowfall, and it does not happen in slow motion. Pressure builds until a threshold, or tipping point is passed, and catastrophe ensues.

So it is with climate change; a temperature increase ‘slightly in excess of 2°C’ will likely trigger the slow but inevitable death of most of the Amazon rainforest. That would destroy a vital carbon sink and a giant water tap for regional agriculture, hydropower, and drinking.

With global warming a smooth transition into the future is unlikely, says the report. Instead expect step changes as climate tipping points are passed. Economic, social, and political upheaval will likely follow. The impacts on insurers such as Allianz will be profound.
 


Co-author Tim Lenton explains the Tipping Points concept


Sea level rises, unpredictable monsoons in India, Amazon die-back, and the desertification of Southwest North America (California and neighboring states) are the most significant climate change catastrophes we face, according to the report’s authors from the Tyndall Centre for Climate Change Research.

In the Southwestern U.S. the tipping point has probably already been passed. The scientists now predict that levels of aridity last seen in the 1930s Dust Bowl will have become the norm by mid-century.

However, in some cases the report offers reassurance. Permafrost melt in Eastern Siberia could release greenhouse gases CO2 and methane. But it would require an extreme 9 degrees Celsius surface warming for the system to tip. Claims that the release of greenhouse gases trapped in the permafrost will lead to runaway global warming are “grossly exaggerated,” the authors conclude.

Points of no Return?

The phrase ‘tipping point’ describes the concept that “a small change can make a big difference” to a particular part of the Earth’s ecosystem.

Tipping points include cases of abrupt climate change, and slow changes that occur over decades or centuries. Such transitions can be both reversible and irreversible. In some cases, passing the tipping point is barely perceptible, but it still makes an impact on the future.

The term "tipping element" describes those ecosystems that could be forced past a tipping point.

The report focuses on 12 of the most urgent or “policy-relevant” tipping elements where human activity could have a decisive influence on whether a tipping point is passed.

It assesses their current status, where their tipping points lie, what it takes to trigger them, and the likely impacts of passing the tipping points.

The elements fall into three categories:

The report then identifies four sets of risks associated with these elements and the impacts they entail.

  • sea level rise
  • unstable monsoon in India
  • drought in Amazonia
  • drought in Southwest North America

Sea Level Rises

Just one example: Sea level rise as predicted by the Tipping Points study differs largely from the rather conservative findings of the Intergovernmental Panel on Climate Change (IPCC). Melting polar ice sheets, ignored by the IPCC, would make a 0.5 meter rise by 2050 possible, the Tipping Points report finds.

The Greenland ice sheet, for example, contains enough water for up to 7 meters of global sea level rise. With 1 to 4 degrees of global warming above 1980-1999 levels it could tip into irreversible meltdown. While a total meltdown would take several hundred years, half a meter’s worth of melt this century is possible. What is worse, the rise would be bigger locally, hitting the eastern seaboard cities of the United States hardest.

A global half-meter sea level rise would almost double the number of people vulnerable to flooding worldwide, two thirds of them in Asia. It would endanger an extra 3000 billion dollars worth of coastal assets, mostly in China, the U.S., and India. In New York the exposed assets would increase by 23 percent, with major implications for insurers.

12 Major Climate Tippings Points and why Allianz and WWF care



Lessons to Learn

Unfortunately, these realities are virtually absent from policymaking and not well reflected in current mitigation or adaptation policy.

By framing policy on a global scale—the 2°C threshold for example—we forget that regional climate changes may be far more extreme, rapid, and far-reaching in their impacts. We are also too dependent on IPCC Assessment Report projections which have in some cases been made redundant by more recent evidence, the Arctic sea-ice melt being a prime example.

And because there has been no concerted effort to reduce carbon emissions we are almost certain to breach the 2°C threshold this century. The climate change lag effect means that we could already be irrevocably committed to tipping points we don’t even know about yet.

The Tipping Points Report aims to help rectify this global failure of imagination before passing a global tipping point of no return.


Find more information in the ALLIANZ KNOWLEDGE DATABASE!

Delve into our world of knowledge. The Open Knowledge Database offers you insights in the knowledge, skills and experience Allianz has accumulated in over 120 years of business.


Write a Comment



Comments (9)

keerthi kumar: 21.12.2010, 16:10

It is good information, all govt's should take immediate action by educate the people immediately.All countries should come forward to save this earth.

John Toxey: 09.03.2010, 23:57

We are past the tipping point. The Kyoto Emissions Pact was too late in coming. You all have underestimated the rate of the warming. It will be in decades rather than centuries and will continue to excelerate until a new equilibrium is reached.I have been studying the facts for years and your predictions are all off. You have no real clue as to the impact of this warming. You are all whistling in the dark.
No one talks of the possible positive aspects of the warming. Many areas now not warm might be able to sustain agriculture.
Love to you all and realize that there is nothing we can now do to stop or even slow it down.
Sincerely
John Newbern Toxey III

Thilo Kunzemann: 22.02.2010, 11:19

Many thanks for your comment. In fact, oxygen levels in the atmosphere are not increasing, its the CO2 levels that are increasing. This should already answers your question regarding the oxidation of metals.

The increase of CO2 levels will, theoretically, make plants grow faster. Global warming, however, could make certain areas drier, which will again limits growth. Northern latitudes will probably see increased growth and longer growth periods, while regions closer to the equator won't profit because of increased weather extremes (floods, drought).

Harry Nafpliotis: 13.02.2010, 20:35

Assuming that oxygen levels are increasing what would happen to the normal growth of plants,insects and animals? Furthermore,what would happen to the everyday metal- made appliances from overly exposed to increased oxygen levels? The fact remains that we need the present levels of carbon dioxide which in natural balance with oxygen makes possible our existence.

Mackenzie Jones: 26.01.2010, 03:12

This web site has helped me a great deal. I am in grade 8 and am doing a speech on climate chang/global warming/changing water currents/ and the new phenomeon of 2012...these pages are full of intresting information on the El Ninos and La Nina which was great because that is one of the 4 main points in my speech! This was a great web sit, and i only wish this website had information for every topic in the world, that way all my homework and assinments would be done in a flash. Thanks again!

BINAY SANDWAR: 22.12.2009, 08:19

WHY GOVT. IS NOT SERIOUS FOR THIS THREAT OF GLOBAL WARMING? WHY NOT UPGRADED TECHNOLOGY IS USED TO COMBATE THE POLLUTANTS WHICH ARE RESPONSIBLE FOR GLOBAL WARMING & PLANTS WITH OLD TECHNOLOGY ISLOCKED OUT ?

joe samuels: 19.12.2009, 17:58

It is warmer, but no one knows the cause nor is any agreement will do a thing. "Tipping points" are spoken of on this blog as if it is fact when the fact is it is an opinion. It may or may not be correct. But, remember, in 1980, El Nino happened every 7 years. By 1988, that "fact" was found to be false. This guy is reasonable, rational and unbiased. In other words he has the right approach. Everyone should consider this.
http://symonsez.wordpress.com/2009/12/18/we-dont-know-is-better-than-global-warming-global-cooling-or-they-are-wrong/

James Emery: 18.12.2009, 14:48

Carbon tax will slap 3000 dollars of debt on every newborn child in all participating nation states. i've never heard of a tax across multiple nations, or one that taxes the air, the water, and the flow of you're blood, but making people pay the fat man al gore for all of this will somehow change the endless cycle of cyclical consumption, profit is the only motivation behind gore's actions,

Brad Arnold: 27.11.2009, 08:07

Sadly, current climate models dramatically underestimate future abrupt climate change because ecosystem collapse is underestimated:

Leemans and Eickhout (2004) found that adaptive capacity decreases rapidly with an increasing rate of climate change. Their study finds that five percent of all ecosystems cannot adapt more quickly than 0.1 °C per decade over time.
Forests will be among the ecosystems to experience problems first because their ability to migrate to stay within the climate zone they are adapted to is limited. If the rate is 0.3 °C per decade, 15 percent of ecosystems will not be able to adapt. If the rate should exceed 0.4 °C per decade, all ecosystems will be quickly destroyed, opportunistic species will dominate, and the breakdown of biological material will lead to even greater emissions of CO2. This will in turn increase the rate of warming.

Reference: Leemans og Eickhout, 2004, Another reason for concern: regional and global impacts on ecosystems for different levels of climate change, Global Environmental Change 14, 219–228.

By the way, the world is committed to at least 2C of future warming. Here is what Climate Code Red says:
--Human emissions have so far produced a global average temperature increase of 0.8 degree C.
--There is another 0.6 degree C. to come due to "thermal inertia", or lags in the system, taking the total long-term global warming induced by human emissions so far to 1.4 degree C.
--If human total emissions continue as they are to 2030 (and don't increase 60% as projected) this would likely add more than 0.4 degrees C. to the system in the next two decades, taking the long-term effect by 2030 to at least 1.7 degrees C. (A 0.3 degree C. increase is predicted for the period 2004-2014 alone by Smith, Cusack et al, 2007).
--Then add the 0.3 degree C. albedo flip effect from the now imminent loss of the Arctic sea ice, and the rise in the system by 2030 is at least 2 degree. C, assuming very optimistically that emissions don't increase at all above their present annual rate! When we consider the potential permafrost releases and the effect of carbon sinks losing capacity, we are on the road to a hellish future, not for what we will do, but WHAT WE HAVE ALREADY DONE.



Search for related articles



To view this page ensure that Adobe Flash Player version 10.2.0 or greater is installed.