Archive for the ‘Tipping Points’ Category

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Doha climate talks: Island states stand up for ambition

5 December 2012

“We have not seen concrete progress on the issues that are important to ensuring the survival of all our members. How many conferences do we have to endure where we go back to our countries and say, ‘next year we will increase ambition to reduce emissions, next year we will see finance, next year we will save the climate’? No more next years.”

Sai Navoti, lead negotiator for Alliance of Small Island States (AOSIS)

The elephant in the room at the Doha climate talks (COP18) is the cavernous “ambition gap” between the pathetically weak pledges on the table and the rapid emissions cuts urgently required to keep global warming below the 2°C limit agreed by the world’s governments, let alone a truly safe global target.

Last year’s conference in Durban established a process to close the ambition gap, Durban Platform workstream 2, yet in Doha it is being sidelined in favor of competing negotiating streams. The state of those other streams has reached a new low: the Kyoto Protocol is set to lock in meaningless targets for its few remaining participants diluted by endless loopholes, Long-term Cooperative Action has devolved into a system of inadequate voluntary pledges, and Durban Platform workstream 1 will not be implemented until 2020 when it will be far too late. An informal note from the Durban Platform chair suggests Doha’s outcome on ambition could consist entirely of planning future negotiations. Indeed the talks may even be going backwards on ambition, with Russia backing away from its pledge to cut emissions 25% by 2020.

Only the Earth’s most vulnerable countries, the small island states, are exposing the emperor’s lack of clothes. “The science is absolutely clear,” AOSIS said in a recent statement. “If emissions are not lowered immediately, the opportunity to avert the worst impacts of climate change may be irrevocably lost.” AOSIS is calling for Kyoto 2 to end in five, not eight years; for there to be no legal gap between commitment periods; for surplus permits to be severely limited; for access to Kyoto offsets to be restricted to those bound by Kyoto targets; and for more ambitious targets from all parties, especially rich countries. Read the rest of this entry ?

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Arctic sea ice minimum: A planetary emergency

21 September 2012

The news that Arctic sea ice is in meltdown is being treated as merely one news item among many, even though it threatens to set off a chain of tipping points affecting all of humanity and life on Earth. I’m reminded of how the iceberg warnings sent to the Titanic by other ships were interspersed with passenger messages, and the final and most urgent warning was not considered important enough to deliver to the captain. In 1912 it was the presence of Arctic ice that failed to sink in; in 2012 it is the absence thereof; but the lack of needed attention is the same.

After a spectacular melt season, the Arctic sea ice finally appears to have reached its annual minimum on 16 September. In a horrible milestone, the ice extent shrank to just 3.4 million square km, which is three-quarters of a million square km (or 18%) below the 2007 record low broken in late August, and less than half of the 1980s average. (Note that sea ice extent includes areas with only partial ice cover; actual sea ice area got as low as 2.2 million square km.)

Source: International Arctic Research Center

The ice has retreated so far as to make the Arctic Ocean circumnavigable:

Source: National Snow & Ice Data Center (NSIDC) Read the rest of this entry ?

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Arctic sea ice in a death spiral

29 August 2012

Source: International Arctic Research Center

As Australian politicians fiddle with the details of an extremely insufficient climate change policy, I’ve been watching Arctic sea ice news with increasing dismay. Summer sea ice in the Arctic is fast melting away, accelerated by amplifying feedbacks in what has been called a “death spiral”. The disappearance of Arctic summer sea ice is a key tipping point.

Sea ice floats on the ocean surface and is not to be confused with ice sheets on land. Arctic sea ice grows and shrinks seasonally, with an annual minimum in September. This year, eight independent datasets show we’ve already reached record low sea ice cover in the last week or so, with still weeks to go before the annual minimum.

In the IJIS Arctic sea ice extent dataset (pictured above), the previous record was 4.3 million square km on 24 September 2007 (with the 2011 minimum not far behind). This year we’re only up to 29 August, yet extent has already plummeted to 3.9 million square km. As if that’s not astonishing enough, the ice continues to shrink by 100,000 square km per day. Normally at this time of year, melting slows down as the melt season draws to a close – but this time it seems to be still accelerating, which is unprecedented in decades of observations. Nobody can predict what will happen next. Read the rest of this entry ?

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Is Greenland close to a climate tipping point?

25 July 2012

Recent findings suggest climate change in Greenland may be approaching a tipping point, beyond which amplifying feedbacks could lead (probably over centuries) to complete melting of the ice sheet, raising sea level by about 7 meters.

In June, a team of glaciologists led by Jason Box predicted that we would see melting across 100% of the ice sheet’s surface area in summer within a decade. They drew that conclusion from data on the Greenland ice sheet’s surface reflectivity, or “albedo”, showing the surface has gotten darker over the last 12 years. A darker surface absorbs more heat, leading to more melting, causing albedo to decrease further, and so on in a vicious circle.

The ice naturally gets less reflective in summer because the shape of the snowflakes changes, but in 2012 Greenland has become much darker than in previous summers. This is occurring particularly at high elevations, which were previously too cold to melt and indeed had gained ice from increasing snowfall. This month, at the height of the melt season, Greenland’s albedo has fallen far off the charts:


Figure 1: Surface albedo of the Greenland ice sheet (average of all elevations) between March and October in each year from 2000 to 2012. (Source: Ohio State University) Read the rest of this entry ?

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Climate change explained in 15 minutes

5 July 2012

The other day I found this great TED video where blogger David Roberts explains the significance of increasing degrees of global warming:

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Titanic and Global Warming

15 April 2012

After the RMS Titanic’s collision with an iceberg a century ago today, the passengers did not believe the ocean liner would sink. The ship was so gargantuan and stably designed it showed few outward signs of being in imminent danger, and took 2 hours and 40 minutes to sink. But sink it did. The Earth’s climate is rather like the Titanic: an enormous beast that is deceptively stable and slow to respond to disturbances.

(Source: Wikipedia.)

The parallels between global warming and the Titanic disaster begin before the collision, with the failure to heed iceberg warnings. If you’ll forgive me for quoting Wikipedia:

The North Atlantic liners prioritised time-keeping above all other considerations, sticking rigidly to a schedule that would guarantee their arrival at an advertised time. They were constantly driven at close to their full speed, treating hazard warnings as advisories rather than calls to action. It was widely believed that ice posed little risk […] Titanic‘s future captain, Edward Smith, declared in an interview that he could not “imagine any condition which would cause a ship to founder. Modern shipbuilding has gone beyond that.” Read the rest of this entry ?

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Get ready for the carbon bubble

20 February 2012

Remember the sub-prime mortgage bubble? The next economic bubble could be caused by investing in the unsustainable fossil fuel industry. The idea might sound incredible, but it results from our failure to seriously address the science of climate change.

The science tells us we can’t burn all fossil fuels

Fossil fuels formed over millions of years from dead plants that were quickly buried, removing carbon from the atmosphere in the process. Thus fossil fuels contain carbon which has been out of circulation for up to hundreds of millions of years. Yet humans are digging up this carbon and burning it in the space of a few centuries. When carbon (C) is burned, it reacts with oxygen to produce carbon dioxide (CO2), a heat-trapping greenhouse gas.

Carbon dioxide from fossil fuel burning is the main cause of anthropogenic global warming, now far outstripping natural influences on climate. Carbon dioxide in the atmosphere is like radioactive waste: much of it hangs around for a very long time. As long as humanity continues to burn fossil fuels, carbon dioxide will continue to accumulate in the atmosphere and the Earth will continue to warm. The urgent need to prevent further warming leaves us with no choice but to phase out fossil fuels as rapidly as possible.

In the words of NASA climatologist James Hansen, saying what other scientists have generally failed to communicate, “we cannot burn and emit to the atmosphere most of the remaining fossil fuels”. If we wish to avoid unimaginable global catastrophe – or to meet the target the world’s governments have agreed to – let alone to limit global warming to a level anywhere near what scientists consider safe – we must leave the vast majority of the planet’s fossil carbon in the ground. Read the rest of this entry ?