Climate change is happening with a rapidity scientists did not predict—the Arctic is melting faster, sea level is rising faster, and Co2 levels are fast approaching the point where the world will not be able to restrict global warming to the 2 degrees Celsius (C) that scientists warn is the threshold above which we face catastrophic consequences. Public consciousness of the climate crisis, although reawakened by the unprecedented droughts, fires and storms of 2012, is not rising fast enough. Most governments, locked in their games of power and profit, give climate change little priority—shoving it aside as a problem to be dealt with sometime in the future. The UN climate talks in Doha, Qatar ended with an abysmally weak agreement by the EU member states, and a few others, to extend the Kyoto Protocol for an additional seven years. The United States, Japan, Canada, Russia, and China are not taking part. But our time for action is running out. For years, Jim Hansen, the world’s foremost climate scientist, has warned that we have a narrow window of opportunity—ten years or less—to drastically reduce our use of fossil fuels and halt anthropogenic climate change before dangerous tipping points are reached.
Arctic Warming
Arctic sea ice extent shrank 18% to a new low this year from the previous low set in 2007. Along with the record loss of sea ice, the thickness, or volume of the remaining ice has been significantly decreasing. Scientists from the National Snow and Ice Data Center in Boulder, Colorado said the data suggests the Arctic sea ice cover is fundamentally changing. “We are now in unchartered territory, said NSIDC director Mark Serreze. “While we’ve long known that as the planet warms up, changes would be seen first and most pronounced in the Arctic, few of us were prepared for how rapidly the changes would actually occur.” Ice scientist Prof Peter Wadhams of Cambridge University predicts that the collapse of the Arctic ice sheet has begun and will probably be complete by 2015, 2016. Sea ice in the Arctic is an important indicator of global warming, because of its role in amplifying climate change. When the ice collapses, the sun is no longer reflected from the surface, but is absorbed into the ocean, causing more warming and more sea ice collapse (a positive feedback loop). The resulting decrease in temperature gradient between the equator and the Arctic slows the jet stream winds and increases their waviness in the north/south direction. This may shift weather patterns across the Northern Hemisphere. Less ice may weaken and shift the jet stream, causing it to hold storms, dry spells and heat waves in place so that they pound a single location for days, weeks, or months. According to Sam Carana, from the Arctic Methane Emergency Group, warming in the Arctic changed the jet stream, and the altered jet stream was what forced Hurricane Sandy to move inland, to spread out and to hang around for a long time.
Arctic warming is also melting permafrost across Alaska and Siberia faster than models had predicted. Vast areas of permanently frozen ground in Russia, Canada, and Alaska are beginning to thaw, releasing carbon dioxide and methane that has been locked in the subsoil for thousands of years. A report from the UN Environment Programme released for the conference in Doha, warns that warming permafrost could release the equivalent of between 43 and 135 billion tonnes of carbon dioxide by 2100. Thawing permafrost also releases methane, a potent greenhouse gas, which, in the short term, has twenty-five (25) times more impact on temperature than CO2. The release of greenhouse gases from the permafrost is another positive feed-back loop, since they increase warming, which in turn, melts more permafrost and releases more Co2 and methane. Scientists worry that if the Arctic continues warming, methane will escape, not only from thawing terrestrial permafrost but from methane hydrates on shelf margins in the ocean.
Sea Levels
Sea levels worldwide are now about a foot higher than a century ago largely because of global warming. But no one anticipated the rapidity with which sea level has continued to rise. In 2002, the Intergovernmental Panel on Climate Change (IPCC) predicted an annual sea-level rise of less than 2 millimeters per year. But from 1993 through 2006, the oceans actually rose 3.3 millimeters per year, more than 50 percent above that projection. Using satellite imaging, a large group of polar research teams recently concluded that melting of the polar ice sheets has contributed about one-fifth of the overall global sea level rise since 1992; the other major contributor to sea level rise is seawater expansion due to global warming. Supported by US and European space agencies, the research brought together data from satellites measuring the surface altitude, the flow of the glaciers and the gravitational effect of the ice mass to produce the first joint assessment of how the ice sheets are changing. Although East Antarctica has gained mass over the study period of 1992-2011 as increased snow fall has added to its volume, Greenland, West Antarctica and the Antarctic Peninsula have lost mass—and on a scale that more than compensates for East Antarctica’s gain.
After Hurricane Sandy, the National Oceanic and Atmospheric Administration (NOAA) warned that sea levels will continue to rise. NOAA sees a greater than 90% chance that global mean sea level will rise at least 8 inches (0.2meters) but less than 6.6 feet (2.0 meters) by 2100. Most climate scientists, including Rahmstorf and Caldeira, have been convinced for several years that the increase in sea level by the end of the century will be more than 3 feet (assuming that no serious measures are taken to reduce heat-trapping greenhouse gas emissions.) James Hansen is the leading spokesperson for the view that the ice sheets in Greenland and parts of Antarctica are unstable and may break down in a rapid non-linear manner in global warming conditions, causing very large levels of twenty-first century sea level rise. Rapid non-linear ice sheet disintegration has happened in past warming periods. About 14,000 years ago, sea level rose about 20 m in approximately 400 years—an average of 1 m of sea level rise every 20 years. Hansen describes the glacier disintegration required for delivery of that much water from the ice sheets as “explosive.” Although Hansen’s view is the minority view at this time, there is not enough data to disprove it.
Future sea-level rise, like the recent rise, is not expected to be globally uniform—some regions will have a sea-level rise substantially more than the global average (in many cases more than twice the average), and others a sea level fall. Whatever the rate of sea level rise, it could cause catastrophic difficulties for shore-based communities, including major cities, like London, New Orleans and New York. A sea level rise of just 200 mm could create 740,000 homeless people in Nigeria, the Maldives, Tuvalu and other low-lying countries. The UN’s environmental panel has warned that, at current rates, sea level would be high enough to make the Maldives uninhabitable by 2100.
Greenhouse Gas Emissions
By far the most troubling data to be released recently though, comes from several studies which show continued increases in carbon dioxide (CO2) emissions, and cumulative greenhouse gas levels in the atmosphere that makes it very likely the world will go past the 2 degree C warming threshold into dangerous climate chaos. According to a study published Dec. 2, 2012 in the journal Nature Climate Change, carbon dioxide emissions will rise by 2.6 percent this year, fueled by major increases in China and India. Global emissions jumped 58% between 1990 and 2012. If our current emissions trajectory is not halted, the world faces warming between 4C and 6C by the end of the century. “The risks of dangerous climate change are too high on our current emissions trajectory. We need a radical plan,” said co-author Corinne Le Quere, director of the Tyndall Centre for Climate Change Research in Britain.
The World Meteorological Organization (WMO) takes accurate measurements in more than fifty countries of the greenhouse gas concentrations now in the atmosphere. The measurements show the levels of carbon dioxide, methane, and nitrous oxide remaining in the atmosphere after about half of the CO2 is absorbed by the oceans and stored in tropical forests. Methane emissions only remain in the atmosphere for an average of 8.4 years, in contrast to CO2 emissions, which remain in the atmosphere for hundreds of years. The cumulative level of greenhouse gases in the atmosphere reached a new record high in 2011, as reported in WMO’s Greenhouse Gas Bulletin. “These billions of tons of additional carbon dioxide in our atmosphere will remain there for centuries, causing our planet to warm further and impacting on all aspects of life on earth,” said WMO Secretary-General Michel Jarraud. “Future emissions will only compound the situation.”
The fact that we are on course for a 4-degree world was recently emphasized by the World Bank, a relatively recent convert to the urgency of climate change, that still needs to match its actions with its words. The Potsdam Institute for Climate Impact Research and Climate Analytics wrote the report for the World Bank, concluding that the climate could warm from the current global mean temperature of 0.8C above pre-industrial levels, to as high as 4C by 2100, even if countries fulfill current emissions-reduction pledges. If we hit 4 degrees Celsius warming we will have “extreme heat-waves, declining global food stocks, loss of ecosystems and biodiversity, and life-threatening sea level rise.”
The bleakest assessment, the brutal climate facts, comes from Kevin Anderson, a leading scientist with the Tyndall Centre for Climate Change Research and a climate advisor to the British Government. In a 2011 paper co-authored with Alice Bows, Anderson shows that climate scientists themselves are underplaying the consequences of climate change. Anderson says that the commonly accepted threshold of climate “safety,” 2 degrees C [3.6 degrees F] temperature rise over pre-industrial levels, is now properly considered extremely dangerous and even 2 degrees C is drifting out of reach, absent efforts of a scale and speed beyond anything currently proposed. Yet the climate scenarios and plans offered to policymakers do not actually reflect that threshold. For example, most popular climate scenarios include an implausibly early peak in global emissions- 2015-16 in the Stern Report, the ADAM project and the UK’s Committee on Climate Change. Why do climate scientists present plans that contain such wildly optimistic assumptions? According to Anderson, it is because emissions reductions of 3 to 4 percent a year are the maximum compatible with continued economic growth, —so that’s the level many climate scientists use in their scenarios. Yet reductions at that pace offer little practical hope of avoiding a temperature rise below 2 degrees C.
There is a widespread view that a 4 degree future is incompatible with an organized global community, is likely to go beyond “adaptation”, is devastating to the majority of ecosystems, and has a high probability of being unstable. Said Anderson, “Our current trajectory is leading us toward 4 or 6 (or 8 or 10) degrees C, which we now know to be a potentially civilization-threatening disaster. For humanity, it’s a matter of life or death.” He continued,“We will not make all human beings extinct as a few people with the right sort of resources may put themselves in the right parts of the world and survive. But I think it’s extremely unlikely that we wouldn’t have mass death at 4C. If you have got a population of nine billion by 2050 and you hit 4C, 5C, or 6C, you might have half a billion people surviving.”
What Can We Do?
James Hansen suggests that we put a price on carbon. The cost of fossil fuels is artificially low because it does not include the price they incur on society, through air and water pollution and the effects of global warming. His solution is a gradually rising fee attached to all fossil fuels at their mine or port of entry. The fee would then be redistributed to the public. A rising cost on greenhouse gas-producing fossil fuels would spur investment in clean alternatives.
Bill McKibben has made it clear that we must leave most of the world’s remaining inventory of fossil fuels in the ground. In an important article published in Rolling Stone last summer, he sets out the terrifying new math. The first number is 2 degrees C, the number scientists warn we must stay under to avoid climate catastrophe, the second number is 565 gigatons—the amount of carbon we can still burn and have a chance of staying below two degrees. At current rates of emission, it would take us about 15 years to get there. Much worse is the third number: 2,800 gigatons, – that is how much the fossil fuel industry and the countries that operate like fossil fuel companies already have in their reserves. To have any hope of avoiding climate chaos, we must leave four-fifths of that in the ground. The current campaigns—to prevent coal export in the Pacific Northwest, to stop mountaintop removal in Appalachia, and to halt the Keystone XL pipeline—are attempts to keep dirty coal and dirty tar sands oil out of the market.
But what would it take, Anderson asks, to target 2 degrees C realistically? We would have to stop lumping together the changes that the developed nations and still developing countries need to make. Although China currently emits more than the US on an absolute basis, historically the developed countries have emitted far, far more carbon. And they’ve benefited by becoming extraordinarily wealthy. Developing countries, by contrast, have spent far less and are still busy bringing millions of people out of abject poverty. So the developing countries should get more of the world’s carbon budget for the century.
Anderson offers the following example: if global emissions must peak by 2020 to have any chance of avoiding dangerous climate change, there is no way China and the other developing countries will be able to peak their emissions by then. We need to give them until 2025 to peak (which is at the very outer edge of the realm of the possible). If that is true, developed countries must compensate by peaking before 2015 (a mere two years from now). What would it mean for the US and other developed countries to peak their emissions in 2015 and decline them by 10 percent a year thereafter? “No carbon tax is going to do that. We won’t get there through innovation or new technology, even if we spend a trillion a year for the next few years. The only conceivable way to produce that level of reductions,” says Anderson, “is a full-scale, all-hands-on deck mobilization, what William James called ‘the moral equivalent of war.’”
This is the stark conclusion drawn by Anderson and Bows: “The logic of such studies suggests extremely dangerous climate change can only be avoided if economic growth is exchanged, at least temporarily, for a period of planned austerity within the developed nations and a rapid transition away from fossil-fueled development within the developing nations.” David Roberts has written three articles in Grist about the Anderson-Bows paper. All three are worth reading. The first can be found on Grist.org here.
Bourtai Hargrove is a grandmother, a retired lawyer, and an activist with Olympia FOR’s climate group, Confronting the Climate Crisis.
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