Appendix A: Climate Change Is Accelerating
Coal, oil and natural gas were formed over millions of years by heating and compressing organic materials. Burning these fuels releases their stored carbon as carbon dioxide, a greenhouse gas which traps heat in the atmosphere. Since the start of the Industrial Revolution, atmospheric concentrations of carbon dioxide have risen sharply. Antarctic ice cores of the past 900,000 years show that current carbon dioxide and methane concentrations are 30% and 130% higher, respectively, and the rate of increase 200 times higher than previously recorded. [1] Hundreds of scientists collaborating on the UN Intergovernmental Panel on Climate Change (IPCC) have concluded that humans are responsible for climate change and that its effects will be increasingly severe. [2]
Climate change will cause more variable, erratic and violent weather, including more and stronger hurricanes, such as the record 28 tropical storms and Atlantic hurricanes of 2005, including three Category 5 hurricanes. The damage to Gulf Coast oil and natural gas infrastructure will likely be repeated. [3] Rising sea levels, flooding, storms and droughts could displace hundreds of millions of people and according to a British government study, will annually cost between 5 and 20% of global gross domestic product. [4]
New York City is vulnerable to temporary flooding from storm surges, which will be worsened by rising sea levels as glaciers melt. [5] It is second to Miami as the US city most vulnerable to economic damage from hurricanes. [6]
A selection of online animations vividly portray projected flooding in New York City, Miami, Boston and Washington, DC. [7] Al Gore’s documentary “An Inconvenient Truth" depicts the consequences of climate change as well.
Debate now centers on when a tipping point of irreparable harm will be reached and how deeply emissions must be cut. Until recently, many scientists thought that 450 parts per million (ppm) of carbon dioxide was the limit for avoiding catastrophic climate change. [8] Before the Industrial Revolution, atmospheric carbon was at around 275 ppm, and we’re now at about 383 ppm. [9]
The IPCC conservatively assumes linear progression of climate change and does not include potential acceleration due to feedback loops.
Current evidence shows that climate change is happening much faster than originally predicted, and many climate scientists say the IPCC recommendations are too cautious:"The IPCC suffers from a scientific reticence and in many key areas the IPCC process has been so deficient as to be an unreliable and dangerously misleading basis for policy-making." [10]
Between 1979 and 2005, the rate of Arctic ice retreat had averaged 7% per decade; in the last two years that rate increased to more than 20%. This year Arctic ice shrank to a minimum of 4.13 million square kilometers, compared to the previous record low in 2005 of 5.32 million square kilometers – an expanse of ice roughly the size of Texas and California combined. In spring 2007, the IPCC report estimated the Arctic ice might disappear in the summers as early as 2050 but more likely towards the very end of this century. Just months later, glaciologists were saying it could be as early as 2013 - nearly a century ahead of those IPCC predictions.
To limit global warming to 2 degrees centigrade, many environmental and climate change organizations advocate for reduction of 60 to 80% of our current carbon emissions by 2050. [11] This is an important initial goal. However, America's leading climatologist, Professor James Hansen, Director of the NASA-Goddard Institute of Space Science, says that carbon dioxide levels are already in the danger zone. He estimates that the tipping point for many parts of the climate is around 300 to 350 ppm - well below current levels – so we need to not only eliminate current greenhouse gas emissions, but to remove carbon from the atmosphere to cool down the planet. [12]
Carbon Equity also disputes the widely promoted 2ºC target cap as too high, saying that degree of increase initiates feedbacks that would take the earth past significant tipping points. The proposed 60% cut on 1990 levels by 2050 in the developed world implies a 3°C temperature increase. The last time temperatures were that high, the northern hemisphere was free of glaciers and ice sheets and sea levels were 25 meters higher. A safer target would be a rise of only 0.5ºC and a greenhouse gas level of 320 ppm carbon dioxide equivalent. "There is no ideal achievement timetable other than as fast as possible." [13] The Earth Policy Institute says that the 80% reduction must take place by 2020, not by 2050. [14]
The IPCC’s final report says the world must reverse growth of greenhouse gas emissions by 2015 to avert global climate disaster. Said IPCC head Rajendra Pachauri:"If there’s no action before 2012, that’s too late. What we do in the next two to three years will determine our future. This is the defining moment." [15]
References
1. “Surface Temperature Reconstructions for the Last 2,000 Years,” Committee on Surface Temperature Reconstructions for the Last 2,000 Year, National Research Council, 2006http://www8.nationalacademies.org/onpinews/newsitem.aspx?RecordID=11676; “CO2 ‘Highest for 650,000 Years,’” BBC, Nov. 24, 2005, http://news.bbc.co.uk/1/hi/sci/tech/4467420.stm
2. Intergovernmental Panel on Climate Change, http://www.ipcc.ch/; "Global warming and energy," Sierra Club, http://www.sierraclub.org/globalwarming/, US EPA, http://epa.gov/climatechange/index.html
3. “Is global warming affecting hurricanes?” University Corporation for Atmospheric Research,http://www.ucar.edu/news/backgrounders/hurricanes.jsp;
“Global warming, not just heat wave,” InterPress Service, July 21, 2006,http://www.commondreams.org/headlines06/0721-06.htm
4. “UK Report: Warming Will Damage Economy,” Oct. 30, 2006, Washington Post,http://www.washingtonpost.com/wp-dyn/content/article/2006/10/30/AR2006103000361.html; “Stern Review Report on the Economics of Climate Change,” Oct. 2006, HM Treasury, http://www.hm-treasury.gov.uk./independent_reviews/stern_review_economics_climate_change/stern_review_report.cfm
5. “NASA Looks at Sea Level Rise, Hurricane Risks to NYC,” NASA, Oct. 24, 2006,http://www.nasa.gov/mission_pages/hurricanes/archives/2006/sealevel_nyc.html
6. “Powerful Hurricanes and Northeasters: Threat to the Big Apple,” The Climate Institute,http://www.climate.org/topics/weather/new_york_severe_storm_threat.shtml
7. Global warming animation - NYC, The Pew Charitable Trusts,http://www.pewtrusts.org/news_room_ektid29644.aspx; “Climate Change Information Resources, New York Metropolitan Region,” Columbia University, http://ccir.ciesin.columbia.edu/nyc/index.html;
An Inconvenient Truth, http://www.climatecrisis.net
8. "A Target for U.S. Emissions Reductions," Union of Concerned Scientists,http://www.ucsusa.org/global_warming/science/emissionstarget.html; U.S. Climate Action Partnership,http://docs.nrdc.org/globalWarming/glo_07012201A.pdf; NRDC,http://www.nrdc.org/legislation/factsheets/leg_07032601A.pdf
9. “Remember this: 350 parts per million,” Bill McKibben, Washington Post, Dec. 28, 2007;http://www.washingtonpost.com/wp-dyn/content/article/2007/12/27/AR2007122701942.html
10. “The Big Melt: Lessons from the Arctic Summer of 2007,” Carbon Equity, Oct. 2007;http://www.carbonequity.info/docs/arctic.html
11. U.S. Climate Action Network, http://usclimatenetwork.org/; The Heat is On,http://www.heatisonline.org/main.cfm; Focus the Nation, http://www.focusthenation.org/
12. "James Hansen: Significant climate tipping points have been passed,"http://www.carbonequity.info/docs/hansen.html; “Remember this: 350 parts per million,” Bill McKibben, Washington Post, Dec. 28, 2007; http://www.washingtonpost.com/wp-dyn/content/article/2007/12/27/AR2007122701942.html
13. “Climate Code Red ,” Carbon Equity, Feb.. 2008;http://www.carbonequity.info/climatecodered/summary.html; "Target Practice: Where should we aim to prevent dangerous climate change?," Nov. 2007, Carbon Equity,http://www.carbonequity.info/docs/targets.html
14. Plan B.3, Lester Brown, Earth Policy Institute, http://www.earth-policy.org/Books/PB3/Contents.htm
15. “Climate Panel Says Immediate Changes Are Necessary,” NY Times, Nov. 17, 2007,http://www.nytimes.com/2007/11/18/science/earth/18climatenew.html