Currently, the IPCC’s worst‐case scenario forecasts are being realized or exceeded, leading to a catastrophic 1000 parts per million of CO2 by end of century. To preserve the planet in a similar state as now, humankind must aim to reduce CO2 levels from the current 385 parts per million to a stabilized target of 350 parts per million.
Carbon sinks are saturating and becoming carbon sources that add rather than absorb greenhouse gases:
Global plant growth is in a decade-long decline (2000-2009) due to climate change-induced stress from drought.(Science, Aug 2010)
The ocean has absorbed so much CO2 that it is acidifying at an alarming rate. (University of Bristol researchers, in Nature Geoscience, 2010)
With just a 2-degree Celsius average global rise, billions of tons of methane could be released from the Arctic, leading to mass extinctions of life.
2. RISING TEMPERATURES
Without drastic action now, a worst-case scenario rise of 4 degrees Celsius, which means spread of deserts, collapse of the Amazon, and massive release of methane and CO2 gases from melted permafrost, will actually be reached as early as 2060, with a catastrophic warming of 5-7 degrees likely by century’s end.(UK Met Office, 2009)
Scientists report that the first eight months of 2010 have been the hottest on record globally. (NASA, 2010)
2010 was also the year when unprecedented heat and high temperatures were recorded in 16 countries, the highest number ever, including Kuwait, Iraq, Saudi Arabia, Chad, Niger, Russia, Myanmar, and Pakistan.
In the past century alone, the temperature has climbed 0.7 degrees Celsius, at a rate 10 times faster than historic norms, due to human causes.
The past ten years have seen the hottest average annual temperatures ever recorded in our planet’s history. (US NASA, 2010)
Without mitigation, much of the USA, for instance, by end of the century would have extreme temperatures of 122 degrees Fahrenheit (50 degrees Celsius). (Geophysical Research Letters paper, 2008)
Pledges made by governments in Copenhagen to reduce greenhouse gases are not enough to avert runaway climate change. They would still lead to a dangerous temperature increase of more than 3 degrees Celsius. (US Massachusetts Institute of Technology (MIT), 2010)
He, G. (2008, July 9). Finding a Safe Level of Carbon Dioxide for the Global Atmosphere: Results of the Tallberg Forum. World Resources Institute. Retrieved January 11, 2011 from http://earthtrends.wri.org/updates/node/320
Zhao, M. and Running, S.W. (2010, August 20). Drought-Induced Reduction in Global Terrestrial Net Primary Production from 2000 Through 2009. Science 329(5994), 940-943 [Electronic version]. Retrieved January 11, 2011 from http://www.sciencemag.org/content/329/5994/940.abstract
Ridgwell A., and Schmidt, D.N. (2010 , February 14). Past constraints on the vulnerability of marine calcifiers to massive carbon dioxide release. Nature Geoscience online. Retrieved January 11, 2011 from Global Warming University of Bristol news website http://www.bris.ac.uk/news/2010/6835.html