The IPCC has called for urgent action on climate change [ark], and UN Secretary General Ban calls it the “defining challenge of our age” [ark]. Despite emerging from a consensus driven, political negotiating process; it appears that the “Summary for Policymakers of the Synthesis Report of the IPCC Fourth Assessment Report” issues the strongest climate warnings yet. Here is a good article providing highlights of the 26 page summary report regarding the risk of global warming [ark | news search].

The report states “warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global average sea level… [and] could lead to abrupt or irreversible climate changes [search] and impacts”. Temperatures are projected to rise by 1.1 and 6.4 (2.0 and 11.5 Fahrenheit) this century.

Regarding solutions and their costs, to limit average global temperature rise to 2.0 to 2.4 degrees celsius, emissions of greenhouse gases would have to peak by 2015. The costs of fighting warming will range from 0.06 to 0.12 percent of global gross domestic product (GDP) per year, which represents a loss of GDP by 2030 of less than 3 percent. Regardless, global warming will last for centuries [ark] whatever is done. This is a clarion call to action to save the Earth’s climate. Who will sufficiently respond?