President Obama and United Nations (U.N.) Secretary General Ban Ki-moon saw eye to eye on fighting climate change when they met at the White House yesterday. Ban said that he and Obama agree that climate change is an “existential threat” to mankind, according to a U.N. press release. The leaders have high hopes for when the U.N. convenes in Copenhagen, Denmark, in December to work out a successor to the Kyoto Protocol, the 1992 international climate change treaty that expires in 2012.

Just over 50 days in office now, Obama has made clear his intentions to get the U.S. on better climate footing. Obama wants to institute a carbon cap-and-trade system, such as the one in practice by the European Union since 2005. This regulatory scheme sets a countrywide statutory limit, or “cap,” on greenhouse gas (GHG) emissions. Companies then buy credits from the government that represent their portion of total emissions toward the cap. These credits are then sold amongst companies – the “trade” – creating a GHG credit marketplace. This system allows businesses who lower their emissions to profit from selling their credits to companies that need to up their allotted emissions – or face stiff financial penalties – thereby encouraging emissions-lowering practices.

Beyond cap-and-trade, generous tax breaks for and investment in renewable energy and energy efficiency are already included in the $787 stimulus package signed into law by Obama last month. The president has called for “five million green collar jobs” since the campaign trail, and looks set to encourage whatever practices help wean the U.S. from fossil fuels.

Secretary-General Ban is clearly pleased to see the U.S. step to the fore in promoting climate change awareness and mitigation efforts. Looking ahead to Copenhagen, Ban said: “With U.S. leadership, in partnership of the United Nations, we can and will reach a climate change deal that all nations can embrace,” according to the UN press release.

Image Credit: NASA