Will world leaders who gather in Copenhagen in December 2009 be able to negotiate a successful successor to the Kyoto Protocol of the Climate Change Convention?  Individual countries are starting from very divergent negotiating positions, and success is not assured.  On the other hand, some observers are worried that the US and China, as the two biggest greenhouse gas polluters, will reach some accord outside of this multilateral framework.  Even though there are many scientific and economic unknowns in this area, some of the biggest stumbling blocks appear to be political.  Check out the views of an economist, Jeff Frankel, about the political pieces that must come together for a feasible agreement to be reached.

Another contentious aspect of the debate is recent cap-and-trade legislation in the United States to levy a carbon tariff on imports from countries that do not agree to control their emissions.  Paul Krugman explains why he disagrees with President Obama's opposition to this strategy.  A hard line interpretation of exactly what is meant by failure to control emissions, however, may be a non-starter in reaching concensus internatiionally.  Frankel suggests an approach based on developing nations committing to no increase in their emissions above a business-as-usual trajectory over the next three or four decades, before they reduce their rate of increase.  A snapshot of his analysis is shown below.