DURBAN, South Africa—When roughly 25,000 people descend on a city to talk climate change, you can expect at least two things: mountains of waste and copious emissions of the greenhouse gases that they've come to talk about so seriously. To offset the hundreds of thousands of tons of these lightweight gases emitted in the pursuit of a global climate treaty, recent such conferences have taken compensatory measures, such as subsidizing retrofits of Bangladeshi brick factories, so that ambassadorial emissions are offset by a reduction in pollution from kilns.

Here in eThekweni municipality the local utility may have a small wind turbine spinning briskly on the roof of its headquarters, but the bulk of the power comes from coal, and the smell of smoke is evident except in those locales cleansed by sea breezes. In fact, 99 percent of the power here comes from burning fossil fuels, whether for electricity or transport. Yet, the municipality spent some $715,000 to ensure the greenhouse gas emissions of this conference are eventually tabulated—and accounted for rigorously.

The idea then is to offset the surplus CO2 by investing locally in emission reductions: There are free bikes for delegates (as well as free buses running on diesel partially made from coal). There is tree planting in Paradise Valley ("alien species" of trees are removed and replaced with "locally indigenous" varieties). And there is a 500-kilowatt (at peak sunlight) concentrated solar-photovoltaic array from France-based Soitec Solar—the largest in all of South Africa—in nearby Verulam (as well as one showcase array outside the conference itself). Finally, the U.N. Framework Convention on Climate Change's 767 staff members offset their emissions by investing in CO2-reduction credits generated by switching a coal-fired brick kiln in Johannesburg to natural gas.

Of course, the primary source of emissions from those of us in attendance are all those flights into and out of Durban and other locations in South Africa. It doesn't help that some of that jet fuel is actually made from coal here, and a limited amount of offsets isn't going to help that. Plus, there's the cumulative total of what have now been 17 official conferences of the parties and innumerable side-event negotiations—all to produce, thus far, the limited reductions achieved under the Kyoto Protocol, which have been more than offset by the growth in emissions from some developed and many developing countries.

Then there's all the food. In Copenhagen two years ago, some 45,000 people consumed 300 metric tons of food—beef, poultry, fish, fruit and vegetables, but also hot dogs and pastries (as well as more than 250,000 cups of coffee, according to the official press release). Outside this conference, vegans hand out sandwiches and proclaim "no animal died for this," but it remains to be seen how much Durban's contingent consumes—and how much the agricultural practices to produce all that food contributed to greenhouse gas emissions, either directly through, for example, emissions from fertilizer production or via land clearing for farming.

In the end, the only justification for all this consumption and emissions is a global treaty to reduce greenhouse gases and forestall catastrophic climate change. As it stands now, the negotiators are haggling over whether to "launch a process in order to develop a legal framework applicable to all [nations] under the United Nations Framework Convention on Climate Change after 2020," and to be completed no later than 2015. Such a treaty would go a lot further than planting some trees or burning natural gas instead of coal.

Bicycles in racks at climate talks in Durban

Images: David Biello