As the last United Nations conference on climate change before the expiry of the Kyoto Protocol in 2012, the ongoing conference in Durban, South Africa, bears people's hopes that all world members will uphold their responsibilities for reducing greenhouse gas (GHG) emissions.

However, a new global economic recession since the onset of this year, the high unemployment rate in the United States, the increased risk of the collapse of the euro amid the deteriorating debt crisis in some eurozone countries and political unrest across the world, have cast a long shadow over the prospects of the Durban meeting.

The key to success at the Durban conference lies in whether or not participating countries can reach an agreement on a second commitment period of the outgoing Kyoto Protocol. This will lay the groundwork for any international talks on climate change. Otherwise, any meaningful action on emissions reduction will be out of the question. Failing to agree a second commitment period will be the equivalent of discarding the Kyoto Protocol and will produce significant adverse long-term effects on any international talks on climate change.

So far, a majority of Annex 1 countries - mainly industrialized countries - have failed to fully fulfill their emission reduction commitments as demanded by the first commitment period of the protocol. In this context, the failure to reach a deal on the second commitment period will result in the absence of a legally binding document that commits all parties to continue to fulfill their unfinished commitments in the years ahead.

The Durban conference should also try to take substantial steps towards guaranteeing funds to help impoverished countries deal with climate change, transform their economic growth modes and embark on a low-carbon and green development path. Developing countries have stressed many times that they need a growing amount of funds every year to press ahead with these. Developed countries should also make some institutional arrangements to help small and impoverished nations which lack enough political, economic and systematic capacity, to follow a low-carbon and green development path.

In recent years, developed countries have raised their calls for developing countries to undertake a bigger role in the reduction of global GHG emissions. Data shows that in 1990, industrialized nations accounted for more than 70 percent of the globe's GHG emissions, but their proportion had declined to 50 percent by 2010. The developing countries' proportion of global GHG emissions is expected to increase to 70 percent somewhere between 2040 and 2050. However, the increased proportion of emissions by developing countries will not change the fact that their per capita emission volume is still far below that of their developed counterparts.

So far, major developing countries such as China, India, Brazil and South Africa have formulated their own programs for further emission reductions, in sharp contrast with some developed countries' defiance of basic international norms on climate change and their stubborn calls for less-developed countries to undertake bigger international responsibilities incommensurate to their development status.

It is developing countries' stance that all countries should comply with the UN Framework Convention on Climate Change and use this legally binding document to regulate their activities under the principle of "common but differentiated responsibilities".

A variety of uncertainties suggest that there is not much possibility of a legally binding treaty being reached that will commit developed countries to undertaking more responsibilities for GHG emissions reduction. The probability is that a non-legally binding document will be signed at the Durban conference, just like the one agreed at the Copenhagen Conference, while leaving all the key issues pending to the next meeting.

The author is a senior climate change and energy consultant to the Natural Resources Defense Council, a New York-based environment group.