The next United Nations-sponsored global climate change conference is scheduled for Paris at year end.

WASHINGTON — The next United Nations-sponsored global climate change conference is scheduled for Paris at year end. Prospects for some agreements on collective actions are much improved over the failed outcome of the Copenhagen summit two years ago. A variety of factors are at work in altering this prospect.

Perhaps most important is a shift in approach. The Kyoto Treaty that the United States rejected and the failed attempts at negotiating a successor all tried to dictate goals and actions for developed countries, with little or nothing to be done by developing countries. In the run up to the Paris conference the focus has shifted to what countries are voluntarily willing to undertake (so-called Intended Nationally-Determined Commitments, or INDCs). Critical steps in this direction were taken by China and the United States earlier this year.

The Obama administration proposed a “Clean Power Plan” in August designed to lower carbon emissions from power plants by 2030 to a level nearly one-third lower than in 2005. Chinese leaders have committed to achieve a ceiling in greenhouse gas (G.H.G.) emissions by 2030 if not earlier and to implement a carbon-trading scheme in the next few years. Altogether, nearly 150 countries have submitted plans. An approach built on pledges voluntarily undertaken by governments seems to be creating momentum where negotiated dictates could not.

A second factor beyond the shift from demands to offers has been the growing recognition of the need for action by developing countries in addressing G.H.G. emissions. A decade ago, U.S. emissions were the largest in the world. They seem to have peaked around 2007 at 5.5 billion tons of CO2 per year and are receding. Meanwhile, China’s CO2 emissions have soared past those of the United States, reaching 9.5 billion tons by 2012 and still rising. And while Indian emissions were only around 2 billion tons in 2012, its economic growth trajectory could lead it past the United States to become the second largest emitter by 2030. On a smaller scale, similar patterns are likely in other developing countries. This makes it ever more important that mitigation strategies go beyond what the
developed world must do and engage developing countries in dialogue about what they can and will do.

A third factor contributing to this shift in prospects is a greater focus on the benefits measured by non-climate-change factors — what some call a “no regrets” approach. There are many opportunities being identified here. For example, preventing methane emissions from mines, wells and pipelines is justified by their savings in energy otherwise lost. Cutting methane emissions by one-third, however, also has a significant climate change benefit, since methane gas disappears from the atmosphere more quickly than CO2.

Black soot — emissions from dirty diesel engines, cooking stoves and wild fires — is another area of potentially quick gains. Cutting this emission source through better technologies, cooking stoves and heating fuels may speed economic development and sharply reduce deaths and disabilities from toxic indoor and outdoor air. Those immediate benefits more than justify related costs, but there also will be a climate change benefit from a resulting slower melting of glacial
ice and snow.

The developing world also is experiencing the largest and fastest migration from rural to urban areas in human history. Building future cities smartly with energy-efficient buildings and transportation systems may save these countries trillions of dollars in construction outlays while also giving them a lower energy-resource intensity in their economic development growth paths.

On the agricultural front, research has revealed the high G.H.G. emissions arising from conversion of virgin forests to agricultural uses. This has given new impetus to food strategies built around “sustainable intensification” — using good lands already in production more efficiently while restoring marginal lands to better condition.

Several food industry leaders have signed a pledge to pursue more sustainable supply chains, promising to “talk transparently about our efforts and share our best practices so that other companies and other industries are encouraged to join us in this critically important work.” They also have pledged to urge political leaders to pursue “clear, achievable, measurable and enforceable science-based targets for carbon emissions reductions.” The focus in both cases is on cost-effective strategies, not high-cost, feel-good actions.

All of this seems to suggest that the Paris conference this December may usher in a more mature dialogue about climate change related activities. Of course, there will be demands from some to do more. One estimate is that the voluntary plans will yield a 7% reduction in G.H.G. emissions by 2030 from a “business-as-usual” course while something closer to a 30% reduction is what is called for. Nevertheless, this new strategy looks to be off to a promising start.