The world has taken an important step toward controlling climate change by agreeing to the Bali Action Plan at the global negotiations in Indonesia earlier this month. The plan may not look like much, since it basically committed the world to more talking rather than specific actions, but I am optimistic for three reasons.

The world was sufficiently united that it forced the United States to end its intransigence. The road map marks a sensible balance of considerations. And, realistic solutions are possible, which will allow the world to combine economic development and control of greenhouse gases.
 

The first step at Bali was to break the deadlock that has crippled the global response to climate change since the signing of the Kyoto Protocol a decade ago. This time the world united, even booing the US lead negotiator until she reversed position and agreed to sign the Bali Action Plan.
 

Likewise, the unwillingness of major developing countries such as China and India to sign on to a plan also seems to be ending, though considerable work remains to craft a global agreement to which both rich and poor countries can agree.
 

Doing so requires balancing many concerns.
 

We must stabilize greenhouse gases in order to avoid dangerous human interference in the climate system, the key goal of the 1992 United Nations Framework Convention on Climate Change, the global treaty under which the Bali negotiations took place. We must accomplish this while leaving room for continued rapid economic development and poverty reduction. Poor countries do not and will not accept a system of climate control that condemns them to continued poverty. We must also help countries adapt to the climate change that is already occurring and that will intensify in the future.
 

The Bali Action Plan addresses all three concerns. The plan's main point is to establish an Ad Hoc Working Group to reach a detailed global agreement by 2009 that will set "measurable, reportable, and verifiable" commitments to reduce greenhouse-gas emissions. Such commitments are to be taken in the context of "sustainable development", meaning that "economic and social development and poverty reduction are global priorities".
 

The plan also calls for knowledge transfer to enable poor countries to adopt environmentally sound technologies.

The great question, of course, is whether stabilisation of greenhouse gases, continued economic development, and adaptation to climate change can be achieved simultaneously. Using our current technologies, no; but if we develop and rapidly adopt new technologies that are within our scientific reach, yes.
 

The most important challenge is to reduce, and eventually nearly eliminate, carbon dioxide emissions from burning fossil fuels such as oil, natural gas, and coal. These fuels are at the core of the modern world economy, supplying around four-fifths of the world's commercial energy. Such emissions can be eliminated by either shifting to renewable forms of energy or reducing the emissions from fossil fuels.

The key insight is that roughly 75pc of our fossil fuel use goes for just a few purposes: to produce electricity and heat at power plants, to drive automobiles, to heat buildings, and to power a few key industries such as refineries, petrochemicals, cement, and steel. We need new environmentally sound technologies in each of these sectors.

For example, power plants can adopt solar energy or capture and safely dispose of the carbon dioxide they produce with fossil fuels as can large factories. Automobiles can be engineered for much greater mileage through hybrid technology combining battery power and gasoline. Buildings can reduce their heating needs through improved insulation, or by converting from heating oil to electricity produced by clean technology.
 

According to the best economic and engineering estimates, if each key economic sector develops and adopts environmentally sound technologies in the coming decades, the world will be able to reduce carbon emissions dramatically for less than one per cent of annual global income, thereby avoiding long-term damage that would cost far more. The world can combine economic growth with declining emissions of carbon dioxide. And rich countries will be able to afford to help poor countries pay for the new, cleaner technologies.

To reach agreement by 2009, we must move beyond current generalities by which rich and poor countries argue about who should be blamed for climate change and who should pay the costs. We will need a true global business plan that spells out how the new technologies are developed, tested, and adopted on an expedited basis worldwide.

We must ensure that all countries adopt a verifiable strategy for environmentally sound technology, and that rich countries fulfill the Bali Action Plan's promise to provide "financial and other incentives" to enable poor countries to adopt the new technologies.

With so many crises afflicting our world, there is perhaps cynicism that yet another global conference did little more than promise to continue talking. But let's see the positive message instead: 190 countries agreed on a sensible plan, and the underlying science and technology gives us realistic hopes for achieving it.

There is considerable and difficult work ahead, but the situation is better as a result of the deliberations in Bali. Now it is time to role up our sleeves and achieve what we have promised.