RIO DE JANEIRO - Once again, humanity is facing the risk of catastrophe. The terror of destruction by nuclear missiles ready to be launched at the touch of a button has given way to the disturbing possibility of global warming going past the point of no return, and this is turning traditional international coalitions and geopolitical concepts upside down.

Although the seriousness of the threat to human survival has been acknowledged in diplomatic rhetoric, the international powers are still not giving the climate crisis the absolute priority it deserves. The old divisions and disputes arising from strategic, economic, trade and ideological issues continue to predominate.

Brazil, for instance, should join the European Union (EU) in a "virtuous and responsible alliance," and distance itself from China, the country that now emits the greatest volume of greenhouse gases and has an "irresponsible" attitude to climate, Eduardo Viola, a professor of international relations at the University of Brasilia, told IPS.

In the view of this pioneer Brazilian scholar of global climate security, only cooperation between the main greenhouse gas emitters can create the conditions needed to avoid dangerous climate change, which will occur if the average surface temperature of the planet rises by more than two degrees during the course of this century.

An important factor will be whether or not U.S. voters chooses a president in November 2008 who is capable of taking a leadership role in facing this challenge.

Brazil, the sixth largest greenhouse gas emitter after China, the United States, the EU, India and Russia, could contribute to climate-friendly progress by allying itself with European governments and Japan to work for "a transition to a low-carbon economy," assuming major commitments and recovering the degree of environmental leadership it enjoyed in the 1990s, said Viola.

The peculiarity that deforestation accounts for 60 percent of Brazil's greenhouse gases means that this country can reduce emissions at a lower cost than larger emitters, he said.

Brazil's annual emissions were one billion metric tons of carbon dioxide equivalents in 2004, but have already fallen by more than 30 percent, because the rate of deforestation of the Amazon has slowed by more than half over the last three years.

However, the equivocal attitude of the government of Brazilian President Luiz Inácio Lula da Silva prevents it from taking advantage of this result to strengthen its position in climate negotiations, complained Rubens Born, coordinator of the non-governmental Vitae Civilis institute.

"If Brazil were more independent of the Group of 77 (G77) and China, it could make a difference to the future of climate change," Born told IPS.

The G77, now made up of 130 countries, was formed in 1964 to defend the common economic interests of developing nations. But it is dysfunctional with respect to climate issues, because of the presence of China and the petroleum exporting countries, which have conflicting interests with the rest of the group, said the activist.

Born returned with a sense of disappointment from the Dec. 3-15 Conference of the Parties to the United Nations Framework Convention on Climate Change (UNFCCC) in Bali, Indonesia.

Political manoeuvring prevented the adoption of an explicit target for industrialised countries' greenhouse gas emission reductions of 25 to 40 percent by 2020, and relegated the conclusions of the Intergovernmental Panel on Climate Change (IPCC) to a footnote, which "weakened the goal" of the meeting, he said.

(The Nobel Prize-winning panel of 2,500 scientists said in its final report this year that this target range for emissions reductions with respect to 1990 levels is necessary in order to avoid the worst climate catastrophes.)

Some progress was achieved at Bali, such as including steps to protect forests in the Bali "roadmap", the approval of a climate change adaptation fund to help poor countries protect their people against climate disasters, and encouragement for the G77 to take "measurable, communicable and verifiable" national actions for climate change mitigation, even though developing countries are not obliged to do so under the Kyoto Protocol.

However, these outcomes are insufficient to ensure negotiations will progress at the necessary speed, and "we only have two years" to reach a difficult agreement, Born said.

The new reality demands "a different way of grouping countries," based on criteria that differ from the traditional economic or military rationales. Environmental and climate issues must climb to the top of the agenda in national and international policy-making, he said.

Brazil is pushing for a permanent seat on the United Nations Security Council, but enlarging the membership of the Council will not solve anything, he said. Instead, he argued, "its functions and agenda need to be updated to include food security and climate security."

Brazilian diplomacy is facing a growing movement of environmentalists and political opponents who criticise the "postponement" of their environmental and trade policy demands. The reason for their anger is the Brazilian government's "ideological option for the Third World," said Viola.

His view is shared by diplomats and members of the business community who are against Brasilia's policy of seeking stronger ties with Africa, the Middle East and Asia, in an effort to create trade links which they believe are to the detriment of trade with wealthy markets. These alliances have given Brazil a leadership role in the negotiations for a new agreement at the World Trade Organisation.

But when the issue is climate change, these alliances mean that Brazil continues to "save China's bacon," according to José Goldemberg, who was environment minister in 1992 when Brazil hosted the Earth Summit in Rio de Janeiro, where the U.N. Conventions on Climate and Biodiversity were approved.

It is absurd to place China, now an economic and technological powerhouse, in the same category as African countries like Burundi, in terms of need for financial aid and technology transfer to help developing countries mitigate and adapt to climate change, Goldemberg, a physicist and energy expert, said in a televised debate.

The crisis requires cooperation by every country, otherwise the ship will sink anyway, and it won't matter who was historically responsible for the leaks in the hull, he said.

China emitted 5.7 billion tons of carbon dioxide equivalents in 2006, surpassing the 5.6 billion tons emitted by the United States. More alarming is the difference in their annual rates of growth of emissions: eight percent for China and one percent for the U.S., according to statistics from several official and independent sources, said Viola.

Between them, they account for 43 percent of global emissions. China has adopted an economic growth model based on heavy environmental and climate impacts, said Viola, who puts both countries in the "irresponsible" category.

Global climate security depends on a "grand agreement" between the 13 largest emitters, which each contribute over 1.5 percent of the world total, to achieve a substantial reduction in global carbon dioxide emissions, Viola said.

The academic described two alternatives to this future scenario: the Hobbesian, according to which nation-states control their populations, while in the international arena the most powerful nation controls the world order -- which he said would be catastrophic, given current tendencies; and "deepened Kyoto," with more mitigation, but not enough to prevent global temperatures increasing by more than two degrees by 2100.

"A grand agreement will demand the political will for in-depth cooperation for the long term," but the commitment of some leader countries could help to persuade others to come aboard, Viola said. The EU is already committed, and the United States might become a partner after next year's elections.

The "first circle" would be completed with China and India, which is responsible for nearly 11 percent of greenhouse gas emissions. However, it would be difficult for these two countries to curb the strong growth in their emissions, given their dependence on fossil fuels.

In the "second circle" of large emitters, made up of Russia, Brazil, Japan and Indonesia, the main difficulty may stem from Russia, a big exporter of oil and gas, where the élite hope that global warming may grant the country a windfall of more agricultural land.

Japan has one of the lowest levels of carbon intensity among industrialised nations, as it emits only 0.15 tons of carbon dioxide equivalents for every 1,000 dollars of gross domestic product (GDP), compared to 0.40 tons in the United States.

But Japan has not confronted the U.S. about climate change because it depends on U.S. military protection.

Since the break-up of the former Soviet Union, Europe is no longer constrained in the same way.

The equation is a complex one, but an alliance between the U.S., the EU and Japan, with the possible participation of Brazil, might be a very persuasive combination and offer a greater contribution to mitigation of climate change than the rest of the world put together, Viola said optimistically.