Boost for Copenhagen as Obama sets target for emissions cut

US President announces he will attend next month's key climate change summit

Prospects for a global climate deal at the UN Conference in Copenhagen next month strengthened yesterday when the United States put a number on the table and announced a target for cutting US greenhouse gas emissions.

The White House statement, that President Barack Obama was prepared to offer a US emissions reduction target "in the range of 17 per cent below 2005 levels by 2020", means a multilateral treaty to fight global warming is now a possibility.

The US – the world's biggest carbon emitter until it was overtaken by China – was the last developed country without a formal climate target, and it had become clear in recent weeks that without a "US number" for the negotiations, the developing countries, led by China and India, would refuse to pledge specific action of their own to cut back on their soaring CO2 emissions – and thus the conference would fail.

The ball is now back in the developing countries' court, with attention shifting to China, which may make a statement about its climate ambitions later in the week. The White House announcement specified that the US target would be pledged "in the context of an overall deal in Copenhagen that includes robust mitigation contributions [to reduce greenhouse gases] from China and the other emerging economies."

The White House further raised hopes for a successful climate deal by announcing that Mr Obama would attend the summit in person. However, there was disappointment, and some puzzlement, that his visit will be in the first week, on 9 December – the day before he collects his Nobel Peace Prize in Oslo – and not on the final two days of the summit on December 17 and 18, when most world leaders are expected to be present, and the crucial talks to seal the deal will take place.

The announcement of the US target, however, matters more than the date of the president's visit. It is qualified in various ways and will be widely regarded as far from satisfactory in its detail, but the important point is that it has been publicly set – something which represented a considerable political risk for Mr Obama.

His administration has been hamstrung in its climate policy by the necessity of securing congressional agreement for any pledges. The White House is only too conscious that the Senate declined to ratify the current international treaty, the 1997 Kyoto protocol, although the US had officially signed it, and so it has been waiting for climate legislation, which includes emissions-target proposals, to pass through Congress.

A climate bill has passed through the House of Representatives, but the equivalent bill in the Senate has become bogged down because of the passage of the President's healthcare reforms, and has no chance of passing before the Copenhagen conference ends.

For Mr Obama to announce a target in advance, therefore, risked a clash with the Senate, and the possibility that it might ultimately refuse to sanction his proposals. That he has done so undoubtedly means that congressional assurances have been received that this will not be the case. The White House statement is careful to specify that the target will be "ultimately in line with final US energy and climate legislation."

The US target itself, which is the same as the target contained in the House of Representatives bill proposed by Congressmen Henry Waxman and Edward Markey, promises less than it may seem, as it proposes its cut "in the range of 17 per cent" from a baseline year of 2005, whereas the EU and most developed countries are using a much tougher baseline year of 1990. The 17 per cent on 2005 equates to about a 3 per cent cut when compared to 1990 levels.

For comparison, the EU has promised to cut C02 to 20 per cent below 1990 levels by 2020, which will climb to 30 per cent if there is a successful deal next month. Britain's own pledge is to cut emissions by 34 per cent by 2020. Japan has pledged a 25 per cent cut by the same date and Norway, a cut of 40 per cent.

But the fact that America has an official climate target at all, for the first time since President George W Bush withdrew the US from Kyoto in March 2001, is an enormous step forward in the search to construct a new global-warming treaty. It is not a sufficient condition for success – but it is a necessary one.

17%

The size of the proposed US cut in CO2 emissions.