Ministers have begun talks at the UN climate summit in Cancun, Mexico, amid warnings that time is running out to curb¹ climate change.

墨西哥城市坎昆举行的联合国气候峰会上各国部长开始举行会谈，阻止气候变化迫在眉睫。

Top UN climate official Christiana Figueres said the fate of low-lying islands should be a "wake-up call".

Big differences remain between nations on issues such as cutting emissions³, protection from climate impacts and inspections⁴ of others' emission² curbs⁵.

It is unclear whether those issues can be resolved in the three days left.

Mexican President Felipe Calderon congratulated negotiators for their work so far.

"The work has been difficult, but I see the results of negotiations⁶ are encouraging, although it is clear there are formidable（强大的，可怕的） challenges to overcome," he said in his opening speech.

"What should prevail（盛行） is goodwill⁷, trust and understanding, and with that we will be able to offer the world an opportunity to open a new path when it comes to fighting climate change."

Ms Figueres, the Costa Rican diplomat⁸ who took up the post of UN climate convention (UNFCCC) executive secretary earlier this year, warned that much was at stake（处于险境） .

"The political stakes are high because the effectiveness and credibility of your inter-governmental, multilateral process are in danger," she said.

"And the environmental stakes are high because we are quickly running out of time to safeguard our future.

"Tuvalu, The Maldives, Kiribati, Vanuatu are looking for ways of evacuating⁹ their entire populations because of salt water intrusion（侵入，闯入） and sea-level rise. Their fate is a wake-up call to all of us."

Earlier, the UN Environment Programme (Unep) formally presented delegates with the results of a study published two weeks ago.

It showed that pledges on the table for curbing¹⁰ emissions will not be enough to keep the global average temperature rise below the levels that most governments say they want.

The vast majority of countries want to keep the rise since pre-industrial times to within either 1.5C or 2C.

Lou Leonard from environmental group WWF was one of many campaigners emphasising that the agreement coming out of Cancun must allow for countries to increase their pledges, to close this gap.

"They say they want 2C, the pledges don't get to 2C. It is like the emperor has no clothes," he said.