UN: climate change will have 'abrupt and irreversible' consequences

A peek at the IPCC report from the Times (UK): A panel of the United Nations' leading scientists is to warn that climate change could have "abrupt and irreversible" consequences, in a landmark document designed to force action from member states on the issue. The Intergovernmental Panel on Climate Change (IPCC) report is seen as one of the most influential documents produced on the global warming issue to date, with the goal of forcing some of the world's biggest polluters to curb their emissions.

The Times has learnt that IPCC delegates – made up of some of the world's most eminent scientists – agreed on a text this morning after all-night negotiations in Spain, in which it was decided that tough wording would be needed. As a result, the text of the draft report, which is due to be officially released tomorrow by Ban Ki Moon, the UN Secretary-General, will caution that human activity could lead to "abrupt and irreversible" changes in our climate unless action is taken.

The report will summarise the main points from three huge documents issued this year covering the evidence for climate change; the present and possible future impacts of it; and the options for tackling the peril. After the release of their report, scientists hope that UN member states will come up with a "roadmap" to cut carbon emissions at a summit in Bali next month.

Measures to be discussed in the December 3-14 conference are aimed at cutting greenhouse gas pollution after 2012, when current pledges under the UN’s Kyoto Protocol expire. In three previous reports, IPCC experts have agreed that the rise in Earth’s temperature observed in the past few decades is principally the result of human activity, not natural causes, as sceptics have argued. The reports stated that the impacts of climate change are already visible, in the form of retreating glaciers and snow loss in alpine regions, thinning Arctic summer sea ice and thawing permafrost.

They add that, by the year 2100, global average surface temperatures could rise by between 1.1 C (1.98 F) and 6.4 C (11.52 F) compared with 1980-99 levels, while sea levels will rise by between 18 and 59 centimetres (7.2 and 23.2 inches), according to the IPCC’s forecast. Heatwaves, rainstorms, drought, tropical cyclones and surges in sea level are among the events expected to become more frequent, more widespread and more intense this century. As a result, water shortages, hunger, flooding and damage to homes will be a heightened threat.