"It is extremely likely that human influence has been the dominant cause of observed warming since the mid-20th century," according to the summary issued by the Intergovernmental Panel on Climate Change (IPCC) after a weeklong meeting in Stockholm and meant to guide policymakers in shifting towards greener energies from fossil fuels. "Extremely likely" means a probability of at least 95 per cent, up from 90 per cent in the panel's last report in 2007 and 66 per cent in 2001.

It said the Earth was set for further warming and more heat waves, floods, droughts and rising sea levels as greenhouse gases built up in the atmosphere. The oceans would become more acidic in a threat to some marine life.

The UN's top climate official, Christiana Figueres, said the report underscored a need for urgent action to combat global warming. Governments have promised to agree a UN deal by the end of 2015 to restrict emissions. "To steer humanity out of the high danger zone, governments must step up immediate climate action and craft an agreement in 2015 that helps to scale up and speed up the global response," she said.

A UN panel said on Friday 27-Sep-13, it was more certain than ever that humans were causing global warming and predicted temperatures would rise by 0.3 to 4.8 degrees Celsius (0.5-8.6 degrees Fahrenheit) this century.

The Intergovernmental Panel on Climate Change (IPCC) also projected sea levels would rise by between 26 and 82 centimetres (10.4 and 32.8 inches) by 2100, according to a summary of the first volume in a long-awaited review.

The new document is the first volume in a trilogy that will seek to summarise the status of global warming and its impacts.

The work released in Stockholm comprises a 2,000-page report authored by 257 scientists, plus a 36-page Summary for Policymakers.

The IPCC has delivered four previous assessment reports in its 25-year history.

Source: http://www.climatechange2013.org/

http://www.theguardian.com/environment/video/2013/sep/27/ippc-presents-report-climate-science-video