The Guardian reports: The Earth is locked on an “irreversible” course of climatic disruption from the buildup of greenhouse gases in the atmosphere, and the impacts will only worsen unless nations agree to dramatic cuts in pollution, an international panel of climate scientists warned Sunday.

The planet faces a future of extreme weather, rising sea levels and melting polar ice from soaring levels of carbon dioxide and other gases, the U.N. panel said. Only an unprecedented global effort to slash emissions within a relatively short time period will prevent temperatures from crossing a threshold that scientists say could trigger far more dangerous disruptions, the panel warned.

“Continued emission of greenhouse gases will cause further warming and long-lasting changes in all components of the climate system, increasing the likelihood of severe, pervasive and irreversible impacts,” concluded the report by the United Nations’ Intergovernmental Panel on Climate Change (IPCC), which draws on contributions from thousands of scientists from around the world.

The report said some impacts of climate change will “continue for centuries,” even if all emissions from fossil-fuel burning were to stop. The question facing governments is whether they can act to slow warming to a pace at which humans and natural ecosystems can adapt, or risk “abrupt and irreversible changes” as the atmosphere and oceans absorb ever-greater amounts of thermal energy within a blanket of heat-trapping gases, according to scientists who contributed to the report.

“The window of opportunity for acting in a cost-effective way — or in an effective way — is closing fast,” said Michael Oppenheimer, a Princeton University geosciences professor and contributing author to the report. [Continue reading…]

See the 40-page summary of the Climate Change 2014 Synthesis Report and the 116-page complete report.