There's even less time for humanity to try to curb global warming than recently thought, according to a new in-depth scientific assessment by 26 scientists from eight countries.
Sea level rise, ocean acidification and the rapid melting of massive ice sheets are among the significantly increased effects of human-induced global warming assessed in the survey, which also examines the emissions of heat-trapping gases that are causing the climate change.
"Many indicators are currently tracking near or above the worst-case projections" made three years ago by the world's scientists, the new Copenhagen Diagnosis said.
The scientists also calculate that the world's emissions of heat-trapping gases must peak in less than 10 years and then dive quickly to nearly zero, if warming of more than another 2 degrees Fahrenheit above the current annual global temperature is to be prevented after 2050.
Any warming of more than 2 degrees F above current temperatures has been generally agreed among governments around the world to be "dangerous," though what "dangerous" means is still debated.
This is the first comprehensive update of leading peer-reviewed climate science in the three years since the last report of the intentionally thorough and slow-paced Intergovernmental Panel on Climate Change was finalized.
That report is now widely recognized to be out of date in important ways.
This is because over the past three years, hundreds of new scientific field accounts of global warming's impacts, as well as improved peer-reviewed analyses of global warming itself in both the deep past and the very near future, have depicted earth's atmosphere as far more "sensitive" to the invisible CO2, methane and other human-sourced greenhouse gases than had been hoped.
"Mother nature puts a limit on how long you can dither and procrastinate," climatologist Richard Somerville, one of the study's authors, told ABC News.
"We found that several vulnerable elements in Earth's climate system -- like the Amazon and other big rain forests, like the great ice sheets that have so much sea level locked up in their ice -- could be pushed toward abrupt or irreversible change if we go on toward 2100 with our business-as-usual increase in emissions of greenhouse gases," he said.
Because the next IPCC report is not due before 2013, there had been a growing concern among many of the world's climate scientists that an update of the latest solid data would be needed, he said, if negotiations by the 192 nations gathering at the Copenhagen climate summit, scheduled for Dec. 7-18, were to be based on reality.
By phone from his base at Scripps Institution of Oceanography in California, Somerville told ABC News that the 26 authors of the survey all donated their time and expertise.
"The money we needed for basic transportation to get us to and from our big global review session in Copenhagen in March and for basic communication expenses turned up from the Live Earth philanthropy," Somerville said.
Live Earth, founded by producer Kevin Wall, in partnership with former Vice President Al Gore, is a for-profit company that uses concerts, media and other events to encourage awareness worldwide about environmental issues.