Human civilization has pushed atmospheric CO2 levels to near 400 parts per million (ppm) for the first time in human existence. The National Oceanic and Atmospheric Administration (NOAA) revised its May 9, 2013 reading at the Mauna Loa observatory in Hawaii, saying it remained fractions of a point below the level of 400 ppm, at 399.89 ppm.
The last time concentrations of Earth's main greenhouse gas reached this mark, during the Pliocene era 5.3 to 2.6 million years ago, the planet was about 3.6 to 5.4 degrees Fahrenheit warmer. The Arctic was 14°F warmer allowing horses and camels to graze in lush savannas that grew at those ancient high latitudes. The Arctic and West Antarctic ice sheets did not exist and sea levels during the mid-Pliocine were about 82 feet higher than today — levels that today would inundate major cities around the world!
Today, with the warming atmosphere, Arctic sea ice is melting much, much faster than even the best climate models had projected. The reason is most likely for faster loss of arctic ice is unmodeled amplifying feed backs in the CO2 cycles, plus recent Paleoclimate research suggests CO2 may have at least twice the effect on global temperatures than currently projected by computer models. “Future warming likely to be on high side of climate projections,” according to a November paper in Science. On our current emissions path, CO2 levels will continue to rise to as much as 650–970 ppm by the year 2100 -- levels last seen when the Earth was and average 29°F hotter and dinosaurs walked the earth. A 29°F rise in temperature would melt all the ice on earth, even in Antarctica, increasing sea levels by 250 feet over just decades.
97% global warming consensus meets resistance from scientific denialism - The robust climate change consensus faces resistance from conspiracy theories, cherry picking, and misrepresentations.A new study led by Clark University and involving the University Colorado Boulder found that all glacial regions lost mass from 2003 to 2009, with the biggest ice losses occurring in Arctic Canada, Alaska, coastal Greenland, the southern Andes and the Himalayas. The glaciers outside of the Greenland and Antarctic sheets lost an average of roughly 260 billion metric tons of ice annually during the study period. "Because the global glacier ice mass is relatively small in comparison with the huge ice sheets covering Greenland and Antarctica, people tend to not worry about it," said CU-Boulder Professor Tad Pfeffer, a study co-author. But Greenland's inland ice sheet is now beginning to melt, too. Greenland's ice sheet saw melting across nearly all of its surface last summer due to higher than normal temperatures.
Media Still Overlooks 90% Of Global Warming, Washington Post Still Won’t Fact Check Columnists.
Most climate scientists don't think that the Antarctica and Greenland icecaps will thaw yet this century. Many studies since 2007, including by the World Bank, the U.S. National Oceanic and Atmospheric Administration (NOAA) and a report for the Arctic Council, put the upper limit of sea surface rise at about six feet by the year 2100. However, when 97 percent of Greenland’s ice experienced at least some melting in July 2012, scientists began wondering if it was a one-time phenomenon. Now a new study in Geophysical Research Letters indicates it is a sign of things to come and by 2025, there is a 50-50 chance of it happening annually. Some climate scientists have started to wonder whether Widespread Greenland Melting Is To Become The Norm In Next Two Decades. Miami, As We Know It Today, Is Doomed by Sea Rise; It’s Not A Question Of If. It’s A Question Of When.
Imagine sea levels rising 82 feet higher, and more, than today... Eminent climatologists think a "Great Flood" is inevitable if current CO2 emission rates continue.
Based on research by NASA astro-biologist and paleontologist Professor Peter Ward and a group of respected American climatologists, the Earth Under Water video is an eye-opening documentary.
This BBC documentary uses scientific evidence past and present, archive footage, location photography and CGI to explore the terrifying consequences should the atmosphere's CO2 levels treble over the next 100 to 300 years, as predicted.
Step by step, the BBC documentary paints a chilling picture of the world as the sea levels rise, unraveling the science behind this cataclysm, revealing when it could strike and what its impact would be on humanity. The film also questions experts and politicians about what measures can be taken now to stop the current rise of CO2 emissions, and explores how extreme engineering will buy us time. But the message of this film is stark, spelling out in graphic detail the Earth's apocalyptic future that we have been avoiding.
