Humans are in danger of making large parts of the Earth uninhabitable for thousands of years because of man made climate change, according to new evidence based on geological records. The US study predicted that if society continues burning fossil fuels at the current rate, atmospheric levels of carbon dioxide could rise from the current level of 390 parts per million (ppm) to 1,000 by the end of this century. The last time the world had such high levels of carbon dioxide temperatures were on average 29F(16C) above pre-industrial levels. Evidence has been found of crocodiles and palm trees at the Poles and only small mammals were able to survive.
Jeffrey Kiehl, of the National Center for Atmospheric Research (NCAR), who carried out the study, said the Earth could return to such temperatures over hundreds or even thousands of years. But unlike last time, when it happened over millions of years, temperatures will rise too fast for species to adapt and change. In the short term he said temperatures could rise by more than 10.8F (6C) by the end of the century, which will also wipe out species. "This is happening at such a rate how will species, including humans, respond? The implications for the biosphere is of great concern." Dr Kiehl not only looked at geological records but also computer models to predict what will happen if carbon dioxide levels rise at such a rate. He included 'feed back factors', such as melting sea ice, methane released from thawing permafrost and Amazon die-back.
This showed that temperatures will increase much faster than previously thought as a result of rising carbon dioxide. "If we don't start seriously working toward a reduction of carbon emissions, we are putting our planet on a trajectory that the human species has never experienced," he said. "We will have committed human civilization to living in a different world for multiple generations." Dr Kiehl hit back at critics who claim that acting on climate change by reducing the use of fossil fuels will upset the world order. "A truly conservative position is to conserve what we have, to not radically change things and if we do not want to radically change the environment then the conservative approach is to conserve the Earth as the human species has known it ever since we have been around on this planet."
