Scientists have long presented evidence that the current period of global warming is unpredicted - an anomaly - and that human activity since the industrial revolution spurred unprecedented climate change. Of course some argue that the climate change we're seeing in this Holocene period isn't anthropogenically generated, we're either in a natural cycle climatic cycle or the warming started thousands of years ago with deforestation by early human activity. As the two sides present their evidence, environmental policy evolves after the scientific research is established when hopefully the chinks are uncovered.
Research on climate and atmospheric gases during several glacial periods helps predict future climate patterns and discern via historical data whether earth's current climate is cyclical or unique. The European Project for Ice Coring in Antartica (EPICA) collects data and analysis from international teams of scientists who embark on bone-chilling expeditions to gather historical information about the atmosphere from deep ice cores they drill in Antarctica. Analysis of air bubbles trapped in the ancient ice pack gives information about greenhouse gases and climate changes hundreds of thousands of years ago. The previous core at the Vostok, Antarctica site provided data through 440,000 years ago. The recent drill provides atmospheric and climate data from 650,000 years ago.
The Antarctic information can be compared to similiar investigations in Greenland to determine what triggers climate changes in the two hemispheres. The scientists also study the historical pace of climate change and the transitions between glacial to interglacial periods.
This week's Science published studies by two research groups. Taken together, the results show that carbon dioxide levels in the atmosphere vary with climate in Antarctica. Temperature changes are periodic, however the periods were historically stable. The most recent periods were 10,000 years, a relatively short temperature change. The previous period (before 400,000 years ago) lasted for 30,000 and looked more like the current Holocene period.
Edward J. Brook, the author of the perspective, ("Tiny Bubbles For All"), in Science writes that the current levels of "carbon dioxide and methane levels just before the Industrial revolution" are higher then in the previous 650,000 years. Since CO2 levels are higher now then it ever, scientists predict that temperatures will continue to rise. The evidence bolsters previous research and concurs with predictions made in response to the "EPICA Challenge", which asked scientists to predict the results of the ice core analysis before the data was presented. The scientists were successful at predicting the data outcomes prior to the completion of the studies, which is important because we need to build public confidence in scientists' ability to predict future patterns based on evidence at hand.
At Real Climate climatologists and their readers discuss the research in depth. A previous Acronym Required article discussed some of the challenging aspects of Science Communication.
