Anthropogenic climate change promotes increased release of CO2 from the terrestrial biosphere and the oceans – this, in turn, increases global warming. For each degree Celsius of global warming, CO2 levels in the atmosphere increased by roughly 3%. This conclusion represents the outcome of a study conducted by researchers of the NCCR Climate. Their paper was just published in the journal "Nature". As a result of these investigations, they are now in the position to estimate with considerably greater accuracy to what extent the atmospheric CO2 concentrations were influenced by climate change in the preindustrial past. Global temperatures are currently more than 0.3 degrees Celsius higher than the warmest period of the last 1,000 years. This suggests that human activities have widened the range of natural temperature fluctuation in this millennium by 75%. The strength of feedback between carbon cycle and warming is still being extensively debated within the scientific community. The NCCR Climate researchers now managed to produce a reliable mean value for the extent of feedback between temperature and CO2. "By serving as a benchmark for the past, these new data may help the climate modelling community make more accurate predictions for the future," stated David Frank, the lead author of the paper.
