Where has the heat gone? AUC lecturer interviewed on global warming

30 September 2013

The Dutch newspaper “Trouw” recently interviewed Bart Verheggen, teacher of the AUC courses “System Earth”, “Biogeochemical Cycles” and “Energy, Climate and Sustainability” on the short-term changes in the trend in global warming. The average surface temperature has scarcely increased after the exceptional warmth of 1998. Data suggest that the surplus of energy, as a result of the enhanced greenhouse effect, has largely been absorbed by the oceans. The earth has continued to receive more energy from the sun than it has radiated to outer space. These short-term variations to how heat is distributed between atmosphere and ocean do not materially affect climatologists’ view of a warming planet: The seas are still rising, ice is still melting and the planet is still gaining heat. Bart Verheggen underscored the importance of looking at long-term trends rather than short-term variation when making judgments about climate change. However, the smaller upward trend in recent surface temperatures was unexpected, which led to climate sceptics questioning the climate models. According to Bart Verheggen, the change in trend has a minor impact on the estimation of the sensitivity of the climate to rising greenhouse gas concentrations. “Climate sensitivity should also be consistent with the climate changes that occurred in the deep past. These indicate that the climate is indeed sensitive to changes to the energy balance.” The UN Intergovernmental Panel on Climate Change (IPCC) will publish the first installment of its fifth climate report this coming Friday. The full article (in Dutch) is provided below. Bart Verheggen was also quoted by BBC news, see link.