Scientists map climate change in a new way
An international consortium of scientists developed a new way to map long term climate change. On 29 November 2012 the group that includes scientists from Utrecht Univeristy, the KNMI, the University of Amsterdam and the Vrije Universiteit publishes their results in the scientific journal Nature.
The new international ‘Palaeosens’- team of physicists and earth scientists, including Henry Hooghiemstra of the UvA institute for Biodiversity and Ecosystem Dynamics (IBED), presents a new, consistent way to measure climate sensitivity in the geological past so that the data can be applied by the Intergovernmental Panel on Climate Change (IPCC).
A new framework to learn from the past
For their study, the scientists collected previously published estimates of climate sensitivity in the last 65 million years. They found a considerable spread in the values of climate sensitivity in the past. However, this could be traced back to different ways in which scientists dealt with feedbacks in the climate system. Therefore, in their article the group presents a framework that enables comparison of estimates of past climate sensitivity. This turned out to be consistent with the climate models used by the IPCC to estimate future climate change.
Using the new method, reconstructions of the climate in the last 65 million years were made. The estimates imply that in the past doubling of the CO2 concentrations led to a warming of 2.2 – 4.8 °C, consistent with current future estimates by the IPCC.
The article is the result of a Academy Colloquium organized with the support of the Royal Dutch Academy of Arts and Sciences (KNAW) in 2011. This colloquium was attended by 40 international experts in the field of past and present climate change.
Palaeosens project members, 'Making sense of palaeoclimate sensitivity', Nature, 491: 683–691. Published 29 November 2012. doi:10.1038/nature11574