Ice drilling station
We know quite a lot about the climate in the past, but have you ever wondered how we know what we know?
Much of what we know today about the climate far back in time, we have learned by studying "drill cores", a kind of historical climate archive, which can be obtained by drilling deep into the ice in, for example, Greenland or Antarctica.
At the ice drill station, you get to try for yourself what it can be like to pick up an ice drill core and make measurements of the ice content. Then we can see how temperature and carbon dioxide levels have developed, and how the climate has varied between ice ages and warm periods over the past 150,000 years.
At the ice core drilling station, you will learn how to study climate change through history. You will have the chance to pull up a core sample from the glaciers in Greenland and carry out measurements to read the temperature and carbon dioxide levels for the past 150 000 years.
The station is based on current research on climate change and includes a film in which researcher Jesper Sjolte from the Department of Geology in Lund talks about the studies on the ice in Greenland. The data that is used for climate reconstructions comes from measurements from Greenland and Antarctica, where the ice cap is over 3000 metres thick and can be used to look at climate change as far back as 400 000 years ago.
To uncover historical climate data, researchers look at air bubbles preserved in the ice that contain ’old air’ – by measuring the levels of carbon dioxide in these bubbles it is possible to compare historical levels with current carbon dioxide levels in the atmosphere (we currently have approximately 400 ppm CO2). The temperature can be recreated by looking at the relationship between different oxygen isotopes (that is, different kinds of oxygen atoms). Ice and water normally have different distributions of the different oxygen isotopes, so it is possible to see that the balance has varied if there has been a lot of ice (cold climate) or lots of water (warm climate).
To recreate even older climate development (millions of years ago) it is not possible to use ice. Instead, researchers look at changes in sedimentary rock and fossils from plants and animals.
The North Greenland Eemian Ice Drilling - NEEM - is an international ice core research project aimed at retrieving an ice core from North-West Greenland (camp position 77.45°N 51.06°W) reaching back through the previous interglacial, the Eemian. The project logistics is managed by the Centre for Ice and Climate, Denmark, and the air support is carried out by US ski equipped Hercules managed through the US Office of Polar Programs, National Science Foundation.
Links
Photo, top: NEEM ice core drilling project, www.neem.ku.dk. Photographer: Henning Thing.