vrijdag 11 december 2009

Modelling activities; chemistry-climate model and obserations


The last report was already the 9th of September where I then indicated that not much had happened since my return from Greenland in July. However, we have now Brian Seok from the Institute of Arctic and Alpine Research (INSTAAR) at Colorado University, Boulder, visiting me to work together on the use of a column model version of a chemistry-climate model to help interpret all observations at Summit. For Brian, who has a more experimental background, this is a great opportunity to get introduced in the "challenges" of modelling the complex behaviour of chemical compounds in the harsch environment over- and within the Greenland icesheet. Before we can start focussing more on a comparison of the observed and simulated exchange of reactive compounds such as ozone and nitrogen (di)oxides we first need to know that the model is doing a reasonable job on simulating the local meteorology at the site. This is because the chemical processes all strongly depend on many meteorological parameters such as temperature, wind speed and radiation. In the figure you can find one result of the very nice comparison that Brian has been doing last 2 months; it shows a comparison of the measured and simulated net radiation at the surface showing that the model is reasonably well simulating this important parameter that controls the snowpack temperature but also the so-called "photolysis" of chemical compounds like ozone and nitrogen dioxide.

In the near future we will show more results and hope that Brian will soon be able to write a nice publication about these very interesting findings,

Laurens