WORLD METEOROLOGICAL ORGANIZATION

UNITED NATIONS ENVIRONMENT PROGRAMME

DENMARK

The DMI is engaged in the following research and monitoring projects, relevant to stratospheric ozone depletion:

-"European Stratospheric Monitoring Stations in the arctic: A European contribution to the Network for the Detection of Stratospheric Change (NDSC)". At Thule (77 °N, 69 °W) the DMI performs balloon-borne backscatter observations of aerosols and polar stratospheric clouds (PSCs). Modelling of the formation of PSCs is also made. The DMI hosts the arctic NDSC site at Thule.

-"Stratospheric climatology using UV/Visible spectroscopy". The DMI carries out UV/Visible measurements of O₃, NO₂, and possibly OCIO and BrO at Thule.

-"Ozone soundings as a tool for detecting ozone change". The DMI carries out ozone soundings from Thule and Scoresbysund (70 °N, 22 °W) .

-"Ultraviolet radiation in the arctic: past, present and future". The DMI measures UV radiation at Thule with a spectroradiometer.

-"Ozone as a climate gas". The DMI performs ozone soundings from Scoresbysund, investigates trends and carries out GCM-modelling with the purpose of detecting climate changes.

-"Gravity waves in the stratosphere". The DMI makes observations of 3-D winds with a radar at Sondre Stromfjord (67 °N, 51 °W) with the purpose of investigating gravity waves which may produce polar stratospheric clouds. The PSCs are observed by lidar and backscatter sondes. The experimental observations are compared with modelling of the waves.

-Observations of O₃ and UV-B radiation are made with Brewer spectrometers at Copenhagen (56 °N, 12 °E) and Søndre Strømfjord.

-Based on meteorological analysis from ECMWF, the DMI performs trajectory model calculations of transport of ozone and other trace gases.

University of Copenhagen

-"Investigation of increased UV-B radiation on arctic heathland (Greenland)" is carried out by The Botanical Institute, Department of Ecology. The Department is engaged in identification and characterisation of particular sensitive plant components of terrestrial arctic ecosystems, mainly Cassiope tetragona heath with the lichen Cladonia mitis. Field experiments are carried out at Oaanaaq (77 °N, 69 °W) and green-house experiments in Copenhagen.

-"Laboratory studies and modelling of heterogeneous chemistry in the stratosphere" are made by the Institute of Chemistry, Chemical Laboratory V. Results from this combined laboratory and modelling study will provide detailed information on the impact of heterogeneous chemical reactions on the stratospheric ozone depletion. The study addresses reactions relevant to both the middle and high latitudes. The objective is to obtain new information on the heterogeneous chemical processes taking place on the stratospheric sulphuric acid aerosol and which influence the partitioning of hydrogen, halogen and nitrogen species in the lower stratosphere over middle to high latitudes.