Ozone, UVR and Climate

The Danish Climate Centre studies upper tropospheric/ lower stratospheric physical processes relevant for changes in the ozone layer and UV radiation level.

We perform systematic surveillance of the ozone layer in accordance with recommendations of the Montreal protocol, which was designed to protect the ozone layer by phasing out the production of substances responsible for the ozone depletion. The DMI is attending to the Danish obligations through the Vienna Convention articles 3.1 and 3.2 that address systematic monitoring of and research into the development of the ozone layer.

The Montreal protocol has proven successful by inducing a turnaround in the trend of increasing levels of ozone depleting substances in the atmosphere, and ozone trends are now studied to see if this propagates to the ozone layer as models predict. By comparing observations with model projections, we seek to assess whether observed changes agree with our current understanding, as represented by model simulations.

Focus areas

Regional Climate Modelling

Global Climate Modelling

Ozone, UVR and Climate

Ice Sheet Modelling

Processes in the Arctic

Developing Countries

Climate Data Host

Ozone layer and UVR monitoring

High quality observations are essential to studies into stratospheric ozone depletion and climate change. The DMI has at its disposal a number of observatories and observation networks that are used to keep a number of atmospheric conditions under surveillance. These observations contribute greatly to the information, research and supervision provided by the DKC and other users.

We produce and disseminate various satellite application facility (SAF) products. This includes the development of operational software and hardware for near real time UV clear sky fields. SAF operations produce ground based UV-index measurements for several measuring sites twice a year including cloud cover corrections. The cloud cover corrected UV-index is presented with the near real time UV products.

Measurements of ozone layer thickness above Denmark and UV radiation levels for Denmark and the rest of the world are presented daily on DMI.dk.

Global UV index, 20 April 2011

International research and collaboration

In close national and international collaboration, the DKC is monitoring and researching into ozone and UV radiation. The monitoring is supported by the Danish Ministry of the Environment, and our measurements contribute to the international Network for the Detection of Atmospheric Composition Change (NDACC).

The Arctic is one of our focus areas, and we are monitoring the restoration of the ozone layer and UV level above Greenland under climate changed atmospheric conditions, from NDACC-stations in Pituffik, Kangerlussuaq and Scoresbysund.

Monitoring data are submitted to databases under NDACC, World Ozone and UV radiation Data Center under the WMO program GAW, WMO’s GCOS and AMAP. The ozone measurements will also contribute to a possible future Danish climate surveillance program.

The SCOUT-O3 project

The five-year project SCOUT-03 was a European Commission Integrated Project that involved 59 partner institutions and over 100 scientists from 19 countries. SCOUT-O3 ran until 31 April 2009 and aimed to develop predictions about the evolution of the coupled chemistry/climate system, with emphasis on ozone change in the lower stratosphere and the associated UV and climate impact.

The central purpose of the SCOUT-O3 project was to provide scientific knowledge for global assessments on ozone depletion and climate change for the Montreal and Kyoto Protocols.

An estimation of how and when the ozone layer and UV radiation will recover, as CFC concentrations decrease, is required within the next few years, and could prove essential to European policy makers, and be used to develop the European position on sustainable development.

Long-term effects of UVR in Europe

In cooperation with several medical and health institutes in Europe, The DKC is involved in the interdisciplinary European project ICEPURE, which aims to determine the beneficial and harmful biological effects of UVR and critical dose levels in relation to personal UVR exposure. This includes studies of vitamin D synthesis, DNA damage and immunosuppression.

The role of the DKC is to combine UV measurements and satellite data and to develop a personalized UVR exposure model in order to model personal UVR exposure of small or large population groups.

Personal exposure data from wristwatch dosimeters worn by volunteers, and from diaries that participants keep of their daily behaviour, will be correlated with location matched ground station and satellite data to develop combinatorial radiative transfer and behavioural models that can be used in climate models to predict future UVR levels and assess the impact of climate change on human UVR exposure.

Measured UVR for a skier(blue)  with  calculated UVR using the SMARTS model with an albedo for total snow cover(red) and a snow cover of approximately 60% (green), 24 March 2010, Wagrain, Austria

Modelling climate impacts

The DKC uses the climate model EC-Earth for studying the stratosphere-troposphere coupling, the climate effects of ozone depletion, and the feasibility of geo-engineering. In the ongoing EU project COMBINE, DKC develops and tests a "high-top" version of EC-Earth with an increased number of stratospheric layers.

It is expected that the new version will increase the realism of the stratospheric impacts on the troposphere and thereby improve the model skills on both intra- seasonal and climatic timescales. The new version will contribute to the CMIP5 ensemble.




Contacts

Head of the Middle Atmosphere Research Division, Niels Larsen, nl@dmi.dk
Phone: (+45) 39157 414

Icepure project, Mette Marie-Louise Grage, mmlg@dmi.dk
Phone: (+45) 39157 451

Edited by Tue Tobias Kosack, ttk@dmi.dk © DMI, 12 May 2011