DENMARK
1.OBSERVATIONAL ACTIVITIES
The Danish Meteorological Institute (DMI),in collaboration with the Danish Environmental Protection Agency, has conducted continuous measurements of the stratospheric ozone layer. Daily ground-based measurements of the ozone layer thickness as well as weekly balloon based measurements of the vertical ozone profiles have been performed in Denmark and Greenland. The measurements have been reported to international databases. In addition, the measurements are incorporated in validation of satellite measurements. Balloon-based measurements of the ozone layer have often been conducted as part of larger international projects such as Match-campaigns.
1.1Column measurements of ozone and other gases/variables relevant to ozone loss.
Daily observations of total ozone have been performed by the DMIin Denmark and Greenland:
Station / Location / Instrument / Start of observationsCopenhagen / 56N, 12E / Brewer Mark IV
Brewer Mark III / May 1992
January 2014
Sondre Stromfjord
(Kangerlussuaq) / 67N, 51W / Brewer Mark II
Brewer Mark III / September 1990
February 2010
Thule Air Base
(Pituffik) / 77, 69W / SAOZ
1024 diode array / September 1990
1.2 Profile measurements of ozone and other gases/variables relevant to ozone loss
Weekly ozone soundings have been performed using balloon-borne EEC sensors from Scoresbysund (Illoqqortoormiut, 71N, 22W) since January 1993. Ozone soundings have also been performed oncampaign basis from Thule Air Base each winter since January 1992 and occasionally from Copenhagen.
1.3UV measurements
1.3.1Broadband measurements
A Yankee Environmental Systems model UVB-1 radiometer has been operated by DMI in Copenhagen since 1996. A custom UV radiometer (erythemally weighted UV and total UV-A) has been in operation in Thule (Pituffik) since 1993 and owned by Public Health England (former Health Protection Agency and National Radiological Protection Board), the UV-B part of the instrument being very similar to the Solar Light model 500 UV-B radiometer.
1.3.2Narrowband filter instruments
A narrowband filter instrument – Biospherical Inc., model GUV2511 – has been operated on the east coast of Greenland at Scoresbysund (Illoqqortoormiut) by DMIin the period 2008-2015.
1.3.3Spectroradiometers
At Sondre Stromfjord (Kangerlussuaq) the Brewer MkII instrument has measured spectral UV-B (290-325nm) since late 1990 and the Brewer MkIII instrument since February 2010.
2. RESULTS FROM OBSERVATIONS AND ANALYSIS
Summer (June, July, August) average column ozone measurements, based on NASA TOMS Nimbus 7 version 8 (years 1979-1991) and DMI Brewer (years 1992-2016) from Sondre Stromfjord (Kangerlussuaq), Greenland, are shown in left-hand side in the figure below.
Likewise summer (June, July, August) average column ozone measurements, based on NASA TOMS Nimbus 7 version 8 (years 1979-1991) and DMI Brewer (years 1992-2016) from Copenhagen, Denmark, are shown in the right-hand side of the figure. Neither data set shows significant trends since 1994.
Below is shown the 23-year long record of weekly ozone soundings from Scoresbysund (Illoqqortoormiut). Shown are the vertical profiles of ozone partial pressure (mPa).
3. THEORY, MODELLING, AND OTHER RESEARCH
DMI has participated in major European Arctic and tropic campaigns since the beginning of the 1990's including EASOE, SESAME, THESEO, THESEO-2000-SOLVE, VINTERSOL, HIBISCUS, and Scout-AMMA, as well as a long series of EU-projects. The research was based on a broad spectrum of accessible observations and analyses of meteorological conditions in the stratosphere.
DMI participates in the EC-Earth climate model development, in particular regarding an improved representation of the stratosphere, and studies are performed on the downward influence from the stratosphere on tropospheric climate.
Using the personal exposure data combined with satellite and ground station data DMI has participated in the development of more accurate models to assess the impact of climate change on future UVR exposure to European populations.
Analysis of tropospheric ozone from selected Arctic stationshas been conducted using funding from Nordic Council of Ministers. The work was done with Nordic partners from NILU and FMI. The model used contained a trend, an annual cycle and noise. Parameters were determined using a Metropolis-Hastings algorithm. A sample result is shown below for Scoresbysund at 500 hPa. Cyan curve is annual cycle and green curve is trend.
4.DISSEMINATION OF RESULTS
4.1Data reporting
The measurements are reported to databases under Network for the Detection of Atmospheric Composition Change (NDACC) and World Ozone and UV-radiation Data Center (WOUDC) under the WMO-programme Global Atmosphere Watch (GAW), as well as to NILU. Brewer data has since 2016 been uploaded to the EUBrewnet database, a result from COST Action ES1207.
4.2Information to the public
UV-index forecasts, based on Danish total ozone measurements, were initiated at DMI in summer 1992. This public service runs permanently, made public on the Internet and in several media. DMI is responsible for the Near Real Time UV-index processing as part of the EUMETSAT Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring and provides daily global maps of clear sky UV-indices. DMI has initiated a UV service for Greenland in collaboration with the Greenland Department for Health in 2008. DMI’s ozone measurements are made available on the Internet ( together with a yearly updated status report (in Danish language).
4.3Relevant scientific papers
G. Ancellet, E. Orlandi, E. Real, K.S. Law, H. Schlager, F. Fierli, J.K. Nielsen, V. Thouret, and C. Mari: Tropospheric ozone production related to West African city emissions during the 2006 wet seaso, AMMA campaign. Atmos. Chem. Phys., 11, 6349-6366, 2011.
K. Baczynska, John B. O'Hagan, Andy J. Pearson, P. Eriksen:Temperature correction of UV spectral solar measurements for ICEPURE project. Photochemistry and Photobiology, 87; 1464-1467, 2011.
C. Di Biagio, A. di Sarra, P. Eriksen, S.E. Ascanius, G. Muscari and B. Holben: Effect of surface albedo, water vapour, and atmospheric aerosols on the cloud-free shortwave radiative budget in the Arctic. Climate Dynamics. DOI 10.1007/s00382-011-1280-1. 2012
A. J. Charlton-Perez, M. P. Baldwin, T. Birner, R. X. Black, A. H. Butler, N. Calvo, N. A. Davis, E. P. Gerber, N. Gillett, S. Hardiman, J. Kim, K. Krueger, Y.-Y. Lee, E. Manzini, B. A. McDaniel, L. M. Polvani, T. Reichler, T. A. Shaw, M. Sigmond, S.-W. Son, M. Toohey, L. J. Wilcox, S. Yoden, B. Christiansen, F. Lott, D. Shindell, S. Yukimoto, and S. Watanabe,On the lack of stratospheric dynamical variability in low-top versions of the CMIP5 models, J. Geophys. Res., 118, 2494-2505, 2013.
B. Christiansen, Stratospheric bimodality: Can the equatorial QBO explain the regime behavior of the NH winter vortex?, J. Climate, 23(14), 3953-3966, 2010.
B. Christiansen, Straight line fitting and predictions: On a marginal likelihood approach to linear regression and errors-in-variables models, J. Climate, 27(5), 2014-2031, 2014.
F. Hendrick, J.-P. Pommereau, F. Goutail, R.D. Evans, D. Ionov, A. Pazmino, E. Kyrö, G. Held, P. Eriksen, V. Dorokhov, M. Gil, and M. Van Roozendael: NDACC/SAOZ UV-visible total ozone measurements: improved retrieval and comparison with correlative ground-based and satellite observations. Atmos. Chem. Phys., 11, 5975-5995, 2011.
G. L. Manney, M. Santee, M. Rex, N.J. Livesey, M. C. Pitts, P. Veefkind, E. R. Nash, I. Wohltmann, R. Lehmann, L. Froidevaux, L. R. Poole, M. R. Schoeberl, D. P. Haffner, J. Davies, V. Dorokhov, H. Gernandt, B. Johnson, R. Kivi, E. Kyrö, N. Larsen, P. F. Levelt, A. Makshtas, C. T. McElroy, H. Nakajima, M. C. Parrondo, D. W. Tarasick, P. v. d. Gathen, K. A. Walker and N. S. Zinoviev,, Unprecedented Arctic ozone loss in 2011, Nature 478, 469–475, 2011, doi:10.1038/nature10556
C. H. Mari, Reeves, C. E., Law, K. S., Ancellet, G., Andrés-Hernández, M. D., Barret, B., Bechara, J., Borbon, A., Bouarar, I., Cairo, F., Commane, R., Delon, C., Evans, M. J., Fierli, F., Floquet, C., Galy-Lacaux, C., Heard, D. E., Homan, C. D., Ingham, T., Larsen, N., Lewis, A. C., Liousse, C., Murphy, J. G., Orlandi, E., Oram, D. E., Saunois, M., Serça, D., Stewart, D. J., Stone, D., Thouret, V., Velthoven, P. v. and Williams, J. E. , Atmospheric composition of West Africa: highlights from the AMMA international program. Atmospheric Science Letters, n/a. doi:10.1002/asl.289, 2010.
J. K. Nielsen, M. Foster, and A. Heidinger: Tropical stratospheric cloud climatology from the PATMOS-x dataset: An assessment of convective contributions to stratospheric water. Geophys. Res. Lett., 38, L18801, doi:10.1029/2011GL049429, 2011.
J.- P. Pommereau, Garnier,A., Held,G., Gomes,A.M., Goutail,F., Durry,G., Borchi,F., Hauchecorne,A., Montoux,N., Cocquerez,P., Letrenne,G., Vial,F., Hertzog,A., Legras,B., Pisso,I., Pyle,J.A., Harris,N.R.P., Jones,R.L., Robinson,A.D., Hansford,G., Eden,L., Gardiner,T., Swann,N., Knudsen,B., Larsen,N., Nielsen,J.K., Christensen,T., Cairo,F., Fierli,F., Pirre,M., Marécal,V., Huret,N., Rivière,E.D., Coe,H., Grosvenor,D., Edvarsen,K., DiDonfrancesco,G., Ricaud,P., Berthelier,J.-J., Godefroy,M., Seran,E., Longo,K., and Freitas,S.: An overview of the HIBISCUS campaign, Atmos. Chem. Phys., 11, 2309-2339, doi:10.5194/acp-11-2309-2011, 2011.
J.-P. Pommereau, F. Goutail, F. Lefevre, A. Pazmino, C. Adams, V. Dorokhov, P. Eriksen, X. Zhao (2013): Why unprecedented ozone loss in the Arctic in 2011? Is it related to climate change? Atmos. Chem. Phys., 13, 5299–5308. doi:10.5194/acp-13-5299-2013.
J.-P. Vernier, J.-P. Pommereau, L.W. Thomason, J. Pelon, A. Garnier, T. Deshler, J. Jumelet, and J.K. Nielsen: Overshooting of clean tropospheric air in the tropical lower stratosphere as seen by the CALIPSO lidar. ACP, Vol.11, pp. 9683-9696 SRef-ID: 1680-7324/acp/2011-11-9683, 2011.
M. Bodekær, G. I. Harrison, P. Philipsen, B. Petersen, M. Triguero-Mas, A. W. Schmalwieser, M. Rogowski-Tylman, P. Dadvand, A. Lesiak, J. Narbutt, P. Eriksen, J. Heydenreich, M. Nieuwenhuijsen, E. Thieden, A. R. Young, HC. Wulf. Personal UVR exposure of farming families in four European countries. J. Photochem. Photobiol. B, Biology 10/2015; 153:267-275. DOI:10.1016/j.jphotobiol.2015.10.002.
Christos S. Zerefos, Kostas Eleftheratos, John Kapsomenakis, Stavros Solomos, Antje Inness, Dimitris Balis, Alberto Redondas, Henk Eskes, Marc Allaart, Vassilis Amiridis, Arne Dahlback, Veerle De Bock, Henri Diémoz, Ronny Engelmann, Paul Eriksen, Vitali Fioletov, Julian Gröbner, Anu Heikkilä, Irina Petropavlovskikh, Janusz Jarosławski, Weine Josefsson, Tomi Karppinen, Ulf Köhler, Charoula Meleti, Christos Repapis, John Rimmer, Vladimir Savinykh, Vadim Shirotov, Anna Maria Siani, Andrew R. D. Smedley, Martin Stanek, René Stübi. Detecting volcanic sulfur dioxide plumes in the Northern Hemisphere using the Brewer spectrophotometer, other networks, and satellite observations. Atmos. Chem. Phys., 17, 551-574, 2017.doi:10.5194/acp-17-551-2017.
Christiansen, B., Jepsen, N., Kiwi, R., Hansen, G.H., Larsen, N. and Korsholm, U. (2015): Time Series Analysis of Arctic tropospheric ozone as a short-lived climate forcer. Nordic Council of Ministers.
5.PROJECTS AND COLLABORATION
Thule (Pituffik), Sondre Stromfjord (Kangerlussuaq), and Scoresbysund (Ittoqqortoormiit) are Arctic stationswithin the Network for the Detection of Atmospheric Composition Change. In addition to the DMI instrumentation, aerosol lidars are operated at these stations by the University of Rome (Italy) and SRI International (USA), respectively, together with an FTIR spectrometer at Thule, operated by NationalCenter for Atmospheric Research (USA). DMI also collaborates with Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS) (France) for daily total ozone measurements by a SAOZ instrument at Scoresbysund.DMI participates from Thule and Scoresbysund in the yearly Match-campaigns, coordinated by the Alfred Wegener Institute in Germany, with ozone soundings in the Arctic to quantify the chemical ozone depletion. DMI ozone measurements have been used for validation of the Suomi-NPP.
Aerosol sun photometers (Aeronet) from NASA are installed in Thule, Sondre Stromfjord, Scoresbysund and Narsarsuaqin Greenland.
DMI has been involved in European projects on modelling aspects of the stratosphere-troposphere coupling, investigatingthe importance of a well-resolved stratospheric representation for modelling the tropospheric climate.DMI participated in European projects investigating the adverse and beneficial health effects of ultraviolet radiation (UVR) exposure and in Nordic projects, analysing timeseries of tropospheric ozone based on balloon borne ozone measurements from several Arctic locations. Lately DMI has also been involved in a COST project 1207, EUBREWNET.
The DMI participates in EUMETSAT’s Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring, developing operational UV-index products, based on satellite measurements of the ozone layer.
6.IMPLEMENTATION OF THE RECOMMENDATIONS OF THE 9th OZONE RESEARCH MANAGERS MEETING
Denmark has contributed to the research recommendation to better quantify trends in vertically resolvedozone data records over thepolar regions, in particular regarding tropospheric trends.
Denmark has contributed to the recommendation for continuation of ground-based stations with long-term records which is absolutely necessary toprovide a reliable baseline for trend estimation as well as too maintain stewardship of long-term surface UV records.
Denmark has been active in public information services about the development of the ozone layer.
7.FUTURE PLANS
National funding for ozone and UV monitoring in Denmark and Greenland was secured until the end of 2016. In 2017 the funding situation will be renegotiated.
Research efforts will be directed towards improved understanding of the role of stratospheric changes for tropospheric climate including the dynamical coupling between the troposphere and the stratosphere. It is intended to include a stratospheric representation in new developments of the EC-Earth model complex.
8.NEEDS AND RECOMMENDATIONS
It is considered important to monitor the recovery of the ozone layer at high latitudes during changing stratospheric climatic conditions (decreasing temperatures, changes in chemical composition, changes in stratospheric dynamics). Maintaining and running stratospheric monitoring stations in the Arctic and elsewhere is becoming an increasingly heavy burden on national funding sources and possibilities for direct funding of ground-based monitoring activities and data provision should be considered to be included in major international programmes such as the European Copernicus and considered as part of validation efforts for satellite missions by major space agencies.
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