Current and previous projects at middle atmosphere research

ICEPURE

UV service for Greenland

Monitoring of ozone and UV-radiation in Greenland

Satellite Application Facility (SAF) on Ozone and Atmospheric Chemistry Monitoring
Continuous Development and Operational Phase

CALISTO

Cirrus clouds and transport of water vapour in the tropical tropopause layer (FNU-Cirrus)

Global Earth-System Monitoring Using Satellite and In-Situ Data (GEMS)

Global Earth Observation and Monitoring (GEOMON)

Quantifying the climate impact of global and European transport systems (QUANTIFY)

Eumetsat Satellite Application Facility on Ozone Monitoring

Stratosphere-Climate Links With Emphasis On The UTLS (SCOUT-O3)

Subvisible cirrus clouds and their influence on transport of water vapour to the stratosphere.

Validation of ENVISAT Ozone and NO2 products using ground-based measurements in Greenland (VOUGE)

Chemical and Dynamical Influences on Decadal ozone change (CANDIDOZ)

Quantitative Understanding of Ozone losses by Bipolar Investigations (QUOBI)

Radiometer for Atmospheric Measurements at SUMMIT (RAMAS)

Impact of tropical convection on the upper troposphere and lower stratosphere at global scale (HIBISCUS)

Comprehensive Investigations of Polar stratospheric Aerosols (CIPA)

Mapping of Polar Stratospheric Clouds and Ozone Levels relevant to the region of Europe (MAPSCORE).

Polar stratospheric clouds and ozone depletion: The role in global climate change (PSC-Climate).

Aerosol/clouds microphysics and heterogeneous chemistry studies in the lower stratosphere by models and multi-intrument measurements.   (ACHIWE-MMM)

Application of ESA-ENVISAT satellite data for studies of the impact of polar stratospheric clouds on Arctic ozone depletion during climatological changing conditions.

In-situ analysis of aerosols and gases in the polar stratosphere: A contribution to the THESEO campaign. (PSC-analysis)

Modelling of the impact on ozone and other chemical compounds in the atmosphere from aeroplane emissions. (AEROCHEM-II)

Multi-Instrument Investigation of polar stratospheric cloud formation and heterogeneous chemistry. (POSTCODE).

Towards the prediction of stratospheric Ozone (TOPOZ)

Stratospheric aerosols and ozone in the northern and southern hemisphere (SAONAS)

ESMOS/Arctic: European Stratospheric Monitoring Stations in the Arctic (ESMOS/Arctic II).

Spring-to-Autumn Measurements and Modelling of Ozone and Active species (SAMMOA)

Improved understanding of stratospheric ozone loss by collaboration with the SAGE III Ozone Loss and Validation Experiment (EURO-SOLVE)

Early projects

ICEPURE: The impact of climatic and environmental factors on personal ultraviolet radiation exposure and human health

Bevillingsgiver: EC Framework Programme 7 ENV. 2008.2.1.5.

ICEPURE will determine the adverse and beneficial health effects of ultraviolet radiation (UVR) exposure.

Wristwatch dosimeters, that record levels of UVR, will be worn by volunteers to determine their individual exposure to sunlight over extended periods of time. Satellite and ground station data will be gathered to establish UVR levels at the locations where participants are wearing the dosimeters. The wristwatch dosimeter data will be combined with data from a diary that participants keep of their daily behaviour, along with satellite data (i.e cloud cover) and UV measurements taken on the ground. This combined data will be used to show the influence of behavioural, meteorological, environmental and cultural factors on an individuals UVR exposure. Participants in the study include farmers working in northern and southern Europe. They also include people on holiday in different situations such as on the beach and in snow situations when skiing as well as children on summer camp.

Using the personal exposure data combined with satellite and ground station data we will develop more accurate models to assess the impact of climate change on future UVR exposure to European populations.

The effect of UVR exposure on DNA damage and the bodies immune system will be determined. Furthermore, the relationship between UVR exposure and vitamin D status will be determined, thus enabling a direct correlation between risk factors and health benefits.

The role of the DMI is to take part in UV measements and provide satellite data. Using the personal exposure data combined with satellite and ground station data we will develop a personalized UVR exposure model in order to model personal UVR exposure of small or large population groups taking into account the population behaviour and culture.

An objective for the future, also for the DMI, is to develop a variant of the above model that is coupled to, or imbedded in, a regional climate model (HIRHAM) to better represent radiation in a climate model and for prediction of future UVR exposure related to a changing climate.

Project period: 1 February 2009 - 1 February 2012

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UV service for Greenland

ESA-Promote

Increased levels of ultra-violet (UV) irradiance as a consequence of the decrease in the protecting stratospheric ozone layer poses a threat to the health of humans, animals and plants. This threat is particularly large in the Arctic due to severe ozone depletion in the winter and spring time some years. A UV service for Greenland is presently not available, although the Arctic is a particularly exposed and vulnerable region. The UV service for Greenland is intended to contribute to two of the services in the PROMOTE-2 GMES Services for Atmospheric Monitoring: the UV information service and UV record service. The service will be based on a combination of earth observation data and ground based data from Greenland. The primary user of the service is the Greenlandic Ministry of Health under the Greenland Home Rule.

Project period: 1 September 2007 – 30. September 2009

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Monitoring of ozone and UV-radiation in Greenland

Danish Environmental Protection Agency

The state of the ozone layer and the level of surface ultraviolet (UV) radiation are monitored by the Danish Meteorological Institute with support from the Danish Environmental Protection Agency at three stations in Greenland: Pituffik (Thule Air Base), Kangerlussuaq (Sondre Stromfjord), and Illoqqortoormiut (Scoresbysund). The sites are primary and secondary stations within the Network for the Detection of Atmospheric Composition Change (NDACC). Total ozone columns are measured by Dobson and SAOZ instruments at Pituffik and by a Brewer instrument at Kangerlussuaq. Vertical ozone profiles are measured by balloonborne ozone sensors at Illoqqortoormiut and Pituffik. Surface UV is measured by a spectrophotometer at Pituffik, by the Brewer instrument at Kangerlussuaq, and by a CIE broad-band radiometer at Illoqqortoormiut. Data are reported to databases at NDACC and the World Ozone and UV-radiation Data Center (WOUDC) under the World Meteorological Organisation. Data are also displayed at the DMI web site.

Project period: 1 January 2007 – 31. December 2011

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Satellite Application Facility (SAF) on Ozone and Atmospheric Chemistry Monitoring
Continuous Development and Operational Phase

Eumetsat

Development of operational software and hardware for near real time UV clear sky fields.

DMI SAF operations and on-site documentation maintaining and to produce and disseminate agreed SAF product. Maintaining SAF and on-site external and internal interfacing (inc. adaptation to interfaces changes). DMI site operations and data dissemination activities. SW maintenance (inc. changes required due to operating system, compiler, version upgrades). Near Real Time NUV Quality Assurance. Perform validation of the NRTUV product against ground based UV-index measurements for several measuring sites twice a year. For a few sites include a daily comparison with ground based measurements, present the results immediately on the NUV webpage and include in the NRTUV output quality report file for the next day. Including a cloud cover correction to the NRTUV product. Based upon cloud cover forecasts and a simple correction factor. The cloud cover corrected UV-index to be presented along with the NRTUV product.

Project period: 1 March 2007 – 29. February 2012

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CALISTO

Danish Research Councils

This project aims to validate stratospheric observations of chemical compounds from new satellite instruments against ground-based observations from the high latitude stations in Greenland. The validation will be performed using data from ozone sonde launches, UV-visible spectrometer measurements and a newly installed microwave spectrometer at Summit on the Greenlandic ice sheet.

High quality observations are a key requirement for research on stratospheric ozone depletion and climate change. As a consequence of the Montreal protocol a turnaround of the increasing trends of ozone depleting substances in the atmosphere has been documented by observations. Following the Montreal protocol it is of primary importance to monitor the ozone trends carefully in order to see if this signal will propagate to the ozone layer as models predict. By comparing the observations with predictive models we will assess whether observed changes agree with our current understanding represented by the models.

Project period: 1 January 2005 – 31. December 2007

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Cirrus clouds and transport of water vapour in the tropical tropopause layer (FNU-Cirrus)

Danish Research Councils

The Danish Meteorological Institute participates in the largest European experimental research effort in the tropics for studies of transport of water vapour from the troposphere to the stratosphere. During summer 2006 a major balloon campaign takes place from Western Africa as part of the European Integrated Project, Stratosphere-Climate Links With Emphasis On The UTLS (SCOUT-O3, running 2004-2009). DMI participates in the EU-project by theoretical model analyses of field campaign observations, and we want to extend our participation to include experimental investigations during the planned field campaign. The objectives will be to contribute to the campaign by launches of balloon borne backscatter-, water vapour-, and ozone-sensors for measurements of cirrus cloud formation in the tropical tropopause layer and investigations of transport of water vapour into the stratosphere. The scientific goal is to improve the understanding of ice-nucleation and dehydration processes in the tropical tropopause layer, to improve on the link between microphysical models of cirrus clouds and larger atmospheric chemistry models, based on interpretation of results from the tropical field campaign.

Project period: 1 January 2006 – 30. September 2007

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Global Earth-System Monitoring Using Satellite and In-Situ Data (GEMS)

European Commission, FP6

The objective concerns the implementation of a global UV-monitoring system in ECMWF’s data assimilation. The tasks include a survey of available methods and data for aerosol and surface albedo in the UV range and validation of UV-products against ground based observations.

Project period: 1 March 2005 – 31. December 2008

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Global Earth Observation and Monitoring (GEOMON)

European Commission, FP6

Provision of groundbased SAOZ ozone data from Pituffik, Greenland

Project period: 1 January 2007 – 31. December 2012

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Quantifying the climate impact of global and European transport systems (QUANTIFY)

European Commission, FP6

A set of scenarios will be simulated using a cloud resolving model with spectrally resolved microphysics, the MPC-model of DMI. Special attention will be on heterogeneous freezing thresholds and nucleation rates. Homogeneous freezing will be represented as well. Simulated particle distributions will be analysed and optical properties will be calculated. Parameterisations of freezing thresholds and nucleation rates will be developed. The model will be modified to include parameterisations of homogeneous ice formation and of heterogeneous ice formation due to aviation and other anthropogenic aerosols and from natural aerosols. In addition, results will be examined in light of the contrail cirrus observations. The comparison with observations may lead to the need for improvements in model parameterisations.

Project period: 1 March 2005 – 28. February 2009

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Eumetsat Satellite Application Facility on Ozone Monitoring

Eumetsat

Development of operational software and hardware for UV clear sky fields from EPS data. Definition of the necessary hardware for near-real-time UV clear sky processing. Processing and archiving of UV clear sky data.

Project period: 1 April 2003 – 28. February 2007

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Stratosphere-Climate Links With Emphasis On The UTLS

The central aim of this research is to provide best scientific knowledge for international assessments on ozone depletion and climate change for the Montreal and Kyoto Protocols.  These protocols, and the associated energy, environment and emission policies, are of fundamental importance to European quality of life and competitiveness.  We are providing new knowledge to the EU and national governments to develop the European position in discussions related to the Protocols with policies for sustainable development.  SCOUT-O3 maintains the excellence of the European atmospheric science community and leads to further integration of its activities. SCOUT-O3 involves the research efforts of 59 partners and more than 100 scientific groups and takes full advantage of new and existing research facilities developed at the national level.

Reliable prediction of the future evolution of the ozone layer and surface UV is urgently required as a basis for informed decisions by European policy makers.  The state of the ozone layer over the next decades will depend on the interplay between climate change and the impact and evolution of ozone depleting substances such as CFCs.  The Montreal Protocol has successfully reduced emissions and atmospheric concentrations of CFCs, which should return to their pre-ozone hole concentrations by about 2050.  However, the ozone layer will most likely not return to its pre-ozone hole state and so the central question of the Montreal process – how and when will ozone and UV radiation recover as CFC concentrations fall? – remains.  Indeed, in order to provide essential advice to policy makers, the answer to that question is required within the next years.

The research in this ambitious integrated project is focused on strengthening the European predictive capability through improving the use of coupled chemistry/climate models (CCMs). An improved understanding of model performance is gained from on-going validation and comparisons from existing and new measurements.  Interpretation of the measurements is achieved using a variety of models operating on all spatial scales.

Lack of knowledge about the tropical stratosphere and upper troposphere is addressed through tropical field campaigns involving aircraft and balloons to investigate the detailed mechanisms by which air passes from the troposphere to the stratosphere.  New fundamental information about chemical and microphysical processes gained from laboratory studies will improve the models used to interpret these measurements.  Understanding of the larger scale importance is gained through analysis of satellite measurements (e.g. from ENVISAT and CALIPSO), meteorological analyses and other global fields.  

Denitrification in the polar vortices is being studied to remove one of the major uncertainties regarding polar ozone loss.  Better understanding of processes in the UTLS through modeling and data analysis and studies of the long-term variability in extratropical large scale transport are also being performed to improve long-term predictions of mid- and high latitude ozone and UV.  Past and present variability in UV radiation is determined using re-evaluated and quality controlled data sets.  Focussed studies involving measurements and modeling are used to improve understanding of how clouds and aerosols modify atmospheric radiation.  

The integration of process studies within a modeling framework will enable SCOUT-03 to analyse and predict the current status and future evolution of the ozone layer and surface UV-levels with high confidence.  A comprehensive range of scenarios is used in the CCMs to provide the basis for a comprehensive study of the evolution and feedback of the coupled chemistry / climate system.

Participants

University of Cambridge (coordinator)

More that 60 European partners, including DMI

Project period: 1 May 2004 – 30 April 2009

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Subvisible cirrus clouds and their influence on transport of water vapour to the stratosphere.

Danish Space Board

Atmospheric trace species of relevance for stratospheric ozone depletion and radiation balance are transported from the ground to the stratosphere through the tropical tropopause by deep convective systems. Measurements since the middle of the 1950’s of stratospheric water vapour concentrations have shown an increase of roughly 2 ppmv (parts per million by volume) which is a substantial increase compared to typical present values of 4-6 ppmv and corresponding to an increasing trend of about 1%/year. There are no solid scientific explanations for these increases in stratospheric water vapour concentrations. Water vapour plays a vita role, both for atmospheric chemistry and radiation in the upper troposphere and lower stratosphere (the UTLS region of the atmosphere). Water vapour can be regarded as a tracer but is more complex in the sense that the vapour condenses into clouds, and water is transported by the downward transport of cloud particles. In the tropical tropopause layer (TTL) around 17-18 km minimum temperatures often go below -90C which implies that not more than 1-4 ppmv H2O can enter the tropopause into the stratosphere, Dehydration processes in connection with cirrus cloud formation, which may have a controlling influence on water vapour transport to the stratosphere, are not quantitatively well described. Subvisible layers of thin cirrus with horizontal extensions of several hundred kilometers have been observed in the upper troposphere. Microphysical mechanisms which stabilise such cloud systems over long time scales and distances are unknown, but the optical properties of the clouds have big impacts on the radiative balance, and the cloud formation influence the transport of water vapour to the stratosphere.

As a supplementary experimental effort to microphysical cirrus modelling activities in the EU-project HIBISCUS, DMI will perform balloon-borne backscatter measurements of sub-visible cirrus in the tropical tropopause layer in a field campaign from Bauru, Brazil, in early 2004. These activities will be part of a large balloon field campaign within the HIBISCUS project, organised by the French Centre National d’Etude Spatiales (CNES), with instrumentation from many European research institutions. The over-all objectives of the campaign are to study the transport of a long range of atmospheric constituents into the stratosphere through convective processes in the TTL region, including the formation of cirrus clouds. The project will also incorporate extensive usage of data from ESA’s ENVISAT, in particular regarding validation of tropospheric satellite measurements. DMI has since 1990 had a close collaboration with the University of Wyoming concerning balloon-borne backscatter soundings in the arctic stratosphere for studies of polar stratospheric clouds.

Participants:

Danish Meteorological Institute

Project period: 1 Jan 2003 – 28 Feb 2005

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Validation of ENVISAT Ozone and NO2 products using ground-based measurements in Greenland (VOUGE)

Danish Research Councils, ESA research.

Objectives

This project aims to validate ozone profiles and total ozone and NO2 columns measured from instruments onboard the ESA satellite ENVISAT against ground-based measurements from the high latitude stations in Greenland operated by the DMI. The validation is performed by utilizing data from ozone sonde launches and spectrometer measurements at Pituffik/Thule, Illoqqortoormiut/Scoresbysund and Kangerlussuaq/Sdr. Strømfjord. The purpose of the validation is to contribute to the maturation of the ENVISAT data processors with particular emphasis on the many challenges at high latitudes. The validation is important in order to ensure high quality satellite measurements in the Arctic necessary for early observations of ozone depletion, trend detection and climatic impacts. The project supports the Danish engagement in the ENVISAT-AO project CINAMON (AO-ID 158).

Participants:

Danish Meteorological Institute, Denmark

Project period: 1 July 2002 -30 June 2005

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Comprehensive Investigations of Polar stratospheric Aerosols (CIPA)

European Commission, Energy, Environment and Sustainable Development Programme,

Contract no. EVK2-CT-2000-00095

Problems to be solved.

Climate models predict that increased concentrations of greenhouse gases may cause lower temperatures in the stratosphere and more widespread formation of polar stratospheric clouds (PSC). Results from chemical and optical PSC analyses will provide knowledge about PSC particle formation, required by atmospheric chemistry and microphysical models to calculate more reliable scenarios for the ozone layer in a future climate. The investigations aim strengthening the scientific base, needed to implement the European Union's environmental policy in support of the Montreal Protocol, by contributing to improved understanding of some basic physical and chemical processes in the atmosphere which have a strong influence on stratospheric ozone depletion.

Scientific objectives and approach

The objective is to obtain a detailed knowledge of the pathways to formation of different types of PSCs. This is accomplished by balloonborne measurements of particle chemical composition, size distributions, phase, and optical properties in combination with large-scale cryo-chamber experiments. The investigation combines three activities as an integrated research project: Field measurements, large-scale laboratory simulations, and microphysical and optical modelling. Balloon-borne experiments will be performed from Kiruna in winters 2000/2001 and 2001/2002 using multi-instrument payloads to measure the chemical and physical characteristics of PSC particles and their gas phase environment. The payloads consist of an aerodynamic focusing lens and a mass spectrometer for measurements of condensed H2O and HNO3, together with detection of dissolved trace gases. Optical particle counters provide particle concentration and size distributions, and backscatter sondes measure the backscatter ratio at four wavelengths and depolarisation. Physical phase and refractive indices of the particles are derived from these measurements. Finally, observations are made of near-gondola environment, especially temperature and water vapour. Nearly identical instrumentation will be used within a large cryo-chamber to perform simulations of PSC particle formation over a wide temperature and gas phase range. Temperature and the gas environment of the chamber will be monitored and changed, both systematically and in a way to simulate the particle evolution in connection with the balloon-borne observations. Over periods of hours and days, composition, size distribution, and phase of aerosols will be continuously measured. The meteorological conditions in connection with the balloonborne field measurements will be analysed by non-hydrostatic meteorological mesoscale model calculations, providing high-resolution temperature histories of the observed air parcels. Microphysical and optical models will be used to calculate the chemical compositions, physical phase, size distributions, and optical properties of PSC particles, which can be compared directly to the field and laboratory measurements.

Expected impacts

The investigations will provide measurements of the chemical composition of PSC particle, including dissolved content of trace gases together with information on particle volume and physical phase. Cryo-chamber simulations of PSC formation will characterise the condensed and gas phase. Microphysical model simulations and comparisons with the experimental results will lead to concluding recommendations for PSC microphysical and optical modelling, e.g. in terms of new pathways for particle formation, updated estimates on freezing and condensation rates, or refractive indices.

Participants:

Danish Meteorological Institute, Denmark (co-ordinator)

Max-Planck-Institut für Kernphysik, Germany

Forschungzentrum Karlsruhe, Germany

Laboratoire de Meteorologie Dynamique du Centre National de la Recherche Scientifique, France

Consiglio Nazionale delle Ricerche - Istituto di Fisica dell'Atmosfera, Italy

University of Wyoming, USA

Project period: 1 Oct 2000 - 3 Sep 2002.

cipa-report

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Mapping of Polar Stratospheric Clouds and Ozone Levels relevant to the region of Europe (MAPSCORE).

European Commission, Energy, Environment and Sustainable Development Programme,

Contract no. EVK2-CT-2000-00072

Detailed studies of solid PSC particle formation have been carried out in connection with mountain leewave cooling events, showing that indeed these phenomena could generate solid type PSCs. However, it is currently unclear to what extend the effects of solid type PSC formation in leewaves play on a hemispheric scale. Investigations have shown that solid type 1a PSCs exist at low temperatures for longer periods than liquid type 1b PSCs and thereby potentially could have experienced a larger probability of being affected by mountain leewaves. Analysis of type 1a PSC observations from NH locations where leewaves are not prevailing have shown that type 1a PSC could form early in the winter. This is difficult to explain because synoptic temperatures do not drop below the frost point that early in the season. However, upstream leewave events could have generated the solid type PSC particles.

The project sets out for a systematic study to investigate the effects from localised leewave cooling events on PSC properties on a hemispheric scale. A mountain wave cooling parameterisation, applying NH orography and analysed surface winds will be applied to investigate if specific trajectories, which potentially could have been influenced by upstream leewave events, carry information about solid type PSC generation which cannot be seen without the inclusion of the mountain wave parameterisation.

Radiosonde data offer a high-resolution view of stratospheric temperatures, which can be used to correct analysed temperatures like ECMWF's, which are used by many modellers. Many radiosonde stations are located close to mountain ranges and are influenced by lee-wave activity. In the present project it is planned to correct ECMWF temperatures according to the nearest radiosonde within, say, 100 km distance, and to quantify the effect on calculated PSC surface areas. The dense grid of domain-filling trajectory calculations would be used on different isentropes covering the heights where PSCs occur. If necessary, diabatic descent will be taken into account. Along the trajectories the microphysical model from DMI will be run. The advantage of this approach is threefold:

1. observed (not modelled) lee-waves are taken into account

2. possible biases in the ECMWF temperatures are corrected

3. small vertical scale temperature fluctuations are taken into account. ECMWF temperatures are averages over the whole model layer, and minimum temperatures are therefore often too high.

Erroneous radiosonde data are dealt with in the following way: Lee-wave affected radiosonde temperatures are used as is. Other radiosonde temperature deviations from ECMWF temperatures are disregarded if they differ more than some threshold temperature (TBD) from that of nearby radiosondes.

Domain filling trajectories will be calculated for selected past NH winters. The trajectories are initialised on a dense regular grid in mid-winter inside the polar vortex. The trajectories are calculated in a backward and forward model, spanning the whole PSC season. The temperature histories are used as input to the microphysical box model. The model calculates the time dependent PSC chemical compositions and size distributions and mixing ratios of H2O and HNO3, assuming an initial size distribution of background sulphate aerosols. The model applies the basic vapour diffusion equation to calculate the exchange of mass between the gas and condensed phase during particle growth and evaporation. The model simulates the growth and evaporation of type 1b PSC (STS particles); type 1a PSC particles (assumed to be composed of NAT) and type 2 PSC ice particles once the solid type particles are formed by homogeneous freezing of liquid type 1b PSC particles below the ice frost point.

Effects of mountain leewave events will be investigated in two ways. First, a parameterisation of mountain wave cooling, using NH orography and surface winds will be applied to trace those trajectories which could have been exposed mountain wave temperature depressions, possibly holding signatures of freezing and solid type PSC formation. Second, radiosonde data will be used to correct analysed temperatures like ECMWFs. Many radiosonde stations are located close to mountain ranges and are influenced by lee-wave activity. It is planned to correct ECMWF temperatures according to the nearest radiosonde to quantify the effect on calculated PSC surface areas. Finally, the uncertainties of the used temperatures will be estimated and the effects of the modelled PSC occurrences are assessed.

Signatures of liquid or solid PSC formation can be derived either from direct particle measurements or from the effects on the gas phase environment. Lidar depolarisation measurements will give an immediate measurement of the occurrence of solid type PSCs at the specific location of the lidar station or along the flight path of an airborne lidar. Satellite measurements of gas phase HNO3, together with temperature, will give an indication of larger-scale type 1a PSC formation. These particles, if composed of nitric acid trihydrate, take up significantly more nitric acid from the gas phase than liquid type 1b particles at the same temperature unless very close to the ice frost point temperature. Both types of measurements will be used for validation of PSC properties, calculated by the microphysical model from DMI and based on domain-filling trajectory calculations.

Participants:

University of Leicester, UK

Rutherford Appelton Laboratory. UK

Service d’Aéronomie du Centre National de la Recherche Scientifique, France

Cent.Nat. Res., Frascati, Italy

Deutsche Forschungsanstalt für Luft- und Raumfart, Germany

Alfred-Wegener-Institut für Polar- und Meeresforschung, Germany

Danish Meteorological Institute, Denmark

Belg. Inst. Space Aeronomy, Belgium

Belgian Univ.-Ges.hochschule,Belgium

Naval Research Lababoratory USA

University of Wyoming, USA

University of Leeds, UK

ETH, Switzerland

Project period: 1 Jan 2001 - 31 Dec 2003.

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Polar stratospheric clouds and ozone depletion: The role in global climate change (PSC-Climate).

Danish Research Councils, ESA research.

Results using global climate models show that increased concentrations of greenhouse gases, besides increasing tropospheric temperatures, also may lead to decreasing temperatures in the stratosphere. This project implies an investigation of climatological consequences of lower stratospheric temperatures on increased occurrence of polar stratospheric clouds (PSC) and thereby stronger ozone depletion. The project comprehends experimental and theoretical investigations, including the usage of data from ESA’s ENVISAT-1 satellite. The first pert of the project concerns balloonborne measurements of the chemical and physical properties of polar stratospheric clouds which are known to play a mandatory role for chemical ozone depletion. Results from the experimental investigations will be used to improve microphysical modelling of PSCs. In the second phase of the project the microphysical PSC-model will be coupled to chemical transport models (CTM). Global observations of stratospheric cloud formation and chemical tracers from ENVISAT will be used in CTMs for calculation of ozone depletion and compared to measurements of ozone from ENVISAT. In focus of this investigation will be the consequences for stratospheric ozone depletions due to lower stratospheric temperatures. The project constitutes the Danish contribution to the ESA-project ACHIWE-MMM.

Participants:

Danish Meteorological Institute, Denmark

Project period: 1 Oct 2000 -30 Sep 2003

psc-climate-report

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Application of ESA-ENVISAT satellite data for studies of the impact of polar stratospheric clouds on Arctic ozone depletion during climatological chnaging conditions (ENVISAT-Pilot).

Danish Space Board

The objectives of this pre-projekt has been to prepare proposals for the Danish National Science foundation and prepare the Danish participation in several international projects related to polar stratospheric clouds and Arctic ozone depletion. Furthermore to conduct studies for optical modelling of laser-backscatter sondes and methods for determination of PSC particles refractivi indices in collaboration with Istituto di Fisica dell'Atmosfera, IFA-CNR, Italy and the University of Wyoming, and to initialise a Ph.D. study of PSC at DMI.

Participants:

DMI

Project period: 1 December 1999- 31 December 2000

Final report (in Danish language)

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Aerosol/Cloud microphysics and Heterogeneous chemistry studIes in the loWEr stratosphere by Models and Multi-intrument Measurements.   (ACHIWE-MMM)

European Space Agency

The aim of the project is to combine atmospheric measurements of polar stratospheric clouds (PSCs) obtained from different instruments and atmospheric models to investigate PSCs formation and the heterogeneous chemistry involved in stratospheric ozone depletion. The proposal will involve the use of measurements from some ENVISAT instruments, which would provide aerosol and chemical data, from 2 Arctic, 2 Antarctic and 4 European lidar stations, and from in situ laser backscatter sonde and optical particle counter.A sampling satellite data along Lagrangian trajectories would allow the study of the evolution and decay of a PSC within given air parcels. The project would permit advancements in:

a description of the spatial scales of PSC properties,

the microphysical properties by polar stratospheric clouds,

the chemical processing within a polar stratospheric cloud,

improved chemical modelling in the lower stratosphere.

Participants

Istituto di Fisica dell'Atmosfera, IFA-CNR (co-ordinator)

University of Oxford, UK

University of l'Aquila, Italy

Rutherford Appelton Laobratory, UK

Service d’Aéronomie du Centre National de la Recherche Scientifique, France

Alfred-Wegener-Institut für Polar- und Meeresforschung, Germany

Danish Meteorological Institute, Denmark

Belgisch Instituut voor Ruimte-Aeronomie, Belgium

ACHIWE-MMM proposal

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In-situ analysis of aerosols and gases in the polar stratosphere:
A contribution to the THESEO campaign. (PSC-analysis)

European Commission, Environment and climate programme, Contract no. ENV4-CT97-0523

Objectives

The objective of the project is to obtain a complete and simultaneous characterisation of polar stratospheric cloud (PSC) particles in terms of their chemical composition and physical phase, particle size distributions, optical properties, and the ambient atmospheric conditions in which the particles form. By the complete particle characterisation the goal would be to improve the detailed microphysical modelling and thereby understanding of PSC formation.

Brief Description of the Research Project

The goals of the project will be accomplished through co-ordinated balloonborne and airborne experiments and by data interpretation, utilising meteorological, microphysical, and optical models. The project will constitute an integrated part of the Third European Stratospheric Experiment on Ozone (the THESEO campaign), and the field experiments will be performed in January 1999 and 2000 from Kiruna, Sweden.

In-situ measurements of the PSC characteristics will be obtained by different instrumentation onboard common balloonborne gondolas. The measurement of PSC particle composition requires a separation of the condensed phase from atmospheric gases without a change in particle properties. To accomplish this, a newly developed differentially pumped aerodynamic lens will be used, producing a beam of particles which enter a quadrupole mass spectrometer for composition analysis. An ion-molecule-reaction mass spectrometer will be used for the gas phase HNO3 measurements, and a cryogenic frostpoint-hygrometer for H2O concentrations, revealing if the condensed phase is in equilibrium with the vapour. Optical particle counters will be used for measurements of the particle size distributions, and combined optical measurements by backscatter sondes will be used for physical phase determination, and used to derive refractive indices and other optical properties of the particles.

An airborne lidar will be used for measurements of the spatial and temporal development of the PSCs, providing a three dimensional (horizontal and vertical) vision of the extent of the PSCs. The airborne lidar will be operated simultaneously with the balloonborne experiments, following the general trajectory of the balloon. Depolarisation measurements are obtained, providing an indication of the physical state of the observed particles.

The observed PSCs can be assumed to be formed in large-scale lee waves. DMI will provide a non-hydrostatic model to be used for simulation of the meteorological conditions in connection with the balloon- and airborne experiments. A microphysical model, describing type 1a, 1b, and type 2 PSCs, will also be provided by the DMI to simulate the evolution of PSC size distributions, their chemical compositions and physical phase, and the atmospheric conditions in which the particles form. The observational data will be used to constrain the microphysical model, and results from the field may lead to radical adjustments of the model in order to explain the observations.

Participants:

Danish Meteorological Institute, Denmark (co-ordinator)

Max-Planck-Institut für Kernphysik, Germany

Laboratoire de Meteorologie Dynamique du Centre National de la Recherche Scientifique, France

Consiglio Nazionale delle Ricerche - Istituto di Fisica dell'Atmosfera, Italy

Service d'Aeronomie du Centre National de la Recherche Scientifique, France

University of Geneva, Switzerland

University of Wyoming, USA

Project period: 1 Feb 1998 - 31 July 2000.

PSC-analysis final report

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Modelling of the impact on ozone and other chemical compounds in the atmosphere from aeroplane emissions. (AEROCHEM-II)

European Commission, Environment and climate programme, Contract no. ENV4-CT97-0621

Objectives

Emissions from aircraft (NOx, H2O, SO2 and soot) at cruising altitudes are likely to affect the ozone chemistry in the upper troposphere (UT) and the lower stratosphere (LS) in two ways: directly through enhanced photochemical activity (emission of NOx and water vapour), and through enhanced particle formation from NOx, water vapour and SO2. The impact of aircraft emissions is of particular importance to study, as the emissions are projected to grow rapidly over the next two decades compared to emissions from most other sources, and because there are significant regional differences in the impact on ozone and in the projected growth in the emissions. It is therefore likely that future aircraft emissions have the potential to perturb ozone levels significantly.

The overall objective of the study is to improve our scientific basis for estimates of the impact of aircraft emissions on the chemical composition in the UT and in the LS, and to perform 3-D model studies of the large scale (regional to hemispheric) perturbation of ozone from a projected future fleet of subsonic and supersonic aircraft.

Focus in the study will be on two main area: a) The role of heterogeneous processes in the UT and the LS and how these processes can be parameterized in global 3-D CTMs, and b) modelling studies of the future impact of subsonic as well as supersonic traffic on the ozone in the UT and the LS, with particular emphasis on the regional contribution to global scale ozone from regions with the largest projected traffic (Europe - US, South Asia and surrounding areas.

It is intended to use a microphysical model of the formation of Polar Stratospheric Clouds (PSC) from the DMI in larger 3D chemistry transport models for calculations particle surface areas, available for heterogeneous chemical reactions, and the magnitude of denitrification and dehydration.

The heterogeneous chemical reactions depend strongly on the nature of the particle surfaces (composition, liquid or solid) and on temperature. At the same time major changes in the particle properties, at least for the particles in the polar regions, occur in narrow temperature ranges, whereby a detailed particle simulation is required. Currently, there are still many uncertainties, in particular regarding the formation and composition of the solid type 1 PSC and the process of denitrification.

Studies on the effects from increases in air traffic on the PSC formation require modelling work by coupling of microphysical and 3D chemistry transport models. In this respect, work will address the develop parameterisations of the PSC particle formation to be used in larger atmospheric chemistry models. This work will also concern the possibility of running the microphysical module off-line the chemical-transport calculations in the larger model frameworks.

Participants:

University of Oslo, Norway (co-ordinator)

University of l'Aquila, Italy

Deutsche Forschungsanstalt für Luft- und Raumfart, Germany

Cambridge of University, UK

ONERA; Centre National de Recherches Meteorologiques, France

Max-Planck Institut für Chemie, Germany

Danish Meteorological Institute, Denmark

Norwegian Institute for Air Research, Norway

Project period: 1 May 1998 – 30 April 2000

DMI contribution to the final report

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Multi-Instrument Investigation of polar stratospheric cloud formation and heterogeneous chemistry. (Postcode).

European Commission, Environment and climate programme, Contract no. ENV4-CT97-0541

Objectives

The project takes a multi-disiplinary approach which seeks to unite stratospheric aerosol data and improved state-of-the-art atmospheric modelling tools in order to investigate polar stratospheric cloud (PSC) formation and the heterogeneous chemistry involved in stratospheric ozone depletion. The aim of the project is to provide information required for a better quantitative explanation of the present state of the ozone layer and its future evolution. The project involves the use of measurements from two Arctic and two Antarctic lidar stations, from an airborne lidar, from a novel in situ backscattering device, from an optical particle counter, and from instruments on the Upper Atmosphere Research Satellite (UARS). The use of such a disparate measurement data-set is innovative in that it will tightly constrain PSC formation and heterogeneous chemical modelling, and avoid biases that can be introduced in single instrument studies. Included in the project are fundamental laboratory measurements of the spectra of PSC particles essential to the interpretation of existing and proposed PSC data. The project aims to develop an innovative inversion algorithm to estimate key PSC properties including surface area density (which will be validated by lidar and in situ measurements) from infrared spectral measurements. A clear advance in this project is the sampling of high resolution satellite data along Lagrangian trajectories so that the evolution and decay of a PSC can be examined. In doing so the chemical changes within an airparcel are effectively decoupled from the dynamics allowing a clear picture of PSC formation and heterogeneous processing to be obtained. Quantitative understanding of stratospheric processes will be expressed within a numerical model of the atmosphere which includes the best possible descriptions of the important physical and chemical processes (PSC formation, heterogeneous processing, ozone depletion) obtained from fundamental laboratory and atmospheric studies.

The task of the DMI will be the development of an optical model for calculations of extinction and backscatter of PSC particles. The model will be used in comparisons of satellite, groundbased, and airborne measurements of PSCs with predictions from microphysical and optical model calculations for determination of refractive indices of PSC particles.

Participants:

University of Oxford, UK (co-ordinator)

Rutherford Appelton Laobratory, UK

Fondazione per la Meteorologia Applicata, Italy

Service d’Aéronomie du Centre National de la Recherche Scientifique, France

Deutsche Forschungsanstalt für Luft- und Raumfart, Germany

Alfred-Wegener-Institut für Polar- und Meeresforschung, Germany

Danish Meteorological Institute, Denmark

Belgisch Instituut voor Ruimte-Aeronomie, Belgium

Project period: 1 Mar. 1998 - 31 Feb. 2000

http://www.atm.ox.ac.uk/POSTCODE/

DMI contribution to the final report (PSC model description)

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Towards the prediction of stratospheric Ozone (TOPOZ)

Stratospheric aerosols and ozone in the northern and southern hemisphere (SAONAS)

European Commission, Environment and climate programme, Contract no. ENV4-CT95-00501) and ENV4-CT95-00902)

Objective:

A microphysical model, developed at the DMI, will be included and tested out in the 2-D model of the University of Oslo. The microphysical code is used to calculate the formation of polar stratospheric clouds (PSCs). Test will be completed to assess the sensitivity in ozone depletion to changes in HNO3 and H2O (from air plane emissions). and in temperature. The calculations will also include the sulphate particle formation in the microphysical code. The code is not presently included in the 3D CTM model, but will be tested out in connection with the project.

Participants:

1)

University of Cambridge, UK (co-ordinator)

Centre National de Recherches Meteorologiques, France

Max-Planck Institut für Chemie, Germany

UK Meteorological Office, UK

University of Oslo, Norway

2)

Finnish Meteorological Institute, Finland (co-ordinator)

CNR of Firenze, Italy

Freie Universität Berlin, Germany

University of Lyon, France

Observatoire Cantonal, Switzerland

University of l’Aquila, Italy

Univesity of Oslo, Norway

Danish Meteorological Institute subcontractor to University of Oslo.

Project period: 1. Mar. 1996 - 1. Mar 1998

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ESMOS/Arctic: European Stratospheric Monitoring Stations in the Arctic.

European Commission, Environment Programme, Contract No.: ENV4-CT95-0136

Objectives

In the European Arctic two research stations have been equipped during the last years with modern groundbased instrumentation for observation of stratospheric constituents. The stations in Thule/Greenland, operated by the Danish Meteorological Institute (DMI) and Italy and in Ny Ålesund/Spitsbergen, operated by Germany and Norway. They were only recently included in the global Network for the Detection of Stratospheric Change (NDACC) and constitute the European contribution to the "Arctic Primary Site" of NDACC. The objective of this project is to perform the full measurement programme required for NDACC stations and to improve the data analysis and interpretation in the field of stratospheric chemistry and ozone depletion. The measurements allow to describe the chemical composition and dynamics of the Arctic stratosphere. Data will be provided about the ozone concentration profile, stratospheric aerosols and other compounds like ClO, N2O, NOx, HCl, HNO3, ClONO2, CFCs.

Accordingly the following topics are in the scope of this project:

The evolution of the chemical composition of the Arctic stratosphere will be observed throughout the year to detect any so-called "perturbed chemistry" which initiates from chemical ozone depletion. This includes stratospheric aerosols like polar stratospheric clouds (PSC) or volcanic aerosols from Mt. Pinatubo.

Information on the dynamics of thr polar vortex will be deduced from available long-lived tracers, like volcanic aerosols or trace gases like N2O.

Special attention will be paid to exchange processes across the vortex boundary. The two stations are well located for these studies, as the vortex boundary is often found between them. The application of stratospheric models will help to analyze specific observations recorded during the project period.

Role and responsibilities of DMI

The work to be performed by DMI, based at the NDACC station at Thule, mainly focus on four scientific areas:

Ozone and Trace Gas data interpretation:

Continuous monitoring of the vertical ozone profiles by balloonborne ozone soundings and total ozone and NO2 concentrations by groundbased SAOZ measurements

Microphysical modeling, Backscatter Sonde Measurements and Analysis:

Experimental and theoretical studies of physical processes of polar stratospheric (PSC) and sulphate aerosols.

Meteorological data analysis:

Meteorological analysis of the dynamic state of the stratosphere.

UV-B radiation measurements:

Continuous groundbased UV-B irradiance measurements during day light periods.

Participants:

Alfred-Wegener Institut für Polar- und Meeresforschung, Germany (co-ordinator)

Danish Meteorological Institute, Denmark

Università degli Studi di Roma "La Sapienza", Italy

Universität Bremen, Germany

National Physics Laboratory, UK

Norwegian Institute for Air Research

Project period:

1 February 1996 – 31 January 1999

DMI contribution to the final report

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Spring-to-Autumn Measurements and Modelling of Ozone and Active species (SAMMOA)

Contract EVK2-CT-1999-00049

Participants

Abbreviation	Name of Institute/Country
NILU	Norwegian Institute for Air Research, Norway (Coordinator)
DMI	Danish Meteorological Institute, Denmark
UOX	University of Oxford, UK
ULEEDS	University of Leeds, UK
FZJ	Forschungszentrum Jülich, Germany
AWI	Alfred Wegener Institute - Potsdam, Germany
UCAM	Centre for Atmospheric Science, University of Cambridge, UK
IRF	Swedish Institute of Space Physics, Sweden