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Models - in short

Air pollution models

Information on models developed by us:


THOR refers to multi-scale modelling from hemispheric scale to street scale using a coupling of the air pollution models of DEHM, UBM and OSPM. THOR is an important modelling chain with many applications e.g. mapping of air quality at many locations, air pollution epidemiological studies, impact assessment of policy measures and operational 3-day air pollution forecasts.


Human Exposure Modelling to Traffic Air Pollution. DEHM/UBM/AirGIS is aGIS-based human exposure modelling system for traffic air pollution for application in air pollution epidemiological studies, human exposure studies, as well as urban air quality assessment and management. The recently added "DEHM/UBM" in the beginng of the name indicates the close coupling with the regional DEHM model and the Urban Background Model (UBM) providing background concentration and meteorology as input for OSPM.


EVA (Economic Valuation of Air Pollution) is a model system to calculate health effects and related external costs of air pollution. The model system can be used at different scales – e.g. for Europe based on the chemical transport model DEHM (Danish Eulerian Hemispheric Model), or for Denmark with high geographic resolution (1 km x 1 km) based on the local-scale air quality model UBM (Urban Background Model) that is coupled to DEHM.


Atmospheric dispersion model. OML is an operational short-range model for regulatory applications.


OML-Highway is a GIS-based model for assessment of air quality along motorways and other main roads in open terrain. 


OSPM (Operational Street Pollution Model) is a street canyon model. It can be used to assess air pollution from traffic in streets.

DEHM (in Danish)

DEHM – the Danish Eulerian Hemispheric Model - is a state-of-the-art chemical transport model. It is used, i.a. within the Danish national air quality monitoring programme for assessment of nitrogen deposition, and for assessments of air pollution transport to the Arctic. It also forms a component within the THOR system for air pollution forecast and the human exposure modelling system DEHM/UBM/AirGIS.


DAMOS is a model system for calculating the deposition of atmospheric nitrogen in nature. The NOVANA monitoring program routinely uses DAMOS.

The system is a combination of DEHM, which describes the nitrogen transported long and OML-DEP, which describes the marketing of the locally produced ammonia, which mainly comes from local agricultural sources.


The Urban Background Model (UBM) is a model used for calculating the background air pollution over Denmark with high resolution (1 km x 1 km). The model is e.g. used for air quality forecast and is included in the National Air Quality Monitoring Program. In addition, the model has been used in many consultancy projects and in research projects, e.g. for estimating health effects of air pollution as part of the DEHM/UBM/AirGIS exposure modelling system.


"Danish Rimpuff and Eulerian Accidental release Model" is a comprehensive, three-dimensional tracer model, which has been developed for studying transport, dispersion, and deposition of air pollution caused by a single but strong source, as e.g., the Chernobyl accident.

COPREM - a receptor model

COPREM (COnstrained Physical REceptor Model) is a receptor model that can be used for source apportionment. It unifies qualities from factor analytic models and chemical mass balance models.

Deposition calculations  (in Danish)

DEHM is used for routine computations of deposition of nitrogen and sulphur in Denmark. Computations with a high resolution are performed for selected areas in Denmark using OML-DEP - a variant of the OML model.