The Content of the Project

This page is under development and will show more information following the practical work with the project

The interested reader can just scroll down the page and get an overview of the technical content of the project. Links to more detailed information is provided along the scroll.

If you want to jump directly to a certain part, please just click on the appropriate link below.

Please note that all pictures are possible to enlarge by clicking on them.

Air Quality Modelling
Internet Based Application System including Modelling Examples and Emission Database handling
Ambient Air Quality Monitoring Stations
Meteorological Measurement Equipment
Passives Sampler Campaigns
Laboratory Equipment

Air Quality Modelling

Several types of models are included, they serve various purposes.
  • Wind model

  • Langrangean / Gaussian model

  • Grid model

  • MATCH model

  • Heavy gas model

  • Street canyon model

  • Receptor model

Some of the models are discussed and demonstrated below.

Internet Based Application System

The Internet Airviro is based on the fact that many customers, like the EERC, are looking for applications which make use of the Internet for decentralization of work and responsibilities.

One corner stone is that only ONE application installation is needed (in the Central Office).
Users at the Central Offices access via the Local Area Network (LAN).
County (regional) Offices access via the Internet utilizing a standard PC and an Internet connection. No additional application/software installations are needed at the County Offices.

Another corner stone is that all applications are run (computed) in the Central Server at the Central Office. This means that only one powerful server is needed, but in this case it is duplicated. for back-up and other reasons.

Service & Maintenance as well as upgrades are consequently easily accomplished only in the Central Server via direct access by the supplier.

The Internet Airviro is LINUX based. LINUX operating system is nowadays becoming the standard for Government systems especially when it comes to web servers.


The Administration of the monitoring Stations is done from the Central System.

Picture 1:
The stations are interactively placed on the map.

Picture 2:
The station parameters are chosen such as presentation units; graph limits; alarm limits; formal data checks; etc.

Picture 3:
Communication parameters are chosen such as protocol (almost any protocol can be handled in the system); dial-up time; etc.

Picture 1:

Picture 2:

Picture 3:


The Data Analyses are carried out in Indico Presentation.

The user's login will set which stations (databases) the user can access. This also opens for external users to access the I-Airviro system.

The window handling is according to standard. Any window can be copied, printed, and used in any MS Windows based application like MS Word.
Several windows with various results (graphs) can be displayed at the same time.
The time scale on the x-axis and the value scale on the y-axis can easily be zoomed in and out.

The output can be
1) graphs,
2) pdf (e.g. for distribution),
3) text (ASCII).

The screen dumps show:

Picture 1: Menu for choosing the station: parameters; time period; graph type, etc. In this case a standard time series is displayed.

Picture 2: Two stations are chosen (Tallinn and Vilsandi). NOX is chosen as parameter to be displayed. A frequency and distribution graph is presented. (Please note the significant difference between the pollution levels in Vilsandi - a background station, and Tallinn - a city station.)

Picture 3: So-called Breuer diagrams are displayed. They show the level of pollution in relation to the wind direction. In this case - for Kohtla-Järve - it is clear that there is a significant increase of pollution levels of H2S and SO2 at the monitoring station when the wind is blowing from the southeast. This indicates a strong source of these pollutants while PM10 is a more general pollutant in the area.

Picture 4: The graphs can be displayed in many ways and various result windows can be displayed at the same time.

Picture 1:

Picture 2:

Picture 3:

Picture 4:


The Emission Database (EDB) is the crucial input for dispersion modelling, but can also be used for emission estimations of various kinds.

The user's login will set which databases the user can access. This also opens for external users to use the I-Airviro system.

The map handling allows for the use of various maps on any scale (zoom in/out and pan). This allows for a stepwise development of the application once additional County Offices enter into the project.

The map choice is followed by the choice to show the source on the map and/or as a listing (edit mode). Then the source(s) can be edited (added, changed, deleted) interactively.

The same principles are used for point, line, area, and grid sources.

The Search Criteria allows for extraction of the data from the EDB in various ways.

Printing of results uses standard MS Windows functions.

The EDB in Estonia

The EDB for Estonia consists of several hundreds of point sources, line sources (streets and roads), and area sources (like harbours). The following screen dumps show some examples of how the EDB works:

Picture 1: The main point sources - with a pre-defined minimum emission - are displayed on a map and as a listing.

Picture 2: To input the emission sources the map and/or coordinates can be used. The picture shows some point sources in an industrial area in Tallinn. Please note the big white spot which is the source used below.

Picture 3: The administrative information is given.

Picture 4: The technical information like compounds; stack height; emission and emission variation (according to a scheme "formula"); etc is given as parameters.

Picture 5: Using search criteria the user can use practically any combination of criteria to retrieve information from the EDB. The picture displays the search criteria NO2 for the whole of Estonia. The result is displayed as dots for each source and the total emission is calculated.

Picture 6: The same principles are used for area and line source (roads/streets). The picture shows the streets in central Tallinn (the white lines).

Picture 7: The roads/streets are interactively chosen on the screen. The chosen road link is lit up and ready for editing. New road links are added using the same principle.
This detailed screen dump is from P

Picture 8: In order to make as accurate emission estimates as possible, it is important to input accurate information (data) about the source. For the road/street information about the number of vehicles; type of street; number of lanes; vehicle type distribution; etc.


As an interesting parallel and reference, the regional Air Quality Management cooperation in the Stockholm Region has created one of the largest distributed EDBs in the world (48 local authorities of various sizes). For a comprehensive presentation of the regional cooperation in the Stockholm Region please download the Adobe pdf presentation from the study visit at Stockholm Environment and Health Protection Administration (SLB·analys) on 22 March 2005.

Picture 1:

Picture 2:

Picture 3:

Picture 4:

Picture 5:

Picture 6:

Picture 7:

Picture 8:


Several types of Dispersion Models are integrated in the system.

The models will need map, topography, roughness, meteorology/climatology, and - of course - emission information.

  • Wind Model

  • Langrangean / Gaussian Model

  • Grid Model

  • MATCH Model

  • Heavy Gas Model

  • Street Canyon Model

  • Receptor Model

The EDB is naturally used as input to the modelling of the more complex "what-if scenarios".

Picture 1: The results from a standard Gaussian Model (a simulated stack in Tartu) are displayed. 

There are several ways of presenting the results allowing  a way that suits all kinds of situations like scientific; decision-makers; media; or general public.

Pictures 2, 3, and 4: The three screen dumps to the right show the results from a Grid Model calculation over Tallinn area for NO2 from traffic at 7 am, 9 am, and 11 am respectively one morning.

The EDB is used as input for a scenario with several hours of meteorological data in a sequence.

Picture 1:

Picture 2: (The picture is around 1.5 MB.)

Picture 3: (The picture is around 1.5 MB.)

Picture 4: (The picture is around 1.5 MB.)


The Street Canyon Model provides a simulated view of the ambient air concentrations given parameters like street width; distance between buildings; height of buildings; etc.

The emissions can be either given directly (as in this case) or be estimated from the Emission Database.

The meteorological parameters can also be given directly (as in this case) or be fetched from the database.

The simulated results in the street canyon are presented together with the map. (Please note the detailed level of the map in the central part of Tallinn.) The results can also be run as a Time Series.


The Heavy Gas Model is mainly intended to be used for planning of consequences of accidents and the best actions to take to limit these consequences.

The model is also possible to use as a real-time application, but this takes a lot organisational arrangements and very accurate monitoring of the input.

The user provides as accurate input as possible about the accident (emissions parameters). The location of the accident is marked on the map. In a real-time case some kind of "standard" accident could be used.

The application fetches the relevant meteorological parameters from the closest meteorological station; calculates a wind field; and displays the dispersion plumes in time steps (in this case 10 minutes after the accident).


For a more comprehensive presentation of the Internet Airviro, please download the PowerPoint presentation from the seminar in Narva 10 March 2005. This presentation was used as an introduction to the project.

Ambient Air Quality Monitoring Equipment

Three new monitoring stations are measuring
  • SO2
  • NOX
  • O3
  • BTX (Benzene, Toluene, Xylene)
  • PM 10 / 2.5
  • TSP


The existing and new monitoring stations look more or less the same. These two pictures are from a monitoring station (Õismäe) in Tallinn located in a residential area.

Meteorological Measurement Equipment

The meteorological equipment is measuring

  • Ultrasonic Anemometers - (x, y, z) wind components
  • Differential temperature
  • Temperature
  • Humidity
  • Precipitation

and transmitting the information to the central computers.

Three 24-meter masts provide input to large scale modelling.

The first picture shows the principle design.

The second picture shows the installation of the equipment in a GSM mast. More pictures from the installation can be found in the Pictures from the Project pages.


More information about the ultrasonic wind measurement equipment is found on this link:

Passives Sampler Campaigns

Passive Samplers are used to cover large areas with a cost-effective measurement method. The Passive Samplers provide an average ambient air quality level over one - four weeks (depending on the compound measured and the concentrations).

The pollutant is transported to the sorbent by molecular diffusion.

The samplers are placed in suitable locations about three meters above ground. The pictures show

Around 145 samplers were used in the four nation-wide campaigns.

The following compounds were measured

  • SO2

  • NO2

  • VOC

The samplers were prepared (pictures 1, and 2) and then placed at sites with various conditions (pictures 3, 4, 5, and 6).
(The pictures from the Passive Samplers Campaign are a courtesy of
Madis Kõrvits.)

The report from the Passive Sampler Campaign can be found here.

More information about the Passive Samplers is found on this link:

Picture 1:

Picture 2:

Picture 3:

Picture 4:

Picture 5:

Picture 6:

(Can you find the sampler?)

Laboratory Equipment

The following laboratory equipment has been delivered:
  • Chromato-mass detector for organic pollution determination

  • High performance liquid chromatograph (HPLC) and UV detector (ketones + aldehydes)

  • Heavy metal detection equipment ICP (air + precipitation)

The new equipment enables the EERC to even further develop its skills and capabilities in various kinds of tests and analyses.








Computers necessary for the implementation and future use of the applications have been delivered.

Servers, workstations, desktops, laptops, monitors, and printers of various kinds are included.






A large amount of training has been accomplished during the project.

All kinds of users have been trained on their level of knowledge with the aim to prepare them for future work with the equipments and applications. Some parts of the training have been accomplished by experienced Estonian staff to facilitate a more local adaptation and understanding.

The Guestbook is meant to be a place for spontaneous reactions, more comprehensive comments, and questions. It will be more interesting for others if you write something in the Guestbook - so please do!

If you have a link to another website that you think would be beneficial for people visiting this website - please send it to me and I might include it on this page. Then we can set up links to each other for the benefit of everybody.

Up ] [ Content ] Presentations ] Pictures ]

Please send us an e-mail with your comments, views, questions, etc!
For normal mail address, telephone and fax, please click here! Updated: 18 March 2007