Atmospheric Supply of Nitrogen, Lead, Cadmium, Mercury and Dioxins/Furans to the Baltic Sea in 2004

	Authors: Jerzy Bartnicki - MSC-W of EMEP e-mail: jerzy.bartnicki@met.no Alexey Gusev - MSC-E of EMEP e-mail: alexey.gusev@msceast.org Wenche Aas - CCC of EMEP e-mail: wenche.aas@nilu.no Hilde Fagerli - MSC - W of EMEP e-mail: hilde.fagerli@met.no

Introduction 

The first EMEP Centres Joint Report for HELCOM was delivered in 1997 (Tarrason et al. . 1997) and was followed by five annual reports (Bartnicki et al. 1998, 2000, 2001, 2002, 2003, 2004, 2005). Present EMEP Centres Joint Report for HELCOM is focused on the year 2004. It is based on the modelling and monitoring data presented to the 30th Session of the Steering Body of EMEP in Geneva in September 2005.

Following decisions of the 8th HELCOM MONAS Meeting held in Riga in 2005, the main deliverables expected from the EMEP Centres are the Indicator Fact Sheets for nitrogen, heavy metals and PCDD/Fs. These Indicator Fact Sheets include time series of emissions and depositions of selected pollutants, and are presented in Appendices C – H. In this report we present additional important information about emissions, depositions and source allocation budgets for nitrogen, heavy metals and PCDD/Fs in the year 2004.

The EMEP Unified Eulerian model system has been used for all nitrogen computations presented here. This system has undergone a major overhaul the last three years, where the previous EMEP models (Lagrangian as well as Eulerian) have been merged and rewritten in order to produce the Unified EMEP Eulerian model. The model has been documented in detail in EMEP Status Report 1/2003 Part I (Simpson et al. 2003) and in EMEP Status Report 1/2004 (Tarrasón et al., 2004). It has been verified against measurement data at EMEP stations for nine different years (1980, 1985, 1990, 1995-2000) in EMEP Status Report 1/2003, Part II (Fagerli et al. 2003). Following standard procedure, unified model results have been compared with the available measurements at the EMEP stations in 2003 (Tarrasón et al., 2005; 2006).

Atmospheric input and source allocation budgets of heavy metals (cadmium, lead, and mercury) to the Baltic Sea and its catchment area were computed using the latest version of MSCE-HM model. MSCE-HM is the regional-scale model operating within the EMEP region. This is a three-dimensional Eulerian model which includes processes of emission, advection, turbulent diffusion, chemical transformations of mercury, wet and dry depositions, and inflow of pollutant into the model domain. Horizontal grid of the model is defined using stereographic projection with spatial resolution 50 km at 60º latitude. The description of EMEP horizontal grid system can be found in the internet (http://www.emep.int/grid/index.html). Vertical structure of the model consists of 15 non-uniform layers defined in the terrain-following s-coordinates and covers almost the  whole troposphere. Detailed description of the model can be found in EMEP reports (Travnikov and Ilyin, 2005) and in the Internet on EMEP web page http://www.emep.int under the link to information on Heavy Metals.

Evaluation of PCDD/F atmospheric input to the Baltic Sea and its catchment area was carried out using the latest version of MSCE-POP model. MSCE-POP model is a threedimensional Eulerian multimedia POP transport model. The model is operating within the geographical scope of EMEP region with spatial resolution 50 km at 60º latitude. Vertical structure of MSCE-POP is defined similar to MSCE-HM model. MSCE-POP considers the following compartments: air, soil, sea, vegetation and forest litter fall. The model includes the following basic processes: emission, advective transport, turbulent diffusion, dry and wet deposition, gas/particle partitioning, degradation, and gaseous exchange between the atmosphere and the underlying surface (soil, seawater, vegetation). Detailed description of MSCE-POP model is given in EMEP report (Gusev et al., 2005) and in the Internet on EMEP web page http://www.emep.int under the link to information on Persistent Organic Pollutants.

Meteorological data used in the calculations for 2004 were obtained using MM5 meteorological data pre-processor on the basis of the Re-analysis project data prepared by the National Centers for Environmental Predictions together with the National Center of the Atmospheric Research (NCEP/NCAR) in the USA (web address: http://wesley.ncep.noaa.gov/reanalysis.html).

As decided by HELCOM all depositions, as well as, source allocation budgets have been calculated for the six sub-basins and catchments of the Baltic Sea. Names and acronyms of these regions, often used in the report are given below:

1. Gulf of Bothnia (GUB)

2. Gulf of Finland (GUF)

3. Gulf of Riga (GUR)

4. Baltic Proper (BAP)

5. Belt Sea (BES)

6. The Kattegat (KAT)

Depositions and source allocation budgets have been also calculated for the entire basin and the entire catchment of the Baltic Sea.

According to HELCOM requirements, the present annual joint report includes mainly figures and tables describing emissions, depositions and source allocation budgets for nitrogen, heavy metals and PCDD/Fs.

This report has been prepared for the Helsinki Commission, Baltic Marine Environment Protection Commission, based on the model estimates and monitoring results which have been presented to the thirtieth session of the Steering Body of EMEP (Co-operative Programme for Monitoring and Evaluation of Long-Range Transmission of Air Pollutants in Europe). This present, eighth joint summary report for HELCOM includes the measurements and results of modelling in the Baltic Sea region for oxidized nitrogen, reduced nitrogen, lead, cadmium, mercury and dioxins/furans for the year 2004. It has been developed in a frame of close collaboration between three modelling and monitoring EMEP centres: MSC-W, MSC-E and CCC, and is available now on the EMEP WEB pages and later on the HELCOM WEB pages. The report, as a draft, was presented and discussed at the Ninth MONAS Meeting (2-6/10/2006) in Silkeborg Denmark, together with corresponding drafts of the Indicator Fact Sheets. Participants of this meeting were asked for the comments and corrections which are taken into account in the final version of the report and Indicator Fact Sheets, as well. All comments/corrections received form the HELCOM Parties are listed on this site. Any additional comments should be sent to Jerzy Bartnicki or co-authors, preferably by e-mail.

Acknowledgements. The authors are indebted to the scientific teams at MSC-E, MSC-W and CCC for providing the results included in this report and especially to Per Helmer Skaali for his help with the Internet related tasks. We are grateful to Ms. Marina Varygina, Dr. Ilia Iliyn and Prof. Victor Shatalov for their contribution to this work, valuable remarks and comments.

For further information, please contact the authors:

Jerzy Bartnicki - MSC-W of EMEP e-mail: jerzy.bartnicki@met.no
Alexey Gusev - MSC-E of EMEP e-mail: alexey.gusev@msceast.org
Wenche Aas - CCC of EMEP e-mail: wenche.aas@nilu.no
Hilde Fagerli - MSC - W of EMEP e-mail: hilde.fagerli@met.no