Scientific Bulletin of the Electrical Engineering Faculty – Year 10 No. 1 (12) ISSN 1843-6188 APPLICATION OF A GLOBAL MODEL TO THE STUDY OF ARCTIC BASIN POLLUTION C. NITU1, Vladimir F. KRAPIVIN2, Anda S. DOBRESCU1 University Politehnica of Bucharest, Splaiul Independenţei, nr. 313, 060042 V.A. Kotelnikov Institute of Radioengineering and Electronics, Russian Academy of Sciences, 1 Vvedensky sq., Fryazino, Moscow region, 141190 E-mail: cnitu_ubp2001@yahoo.com 1 2 northwestern Siberia, coal and gold extraction in Yakutia and Chukot as well as the mining industry on the Kola Peninsula have led to a strong anthropogenic intervention into the natural environment. Plant cover has been violated over great territories, the area and productivity of reindeer pastures diminished and the hydrologic regime of rivers disturbed. The greatest quantities of pollution substances are brought to the northern coast of Russia by the rivers, violating the ecosystems of the northern seas. Further adverse influence on the Arctic ecosystems can lead to rising regional or even global scale negative consequences. Thus the problem of the development of the northern territories of Russia, the United States of America, Canada and the Scandinavian countries needs to be solved by careful analysis of all types of ecosystem dynamics, by real time data collection and formation of national databases and by defining effective ways to coordinate development of the natural and anthropogenic processes. Abstract: The arctic basin pollution has some specific characteristic in comparison with other seas because of the lower temperatures and slower biologic processes. An understanding of the environmental processes in the Arctic regions, which is a prerequisite for finding scientific solutions to the problems arising there, can be found only by combining many disciplines, including ecology, oceanography, mathematical modeling, and system analysis. This paper synthesizes data from many sources and knowledge from various scientific fields in the form of a Spatial Simulation Model of the Arctic Ecosystem (SSMAE). Keywords: spatial simulation model, model of the Arctic ecosystem 1. INTRODUCTION The purpose of this study is to develop and to investigate a simulation model of the pollution dynamics in the Arctic basin. It is known that the ecosystems of the Arctic seas are vulnerable to a considerable extent in comparison with the ecosystems of other seas. [6] The processes that clean the Arctic Ocean are slower and marine organisms of the Arctic ecosystem live in a polar climate where the vegetation period is restricted. Some feedback mechanisms have significant time delays and the capacity of the ecosystem to neutralize the effects of human activity is feeble. Apart from these reasons the Arctic ecosystem has specific boundary conditions connected with the sea-ice ergocline which reduce its survivability level. 2. ARCTIC BASIN POLLUTION PROBLEMS The Arctic region plays a unique role in the global environmental processes, forming numerous adverse correlations with the Earth’s climatic system. Low temperatures, a high level of atmospheric circulation and the availability of large ice-covered aquatories are notable for the high latitudes, quite unlike the other areas of the globe. In the figure 1, it is presented the geographical localization of the Arctic region. [7] The intensive industrial development of the northern territories has led to significant environmental change in these regions, especially in the Russian territories. Oil and gas extraction on the Yamal and Taimir peninsulas in Figure 1. The geographical localization of the Arctic region The purpose of this study is to develop and to investigate a simulation model of the pollution dynamics in the Arctic basin. There are many experimental and theoretical results giving estimates of the growing dependencies between the pollution dynamics in the World Ocean and the state of the continental environment. The problem of the Arctic basin pollution causes the most anxiety to investigators [2]. It is known 111 Scientific Bulletin of the Electrical Engineering Faculty – Year 10 No. 1 (12) that the ecosystems of the Arctic seas are vulnerable to a considerable extent in comparison with the ecosystems of other seas. Processes that clean the Arctic Ocean are slower and marine organisms of the Arctic ecosystem live in the polar climate where the vegetation period is restricted. Some feedback mechanisms operate with significant time delays and the capacity to neutralize the effects of human activity is feeble. Apart from these reasons the Arctic ecosystem has specific boundary conditions connected with the sea-ice ergocline which reduce its survivability level. In connection with this circumstance, the Arctic basin is the object for investigations in the frameworks of many national and international environmental programs. [4] The research strategies of these programs include the theoretical and experimental study of the tundra ecosystems, Siberian rivers and near-shore and open arctic waters. The main problems arising here consist of determining a set of the principle matters that are necessary to study in the first place. These include the following: Transport modeling of pollutants in the arctic ecosystems. Modelling of the exchange processes of carbon dioxide and methane between the tundra ecosystems and the atmosphere. Modelling of the hydrological regime and estimation of the pollutant flows in the Arctic Basin. Modelling of the Arctic ecosystems under conditions of anthropogenic impacts. Modelling of the biogeochemical carbon cycle in the “Atmosphere/Arctic Ocean” system. Development of a complex model for the functioning of the hydrologic and biogeochemical systems in Arctic. Stability estimation of the Arctic systems under variable global climate conditions. ISSN 1843-6188 3. SSMAE STRUCTURE A conceptual diagram and the block contents of the SSMAE are shown in Figure 2 and Table 1. The functioning of the SSMAE is supported by the global model of the nature-society system (GMNSS) and by the climate model (CM). The SSMAE inputs are the data about the pollutant sources of the near-shore Arctic Basin, the ice areas and the current maps. The SSMAE contains three types of blocks: mathematical models of the natural ecological and hydrophysical processes, service software and the scenarios generator. The marine biota block (MBB) describes the dynamics of the energy flows in the trophical chains of the Arctic Basin ecosystem. The hydrological block (HB) describes the spatial discretization of on the water circulation in the Arctic. The pollution simulation model (PSM) contains the anthropogenic scenarios and the service control block (SCB) provides for the control of the simulation experiment. An understanding of the environmental processes in the Arctic regions, a prerequisite for finding scientific solutions to the problems arising there, can be found only by combining many disciplines, including ecology, oceanography, mathematical modeling, and system analysis. [5] This paper synthesizes many data sources and knowledge from various scientific fields in the form of a Spatial Simulation Model of the Arctic Ecosystem (SSMAE). The basic blocks of the SSMAE are oriented on the description of the dynamics of any given pollutant. For consideration of a specific pollutant it is necessary to include in the SSMAE an additional block with the description of its physical and chemical characteristics. This procedure is demonstrated by examples of blocks that simulate the characteristics of radionuclides, heavy metals and oil hydrocarbons. The consideration of these pollutants is restricted to elements with averaged properties. The Arctic basin aquatory, , which is studied in this chapter has boundaries which include the peripheral Arctic seas as well as the coast line and southern boundaries of the Norwegian and Bering Seas. Figure 2. Block-diagram of the SSMAE . Descriptions of the blocks are given in Table 1.The Page Setup Dialog Box (Margins) for formatting a paper in MS Word xx. Table 1. Description of the SSMAE blocks (Figure 2) Block MBB HB PSM SCB APM MFB 112 Description of block Marine Biota Block containing the set of models for energy flows in the tropical chains of the Arctic basin ecosystem. Hydrological Block describing the water circulation in the Arctic seas and the movement of ecological elements. Pollution Simulation Model of the Arctic basin including the set of anthropogenic scenarios. Service Control Block to manage the simulation experiment Air Pollution transport Model. Model of the Functioning of the Biota under the conditions of energy exchange the tropical chain of the Arctic Basin ecosystem. Scientific Bulletin of the Electrical Engineering Faculty – Year 10 No. 1 (12) ISSN 1843-6188 Block SS MWD MMT IM NM MPT MOT MPR MRF MWS MEF MWT ICI ICD ICV - τu - summer, - τa - autumn. The procedure of spatial discretisation is provided for via the ICI block of the SSMAE database, including the set Description of block Simulator of Scenarios describing the ice fields, the synoptic situations and changes in the hydrological regimes. Model for the Water Dynamics of the Arctic Basin. Model for heavy Metals Transport through the food chains. The Illumination Model. The Nutrients Model. Model for Pollution Transport through water-exchange between the Arctic Basin and the Atlantic and Pacific Oceans. Model for the process of Oil hydrocarbon Transport to the food chains. Model for the Process of Radionuclide transport to the food chains. Model of River Flow to the Arctic Basin. Model of Water Salinity dynamics. Model for Energy Flow transport in the Arctic Basin ecosystem. Model for calculating the Water Temperature. Interface for Control of the Identifiers. Interface for Control of the Database. Interface for Control of the Visualization. of identifiers Ak aij , where k is a specific symbol to identify a real element of ij in the computer memory. Identifier A1 reflects the spatial structure of the 1 Arctic basin and adjoining territories ( aij 0 for ij; a 1 for ij when ij belongs 1 ij to the land (islands). Identifier A2 shows the position of the cells R, P, N, S, and describes the spatial distribution of the pollutant sources. Other identifiers Ak are used to describe ice fields (k=3), the spatial distribution of solar radiation (k=4) and the dislocation of upwelling zones (k=5). The user of the SSMAE in free-running mode may choose different ways to describe the many input parameters. Blocks ICI and ICD realize the on-line entry to Ak and to the database. For example, if the user has data about the spatial distribution of ice fields in , he can form identifier A3 with surface, aij3 0 for an ice-free water aij3 1 for new ice and aij3 2 for old ice. In this case block SS enables the input of data from the climate model concerning the ice fields. The block structure of the SSMAE is provided for with a C++ program. Each of the blocks from Table 1 is a C++ function. The main function provides the interactions between the SSMAE, SGM and CM. This functional specification supports overlapping output and input streams of the SSMAE blocks. With the conversational mode the user can toggle the data streams between the slave blocks. The calculating procedure is based on the subdivision of the Arctic basin into boxes {ijk}. This is realized by means of a quasi-linearization method [3]. All differential equations of the SSMAE are substituted for in each box ijk by easily integrable ordinary differential equations with constant coefficients. The water motion and turbulent mixing are realized in conformity with current velocity fields which are defined on the same coordinate grid as the {ijk}. Let us designate the Arctic basin aquatory as where and are latitude and longitude, respectively. Spatial inhomogeneity of the Arctic basin model is T CO2 provided by the set of cells with latitude and longitude steps of and , respectively. These cells are the basic spatial structure of for the realization of the computer algorithms. The cells ij are heterogeneous as to their parameters and functioning. There are a set of cells which are adjacent to the river mouths (R) and to the ports (P), bordering on the land ( ), in the Bering Strait (S) and on the south boundary of the Norwegian Sea (N). The aquatory is divided in depth z by step z. The distribution of depths is given as the matrix H = h ij where h ij = H( i ,λj), ( i ,λj) ij. As a result, the full water volume of is divided into volumetric 4. SIMULATION RESULTS compartments ijk = z|ii+1; jj+1; zk zzk+1} aijk The SSMAE allows for the estimation of the pollution dynamics of the Arctic basin under various a priori suppositions about the intensities of the flows of pollutants and under other anthropogenic impacts on the ecosystems of this region. The thermal regime of the Arctic basin is given by a normal distribution with average temperatures and with dispersions on the aquatories which are given by the SEDAAR (Strategic Environmental Distributed Active Archive Resource). The scheme of transport of pollutants in the atmosphere is adopted from Christensen [1]. The estimates of parameters for the blocks of Table 1 are given by literature sources or personal recommendations. The vertical distribution of pollutants in the initial moment t0 is taken as homogeneous. The average diameters of the (1) with volumes ijk =ΔφiΔjΔzk. Within ijk the water body is considered as a homogeneous structure. The water temperature, salinity, density and biomass of the compartments ijk are described by box models. The anthropogenic processes on the aquatory are described for the four seasons: - τw - winter, - τs - spring, 113 Scientific Bulletin of the Electrical Engineering Faculty – Year 10 No. 1 (12) solid particles are estimated to be in the range from 0.12 m to 1000 m and the vertical velocity of sedimentation is 0.003 m/s. The concentration of nutrients in the ice and snow equals 0. Also it is supposed that the deep water temperature t, = 0C and the surface ice temperature f1(t,,)=-3 C for ( It is supposed that the phytoplankton productivity in the ice layer is 2.5 percent of the primary production in the water column. Let the ratio between solid and dissolved phases of heavy metals at the moment t = t0 equal 1:2. The flows of heavy metals are described by linear models. The boundaries of the Norwegian and Bering Seas are approximated by lines with N = 62 oN and B = 51 oN, respectively. Simulation results include: The dynamics of Arctic Basin radionuclear pollution. The dynamics of Arctic Basin pollution by heavy metals. The dynamics of Arctic Basin pollution by oil hydrocarbons. Figure 3 gives example of simulation results. The Ob and Yenisey rivers are considered to be the main sources of radionuclear pollution, heavy metals and oil hydrocarbons for the Kara Sea. Figure 3 shows the influence of the river flow on the volume of pollutants transported by the Kara Sea aquageosystem to the Central basin. As shown by curves 1 and 2, the transference of heavy metals and radionuclides from the Ob and Yenisey rivers through the Kara Sea aquageosystem to the Central aquatories of the Arctic basin amounts to 2.1 percent when the river flow varies from 500 to 1000 km3/yr and after that it begins to grow linearly up to 7.6 percent for 2000 km3/yr. Hence, there is a critical level of pollution for the Kara Sea ecosystem beyond which it does not have time to dilute the flow of heavy metals and radionuclear pollutants. ISSN 1843-6188 In the figure 3, the interval [F1,F2] between the dashed lines corresponds to the range of variations of F in the real world. Curves 1 and 2 show concentrations of the heavy metals and radionuclides, respectively, at the point with , = 75oN, 65oE in the northwestern part of the Kara Sea. Curves 3 and 4 show the concentrations of heavy metals and radionuclides, respectively, at the point with , = 72oN, 150oW above the Alaskan North Coast 5. CONCLUSIONS An understanding of the environmental processes in the Arctic regions, which is a prerequisite for finding scientific solutions to the problems arising there, can be found only by combining many disciplines, including ecology, oceanography, mathematical modeling, and system analysis. This paper synthesizes data from many sources and knowledge from various scientific fields in the form of a Spatial Simulation Model of the Arctic Ecosystem (SSMAE). Simulation results include: The dynamics of the Arctic basin radionuclear pollution. The dynamics of Arctic basin pollution by heavy metals. The dynamics of Arctic basin pollution by oil hydrocarbons. Influence of the Arctic Sea ecosystems upon the dynamics of the pollutants in the seawater. Dependence of the pollutant concentration at different geographical points as a function of the flow of the Siberian Rivers to the Arctic Basin. 6. REFERENCES [1] Christensen, J.H. The Danish Eulerian hemispheric model a three-dimensional air pollution model used for the Arctic. Atmospheric Environment, 1997, 31(24), 4169 4191. [2] Krapivin V.F. and Varotsos C.A. Biogeochemical Cycles in Globalization and Sustainable Development. Springer/Praxis, Chichester UK, 2008, 562 pp. [3] Nitu. C., Krapivin, V. and Bruno, A. Intelligent techniques in ecology. Printech, Bucharest, 2000, 150 pp. [4] Nitu C. and Dobrescu A.S., Process control with energy reduction, Ed. .MATRIX, Bucharest, 2009, 164 pp. [5] Bobylev P. L., Kondratyev Ya. K., Johannessen M. O., Arctic Environment Variability in the Context of Global Change, Ed. Springer - Praxis Publishing, 2003, 470 pp [6] Wadhams P., Dowdeswell J A, Schofield A. M., Arctic and Environmental Change, Ed. The Royal Society, 1996, 197 pp [7] Van Vleet C, Amazing Arctic and Antarctic, Ed. Nomad Press, 2008, 130 pp Figure 3. Dependence of the concentrations of heavy metals ( + e) and radionuclides ( = 137Cs + 60Co) at different geographical points as a function of the flow (F) of the Ob and Yenisey rivers to the Kara Sea. 114