ASSESSING THE IMPACT OF CO2 EMISSION CONTROL SCENARIOS IN FINLAND ON RADIATIVE FORCING AND GREENHOUSE-EFFECT

Carbon dioxide emission reduction scenarios for Finland are compared w ith respect to the radiative forcing they cause (heating power due to the absorption of infrared radiation in the atmosphere). Calculations are made with the REFUGE system model using three carbon cycle models to obtain an uncertainity band for the development of the atmospheric concentration. The future emissions from the use of fossil fuels in Fi nland are described with three scenarios. In the reference scenario (b usiness-as-usual), the emissions and the radiative forcing they cause would grow continuously. In the scenario of moderate emission reductio n, the emissions would decrease annually by 1% from the first half of the next century. The radiative forcing would hardly decrease during t he next century, however. In the scenario of strict emission reduction s, the emissions are assumed to decrease annually by 3%, but the forci ng would not decrease until approximately from the middle of the next century depending on the model used. Still, in the year 2100 the forci ng would be considerably higher than the forcing in 1990. Due to the s low removal of CO2 from the atmosphere by the oceans, it is difficult to reach a decreasing radiative forcing only by limiting fossil CO2 em issions. The CO2 emissions from fossil fuels in Finland contribute to the global emissions presently by about 0.2%. The relative contributio n of Finnish CO2 emissions from fossil fuels to the global forcing due to CO2 emissions is presently somewhat less than 0.2% due to relative ly smaller emissions in the past. The impact of the nonlinearity of bo th CO2 removal from the atmosphere and of CO2 absorption of infrared r adiation on the results is discussed.