Radiative Forcing Due to Anthropogenic Greenhouse Gas Emissions from Finland: Methods for Estimating Forcing of a Country or an Activity

The objective of this study was to assess the radiative forcing due to Finnish anthropogenic greenhouse gas emissions in three scenarios. All the Kyoto Protocol gases, i.e., CO₂, CH₄, N₂O, and fluorinated gases, were included. The calculations showed that forcing due to Finnish emissions will increase in the case of all gases except methane by the year 2100. In 1990, radiative forcing due to Finland's emission history of all Kyoto Protocol gases was 3.2 mW/m², of which 71% was due to carbon dioxide, 17% to methane, and the rest to nitrous oxide. In 1990 the share of fluorinated gases was negligible. The share of methane in radiative forcing is decreasing, whereas the shares of carbon dioxide and of fluorinated gases are increasing and that of nitrous oxide remains nearly constant. The nonlinear features concerning additional concentrations in the atmosphere and radiative forcing due to emissions caused by a single country or activity are also considered. Radiative forcing due to Finnish emissions was assessed with two different approaches, the marginal forcing approach and the averaged forcing approach. The impact of the so-called background scenario, i.e., the scenario for concentration caused by global emissions, was also estimated. The difference between different forcing models at its highest was 40%, and the averaged forcing approach appeared to be the more recommendable. The effect of background concentrations in the studied cases was up to 11%. Hence, the choice of forcing model and background scenario should be given particular attention.     

Greenhouse impacts of anthropogenic CH4 and N2O emissions in Finland

The Finnish anthropogenic CH₄ emissions in 1990 are estimated to be about 250 Gg, with an uncertainty range extending from 160 to 440 Gg. The most important sources are landfills and animal husbandry. The N₂O emissions, which come mainly from agriculture and the nitric acid industry are about 20 Gg in 1990 (uncertainty range 10–30 Gg). The development of the emissions to the year 2010 is reviewed in two scenarios: the base and the reduction scenarios.According to the base scenario, the Finnish CH₄ emissions will decrease in the near future. Emissions from landfills, energy production, and transportation will decrease because of already decided and partly realized volume and technical changes in these sectors. The average reduction potential of 50%, as assumed in the reduction scenario, is considered achievable.N₂O emissions, on the other hand, are expected to increase as emissions from energy production and transportation will grow due to an increasing use of fluidized bed boilers and catalytic converters in cars. The average reduction potential of 50%, as assumed in the reduction scenario, is optimistic.Anthropogenic CH₄ and N₂O emissions presently cause about 30% of the direct radiative forcing due to Finnish anthropogenic greenhouse gas emissions. This share would be even larger if the indirect impacts of CH₄ were included. The contribution of CH₄ can be controlled due to its relatively short atmospheric lifetime and due to the existing emission reduction potential. Nitrous oxide has a long atmospheric lifetime and its emission control possiblities are limited consequently, the greenhouse impact of N₂O seems to be increasing even if the emissions were limited somehow.     

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 with 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 Finland are described with three scenarios. In the reference scenario (business-as-usual), the emissions and the radiative forcing they cause would grow continuously. In the scenario of moderate emission reduction, the emissions would decrease annually by 1% from the first half of the next century. The radiative forcing would hardly decrease during the next century, however. In the scenario of strict emission reductions, the emissions are assumed to decrease annually by 3%, but the forcing would not decrease until approximately from the middle of the next century depending on the model used. Still, in the year 2100 the forcing would be considerably higher than the forcing in 1990. Due to the slow removal of CO₂ from the atmosphere by the oceans, it is difficult to reach a decreasing radiative forcing only by limiting fossil CO₂ emissions. The CO₂ emissions from fossil fuels in Finland contribute to the global emissions presently by about 0.2%. The relative contribution of Finnish CO₂ emissions from fossil fuels to the global forcing due to CO₂ emissions is presently somewhat less than 0.2% due to relatively smaller emissions in the past. The impact of the nonlinearity of both CO₂ removal from the atmosphere and of CO₂ absorption of infrared radiation on the results is discussed.     

Resource Consumption and Environmental Impacts of the Agrofood Sector: Life Cycle Assessment of Italian Citrus-Based Products

Food production and consumption cause significant environmental burdens during the product life cycles. As a result of intensive development and the changing social attitudes and behaviors in the last century, the agrofood sector is the highest resource consumer after housing in the EU. This paper is part of an effort to estimate environmental impacts associated with life cycles of the agrofood chain, such as primary energy consumption, water exploitation, and global warming. Life cycle assessment is used to investigate the production of the following citrus-based products in Italy: essential oil, natural juice, and concentrated juice from oranges and lemons. The related process flowcharts, the relevant mass and energy flows, and the key environmental issues are identified for each product. This paper represents one of the first studies on the environmental impacts from cradle to gate for citrus products in order to suggest feasible strategies and actions to improve their environmental performance.

Landscape design,planning, and management: An approach to the analysis of vegetation

The process of analyzing vegetation in terms of its suitability for various non-consumptive uses is primitive in comparison with systems for evaluating other resources such as soil and topography. This paper proposes a framework for developing a standardized, quantitative vegetation analysis system based on plant ecology methods. A tentative scheme under study in Wisconsin is presented for discussion purposes.     

Analyzing the Impacts of Dams on Riparian Ecosystems: A Review of Research Strategies and Their Relevance to the Snake River Through Hells Canyon

River damming provides a dominant human impact on river environments worldwide, and while local impacts of reservoir flooding are immediate, subsequent ecological impacts downstream can be extensive. In this article, we assess seven research strategies for analyzing the impacts of dams and river flow regulation on riparian ecosystems. These include spatial comparisons of (1) upstream versus downstream reaches, (2) progressive downstream patterns, or (3) the dammed river versus an adjacent free-flowing or differently regulated river(s). Temporal comparisons consider (4) pre- versus post-dam, or (5) sequential post-dam conditions. However, spatial comparisons are complicated by the fact that dams are not randomly located, and temporal comparisons are commonly limited by sparse historic information. As a result, comparative approaches are often correlative and vulnerable to confounding factors. To complement these analyses, (6) flow or sediment modifications can be implemented to test causal associations. Finally, (7) process-based modeling represents a predictive approach incorporating hydrogeomorphic processes and their biological consequences. In a case study of Hells Canyon, the upstream versus downstream comparison is confounded by a dramatic geomorphic transition. Comparison of the multiple reaches below the dams should be useful, and the comparison of Snake River with the adjacent free-flowing Salmon River may provide the strongest spatial comparison. A pre- versus post-dam comparison would provide the most direct study approach, but pre-dam information is limited to historic reports and archival photographs. We conclude that multiple study approaches are essential to provide confident interpretations of ecological impacts downstream from dams, and propose a comprehensive study for Hells Canyon that integrates multiple research strategies.     

Use of Remote Sensing Techniques to Determine the Effects of Grazing on Vegetation Cover and Dune Elevation at Assateague Island National Seashore: Impact of Horses

The effects of grazing by feral horses on vegetation and dune topography at Assateague Island National Seashore were investigated using color-infrared imagery, lidar surveys, and field measurements. Five pairs of fenced and unfenced plots (300 m²) established in 1993 on sand flats and small dunes with similar elevation, topography, and vegetation cover were used for this study. Color-infrared imagery from 1998 and field measurements from 2001 indicated that there was a significant difference in vegetation cover between the fenced and unfenced plot-pairs over the study period. Fenced plots contained a higher percentage of vegetation cover that was dominated by American beachgrass (Ammophila breviligulata). Lidar surveys from 1997, 1999, and 2000 showed that there were significant differences in elevation and topography between fenced and unfenced plot-pairs. Fenced plots were, on average, 0.63 m higher than unfenced plots, whereas unfenced plots had generally decreased in elevation after establishment in 1993. Results demonstrate that feral horse grazing has had a significant impact on dune formation and has contributed to the erosion of dunes at Assateague Island. The findings suggest that unless the size of the feral horse population is reduced, grazing will continue to foster unnaturally high rates of dune erosion into the future. In order to maintain the natural processes that historically occurred on barrier islands, much larger fenced exclosures would be required to prevent horse grazing.