Possible Economic Impacts of a Shutdown of the Thermohaline Circulation: an Application of FUND

Climate change can lead to a substantial reduction of the strength of the thermohaline circulation in the world oceans. This is often thought to have severe consequences particularly on the North Atlantic region and Northern and Western Europe. The integrated assessment model FUND is used to estimate the extent of these impacts. The results indicate that, owing to a slower warming (rather than cooling) of the regions most affected by a thermohaline circulation collapse, climate change induced damages in these regions would be smaller in case of a shutdown of the thermohaline circulation. However, even with a thermohaline circulation collapse, the total and marginal impacts of climate change are negative.climate change, climate change impacts, thermohaline circulation, integrated assessment

Economic impacts of changes in population dynamics of fish on the fisheries in the Barents Sea

A bioeconomic simulation model of the two interacting fish species cod (Gadus morhua) and capelin (Mallotus villosus) and their fisheries is presented and applied to assess the consequences of changes in the population dynamics of these important fish stocks in the Barents Sea. In each scenario, the population dynamics of the fish species are changed by an external reduction of the reproductive rates and/or the carrying capacities. The stock sizes and landings of fish are calculated for each fishing period and the net present values of profits from fishing are determined for time periods prior to and after the change in population dynamics. Results show that reduced growth rates or carrying capacities both lead to lower stock levels and consequently to smaller catch sizes. There is only a small short-term economic impact on the fisheries but the long-term consequences are quite pronounced. In some cases, a higher fishing activity in the first few years after the change in population dynamics causes harvest sizes to remain stable despite diminishing stock sizes. This stabilizes the returns from fishing in the short run but veils the apparent negative long-term impact on the fisheries resulting from adversely affected stock dynamics.Barents Sea, bioeconomic modeling, capelin, cod, population dynamics

The economic impact of a shutdown of the Thermohaline Circulation: an application of FUND

The integrated assessment model FUND 2.8n is applied in an analysis of the overall economic consequences in a scenario of a shutdown of the thermohaline circulation (THC). Monetized market and non-market impacts of changes in environmental conditions following a THC collapse are determined for 207 individual countries. Eight different response patterns can be identified. The dominant pattern is that a THC shutdown has an offsetting effect on the underlying warming trend. Depending on whether the impacts of warming are initially beneficial or detrimental, the economic effects of a THC collapse show distinct regional variability. Key economic sectors affected in a THC shutdown scenario are water resources and energy consumption, as well as cardiovascular and respiratory diseases among health impacts. The maximum, national impact of a collapse of the THC turns out to be of the magnitude of a few per cent of GDP, but the global impact is much smaller. Considering the low probability of occurrence, a THC shutdown does not call for drastic action at present.Fisheries, climate change