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Modelling


Relative fish stock in m Tonnes/year


0,8 0,7


0,6 0,5


0,4 0,3 0,2 0,1 0


74 52 74 58 43 40


10 30


2010 2030 2050 BAUBAU2G2


2010 2030 2050 2010 2030 2050


20 0


Figure 19: Fish stock relative to 1970 level (left axis) and fish catch (right axis) in BAU, BAU2 and G2 scenarios


to lead to 27 to 59 per cent higher employment level in the green scenarios relative to the baseline by 2050.24


On the other hand, additional BAU investments,


24. Employment in the fisheries sector, when adopting the alternative approaches proposed in the Fishery chapter (e.g. the reduction of fishing capacity will affect primarily large vessels and industrial production), will be reduced by only 1-1.2 million people in the short-term – as opposed to a loss of about 10 million direct jobs. In this case, employment in the fishery sector in the longer-term will be largely above the BAU scenarios.


53


in m Tonnes /year 74


Fish catch 63


70 80


60 50


40


assumed to be allocated to current business practices, will further deplete fish stocks, expected to be largely exploited by 2050 (it is estimated that only 56 per cent and 33 per cent of the fish available in 1970 will be in place by 2015 and 2050), leaving few resources for what could be currently considered cost-effective fish catch (Figure 19). Here again, the results indicate the need to offset transition costs in the short run to reach higher productivity and employment levels in the future under a green economy scenario.


To carefully evaluate the effectiveness of investments in the fishery sector, a variety of scenarios were simulated where the cost (effectiveness) of fish-stock management interventions are assumed at between US$ 354 and US$ 1,180 per ton (BAU is US$ 736, or a 1:4 ratio of cost/benefit), following a random uniform distribution.


The results of the corresponding


changes in fish stock and fish catch are presented in Figure 20.


In the two extreme scenarios, the global fish stock in 2050 will respectively return to the 1970 level (lowest cost case) and current level - around half of 1970 volume - (highest cost case). In the G2 scenario, around 70 per cent of the amount of fish resources in 1970 is available by 2050, which drops to a mere 30 per cent under BAU, where no additional stock management activities are assumed. As a result, the world fish catch will recover, after a short-term decline, to the relatively wide range of between 50 million tonnes and 90 million tonnes per year in 2050,


BAU


Stock ratio 2.0


1.5 1.0.0 0.5 0.5 0.0 2010 2020 2030 2040 2050


G2 (with confidence regions by colour) 50%


G2 (w 50%


(w 00


with confiden 75%


n


Fish catch (million tonnes)Fish catch ((million tonnes) 100


75% e


75 50 2 50 25 0 1990 2005 2020 2035


Figure 20: Results of the sensitivity analysis for (a) fish stock relative to 1970 level (left) and (b) fish catch in tonnes/year (right)21


21 Area in yellow: 50 per cent of the range of scenarios in the sensitivity analysis, green for 75 per cent, blue for 95 per cent and grey for 100 per cent. 2050


nce regions by colour) 95%


95%


100


100%


527


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