The State of World Fisheries and Aquaculture 2020

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PART 3 
OUTLOOK AND EMERGING ISSUES
BOX 22
VULNERABILITY OF COUNTRIES TO CLIMATE CHANGE IMPACTS ON CAPTURE FISHERIES
Rising water temperatures and acidification are two 
of the primary mechanisms by which the process of 
climate change is impacting marine biodiversity
1
and 
affecting both the productivity and the distribution 
of marine fish stocks.
2
The scale and magnitude of 
these ecological changes are of crucial importance 
for those societies that are dependent on marine 
fisheries for their livelihoods.
3
To support management 
and mitigation of these impacts, FAO has conducted 
a preliminary study that assigns a climate change 
risk score to marine coastal States for which data on 
changes in catch potential up to 2050 are available. 
This score takes into account: (i) the outputs of models 
for predicting area-specific changes in catch potential; 
and (ii) a composite score derived from a selection of 
metrics measuring the State’s economic and nutritional 
dependence on marine capture fisheries, in addition to 
its overall level of economic and social development. 
The dimension that captures the projected change 
in catch potential is termed the 
impact
dimension, while 
the dimension that measures economic and social 
vulnerability is identified as the 
vulnerability
dimension 
(Figure A). Four versions of the scoring framework were 
generated, one for each set of predictions outputted by 
two models:
1. dynamic bioclimate envelope model,
2. dynamic size-based food web model,
under two greenhouse gas emission scenarios:
1. RCP2.6 (low emissions),
2. RCP8.5 (high emissions),
as described by Cheung, Bruggeman and Momme.
4
States with high projected increases under these 
model-scenario combinations are scored highly 
along the impact dimension, on a scale from 0 to 1. 
The vulnerability dimension, also scored from 0 to 1, is 
divided into three subcomponents:
1. Nutritional dependence, which includes also 
dependence on trade for fish supply, total 
dependence on fish for demographic-adjusted 
nutrient requirements and a dummy variable 
indicating whether a country is classified as a 
low-income food-deficit country (LIFDC).
2. Economic dependence on marine capture 
fisheries, calculated from the estimated value of 
capture fisheries production as a percentage of 
gross domestic product (GDP), the value of 
fisheries exports as a percentage of GDP and as 
a percentage of total commodity exports, and 
the percentage of the population employed in 
the marine fisheries sector.
3. Relative level of economic and social 
development. This is based on per capita GDP, 
a composite of the World Bank’s governance 
indicators and a dummy variable indicating 
whether a State is classified as a least 
developed country (LDC). 
A given State is then assigned a climate change risk 
score from 0 to 1 calculated as an average of that 
State’s impact and vulnerability scores. 
Although individual country scores inevitably vary 
across the different combinations of projection models 
and scenarios, it is possible to observe several common 
results across countries. The States identified as most at 

Fish in diet

Food insecurity

Social and economic

Governance indicator

Fish in GDP

Fish in trade

Fish in employment