Climate change is one of the most important future drivers of changing fish distributions, ecosystem productivity. This is likely to influence the distribution and fishing patterns of fishing fleets and the socioeconomics of fishing. Along with collaborators, I am interested in the effects of climate change and fishing on the distribution of fishes and the structure of temperate and tropical fish communities.
Deepening of North Sea fishes
The North Sea has warmed by 1.6oC in the last quarter century. We recently uncovered coherent deepening of the North Sea fish assemblage. While individual species are moving northward, some are moving southward, due to the peculiar hydrography and bathymetry of the North Sea. However almost everything is moving deeper tracking the deepening isotherms.
Relative vulnerability of national economies to the effects of fishing
Which countries have most to gain and which have most to lose from the effects of climate change on their fisheries? This is a question most development agencies and policy makers want answered. However it is difficult to answer using the traditional scientific approach. Ideally one would know how each element of climate change – rainfall, sea temperature, primary production, salinity – affects all components of (1) the life cycles and population dynamics of fishes and invertebrates, (2) the distribution and interactions of species and (3) eventually their catchability and availability to fishing fleets. One would also like to know how climate-induced disasters and disease outbreaks are likely to affect fishing communities and their capacity to target and catch fishes and invertebrates. Finally one might also like to know how burgeoning human populations are going to affect the distribution of incomes and the likelihood of migrants to enter fisheries.
Clearly this is a lifelong research agenda for hundreds of scientists!
So we used a vulnerability framework to approximate the biological and socioeconomic complexity. The potential impact depends on the degree of exposure to physical climate change and the intrinsic sensitivity or dependency of economies to changes in fisheries. Ultimately the vulnerability depends on the degree to which the potential impact can be offset by adaptive capacity of nations -0 the degree to which they can anticipate and cope with challenges. Adaptive capacity is a nebulous construct but depends on GDP, education levels and the strength of governance among other things.
The short answer is that while most climate change is happening in the most northerly countries, these countries have the greatest capacity to anticipate the impact. Instead the national economies of tropical countries, particularly in Africa are most likely to be affected by the effect of climate change on their fisheries.
Clearly this work is just the beginning. I am involved in two further projects that will take this work forward.
Quest-Fish
http://web.pml.ac.uk/quest-fish
QUEST-FISH will focus on investigating how climate change would affect the potential production for global fisheries resources in the future, compared to past and present scenarios, in the absence of exploitation.
This approach removes uncertainties as to what exploitation regulations will be implemented in coming decades, and focuses on the added impacts that climate change is likely to cause, and on the subsequent additional risks and vulnerabilities to human societies.
The global-scale impacts of climate change: QUEST-GSI
http://web.pml.ac.uk/quest-fish/
Key aim of QUEST-GSI:
The key aim of QUEST-GSI is to better quantify the impacts of climate change in a consistent way across the entire globe, and for a range of sectors such as: water resources, flooding, crops and human health.
The project is part of Theme 3 of the NERC funded QUEST programme.
Informing climate policy
Climate change impacts studies to date typically consider particular regions and sectors and use a wide range of socio-economic and climate scenarios. This makes it difficult to assess impacts at the global scale and to compare impacts for different socio-economic and climate futures. Furthermore it makes it difficult to assess the effectiveness of proposed policy measures to reduce greenhouse gas emissions and so reduce the impacts of climate change.
Key questions
- What are the global-scale impacts for different levels of global temperature change?
- How are the impacts in different sectors interrelated?
- Where are the “hot spots”?
- How much will climate change mitigation and adaptation policies reduce “damages”?
Key aspects of the QUEST-GSI project
- Improved quantification of impacts and uncertainty
- Consistent analysis across different sectors and across the globe
- Interlinkages between the sectors
- Consideration of adaptation and vulnerability
