Climate change: impacts on our vision for commercially productive seas

© David Lees The impacts of climate change on the commercial services provided by our seas will be significant. Sea-level rise, coastal flooding and storms and waves will affect ports, shipping and built structures. Fishing and fish farming will be affected by temperature change and plankton availability. Rising temperatures should have positive impacts on tourism, whilst retreating Arctic sea-ice may open up new (seasonal) shipping routes.

The bold text indicates new information for the 2007–2008 report.

	WHAT IS ALREADY HAPPENING	WHAT COULD HAPPEN
Shipping Plymouth University	There are no academic studies available on the direct impacts of climate change on shipping, although numerous industry and media reports have been published in the past year. Climate change mitigation measures are having an indirect impact; in the short term, regulation of greenhouse emissions will arise through international agreement and a Greenhouse Gas Indexing Scheme for ships is being developed. Fuel efficiency and reduction of greenhouse gas emissions are driving a push for new propulsion and hull technology.	Major risks to ports are likely to arise from flooding and physical damage associated with sea-level rise and severe storms. Future changes in wind speed and storminess could lead to reduced loads, route changes and restrictions for some ships. Continued decline of Arctic sea-ice could extend accessibility to high-latitude shipping routes, for example increasing the Arctic navigation season from Europe to Asia from 20–30 days to 90–100 days per year within this century.
Tourism NE; University of Maastricht	Climate change is increasing the frequency of months when conditions are more comfortable for tourists in north-west Europe than in the Mediterranean.	A longer tourist season and increased visitor numbers to the north-west European coastal zone will lead to: increased tourist infrastructure (i.e. hotels, attractions, marinas); increased revenues; increased employment; increased waste (i.e. sewage, solid waste); and increased environmental damage.
Built structures Cefas	Allowances for annual rates of sea-level rise are made in the planning of coastal structures. Increases in wave heightsThe distance between the trough and peak of a wave. over the period 1973–1998 are part of the statistical measures that set the design criteria for oil and gas rigs.	Increasing rates of erosion under existing scenarios of climate change could increase damage to coastal structures by three to nine times within this century. The cabling infrastructure around wind farms may be particularly sensitive to changes in the supply and movement of sediment.
Fisheries Cefas; FRS; MBA	Excessive fishing pressure over many decades may have resulted in fish populations less able to ‘buffer’ against occasional poor year classes and the impacts of natural climate variability. Distribution shifts and modifications of fish behaviour as a result of temperature changes, may be affecting the vulnerability of certain fish stocks to fishing fleets.	In the short term, climate change will have little influence on fish stock recovery, which depends instead upon reducing fishing effort to allow existing year classes to survive to maturity. Long-term climate change may affect the overall productivity of fish stocks in a given area. Some species may be adversely affected leading to reductions in sustainable yield whilst others, for example seabass, red mullet and John Dory, may be positively affected leading to enhanced fishing opportunities.
Aquaculture (fish and shellfish farming) FRS	In the short term, climate change is unlikely to have a significant effect on UK-farmed marine fish (over 99% of which are cultivated in Scotland) and shellfish (39% in England and Wales; 43% in Northern Ireland; 18% in Scotland for 2006).	Rising water temperatures could increase growth rates for some species (e.g. Atlantic salmon, mussels and oysters), but may also cause thermal stress for cold-water species (e.g. cod and Atlantic halibut) and intertidal shellfish (e.g. oysters). New species (e.g. sea bass, bream) may be cultivated. Farmed species may become more susceptible to a wider variety of diseases as temperatures increase. Increasing harmful algal and jellyfish blooms may lead to additional fish kills and closure of some shellfish harvesting areas. Increased temperatures and more abundant plankton could also improve reproduction and settlement of ‘spat’ at shellfish farms.