IMPACTS OF CLIMATE CHANGE ON SEABED (NEARSHORE AND OFFSHORE)
Piers Larcombe
Centre for Environment, Fisheries and Aquaculture Science (Cefas), Pakefield, Lowestoft
Executive Summary
I would anticipate that the view from coastal and marine sedimentologists would be that no major changes in habitats are likely to result from changed physical processes, except in some coastal and estuarine circumstances where some subtle changes in sediment transport regimes might have a broad impact, for example at estuary mouths. Generally, below depths of 20 – 30 m, there would be little change anticipated from purely physical impacts. However, there would be the possibility of: subtle regional changes in the subtidal zone, where gradients in wave energy at the bed and sediment availability can be high, and near some oceanographic features where production of biogenic material and it’s incorporation into the sediments may be altered.
Level of Confidence
LOW
Generally, confidence is low-medium, as indicated in the supporting evidence. Work has been lacking, understanding weak, and cause and effect poorly demonstrated with respect to marine climate change.
The relationships between the basic physical drivers, sediment type, bio-geochemistry, eco-hydrodynamics etc and biology are relatively poorly understood, and poorly predictable at present.
As a result of the above, it is difficult at present to propose what might be measured to assess possible changes in physical habitats. Some work is needed to examine this.
Key sources of Information
Please acknowledge this document as: Larcombe, P. (2006). Impacts of Climate Change on the Sea Bed (nearshore and offshore) in Marine Climate Change Impacts Annual Report Card 2006 (Eds. Buckley, P.J, Dye, S.R. and Baxter, J.M), Online Summary Reports, MCCIP, Lowestoft, www.mccip.org.uk