MARINE SCIENCE AND CLIMATE CHANGE

  Climate change is one of NERC's three current strategic priorities, but questions about the impacts of climate change on the marine environment (and vice versa) are being addressed under all three priorities. Examples of questions being investigated by NERC-funded researchers are given below.

STRATEGIC PRIORITY 1:  EARTH'S LIFE SUPPORT SYSTEMS

What are the sources, sinks and transportation processes of carbon within the Earth system?

  The ocean contains around 95% of the world's mobile carbon. Small changes in either annual inputs of carbon dioxide (CO2) to, or outputs from, the ocean result in much larger changes in atmospheric levels, with consequent implications for climate change. Studies of the dynamic behaviour of ocean circulation, chemistry and biology are critical to reducing uncertainty in global climate modelling.

  The build-up of CO2 in the oceans has made surface waters more acidic than they have been for millions of years. Ocean acidification is likely to continue, and NERC expects to make the study of its effects a priority in the Earth-system-science approach in its emerging strategy.

  NERC marine carbon processes work extends from remote satellite modelling studies, to determine large-scale ocean dynamics, through to experimental sea-going studies, to sample in specific areas and interfaces. These studies encompass the coast and open ocean examining both the upper ocean and sea bed processes. The most relevant are included in the programmes of CASIX, PML, SAMS and NOCS.

What is the role of biodiversity in ecosystem function, and what are the consequences of biodiversity loss on ecosystem processes, particularly those involving micro-organisms?

  Work is being carried out to assess how changes in biodiversity can be detected and measured together with studies on what functional consequences would result from change. These studies extend from the genetic level to whole organisms, such as marine mammals, and cover a broad geographical scope extending to the polar regions.

  The M&FMB programme has contributed significantly to this area, as are programmes at BAS, MBA, PML, SAMS and SMRU. Long-term surveys carried out by SAHFOS have shown dramatic changes in the pelagic systems of the North Atlantic in recent decades, with northerly movement of cold-water plankton without their replacement by warm-water species.

STRATEGIC PRIORITY 2:  CLIMATE CHANGE

How has the climate changed in the past, and how will it change in the future? How can we separate natural climate change from that caused by the activities of humans? Will long-term gradual change predominate, or can we expect to see abrupt climate change at the regional scale?

  Much work has been carried out on oceanographic variability and the interactions between the atmosphere and oceans in order to better understand the role that they have in governing the variability of the Earth's climate. Current research is now seeking to establish the probability and magnitude of future climate change, and to determine past climate change by looking at palaeo data records. Studies have also focused on both natural forcing functions and anthropogenic influences on climate change. These include work on processes originating in the Antarctic and the sensitivity of the global climate system to them, and work in the Arctic as an area of sensitivity in which marine processes are crucial to understanding short term (sub-decadal) impacts.

  The RAPID and COAPEC directed programmes, and programmes at BAS, CASIX, SAMS and NOCS are particularly relevant.

What is the role of the Atlantic's overturning circulation in regulating climate? What are the causes of, and changes in, the variability in the North Atlantic oscillation?

  In addition to the work undertaken through centre programmes (NOCS, SAMS) on the circulation in the Atlantic, key components of both the RAPID and COAPEC programmes have focused on the Atlantic overturning circulation. Examples of issues that have been examined are: the role of air-sea forcing, the role of sloping topography, the role of salinity, balancing of heat and freshwater budgets, heat transfer and storage, variation in these processes and their impact on the global climate. BAS work in the Antarctic has examined how the dense water masses in the Antarctic influence the global ocean circulation.

What are the physical, chemical, geological and biological consequences of climatic perturbations on the world's ice sheets?

  The primary objective of the AUI programme is to investigate the marine environment of floating ice shelves with a view to advancing the understanding of their role in the climate systems, and together with core programme work undertaken by BAS the knowledge base in this area has been greatly expanded.

What are the biological and geological feedbacks on the climate system in response to climate change? How will natural climate-erosion feedback be modified by climate change, and what will the impacts be?

  In order to provide greater understanding of the climate system, work is being undertaken from the microbial to ecosystem level. Modelling studies are being carried out in conjunction with this work towards determining the impacts of variations in the climate system as a result of climate change.

  The UK SOLAS directed programme, and programmes at MBA, PML and SAMS are particularly relevant.

What are the past-century trends in European and UK mean and extreme sea-levels? What are the causes of sea-level change and can we accurately predict the changes from a combination of climate and geodynamic models?

  Studies are being undertaken not only to evaluate past trends in mean and extreme sea level, but also to compare these measurements to climate and geodynamics models in order to establish how well they perform. Developmental research is being undertaken to improve the current techniques of sea level monitoring, which should provide greater understanding of sea level change. This type of work extends from the European to Antarctic climate, where work is being conducted to establish the history of ice sheets and subsequently use this information in ice-sheet simulation models.

  BAS, BGS and POL programmes are particularly relevant.

How strong is the link between climate change and natural hazards and disasters, such as storms, coastal erosion, floods, landslides and drought?

  Interdisciplinary work, from estuaries and coasts to the deep oceans, is being undertaken to examine how the different processes in the marine environment that contribute to climate control may be linked to natural hazards. This work includes topics such as sediment dynamics and coastal defence, and ocean-atmosphere interactions.

  Whilst submarine landslides and similar geological events can occur independently of climate change, it is possible that climate-change-related changes in sediment stability (eg related to gas hydrate release) could increase the probability of tsunami-generating events.[67]

  The COAPEC directed programme, and BGS and PML programmes are particularly relevant.

How will terrestrial and marine species adjust to climate and environmental change, especially within the fragmented land uses of Europe? How can conservation practices assist the process of adjustment?

  Underpinning research is being conducted in order to provide a greater understanding of marine ecology—towards establishing those factors that may limit and control population dynamics and distribution. From this base, work is now being undertaken to try and predict how marine species may be impacted by both natural and anthropogenic changes in their environmental conditions. The implications for ecosystem functioning are being considered.

  The Marine Productivity directed programme, and programmes at MBA, NOCS, SAMS and SMRU, and the AMT consortium, are particularly relevant.

What are the impacts of climate change on continental shelves, and what are the implications for coastal-zone management?

  Through direct measurements and modelling methods, changes in the continental shelves, as a result of climate change, are being investigated. Part of this work is focused on establishing how this may impact upon costal defences, which will be essential in determining the implications for coastal zone management. Ecological impacts of and habitat creation by sea defences have been investigated to inform environmentally sensitive design.

  BAS, BGS, MBA, PML, POL, and SAMS programmes are particularly relevant.

STRATEGIC PRIORITY 3:  SUSTAINABLE ECONOMIES

What are the environmental, economic and social impacts of renewable energy sources in terms of their complete generation cycles, including power source, infrastructure, and site impacts?

  Through collaborative work POL is seeking to develop models that can demonstrate the impacts of anthropogenic activities such as the establishment of offshore renewable energy operations. The SAMS artificial reef programme contributes to our understanding of artificial ecosystem creation and manipulation required for the foundations of offshore windfarms and tidal barrages. Work on the physics of tidal jets in fjords is being used to assess the potential of tidal barrages in sea loch systems.

What are the environmental risks of exploiting gas hydrates as an energy source? What is their role in large undersea slumps, which could result in dangerous tsunamis, as well as climate variability? What scope is there for under-sea carbon sequestration?

  Work is being carried out on gas hydrates towards assessing them as a hazard and potential energy source. Together with work on habitat mapping, and improvements in prediction (for exploration) and reservoir characterisation, the understanding of marine geohazards and their potential impacts are becoming better understood.

  The Ocean Margins LINK directed programme, BGS and NOCS programmes, and the new "Dynamics of gas hydrates" consortium are particularly relevant.

  Through BGS and PML, NERC is also assessing the appropriateness and potential impact on the marine environment of under-sea carbon sequestration.