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Overview

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Issue

Coastal and marine ecosystems are intimately linked to climate, Thus, climate change will augment the problems already occurring in these vulnerable ecosystems due to increasing coastal populations, habitat loss, nutrient pollution and invasive species. Climate induced environmental changes expected to have the greatest effect on estuarine and marine ecosystems include:

  • Temperature changes will alter ecological processes and species interactions. The oceans distribute heat globally, and atmospheric and ocean processes work together to control both pelagic and coastal ocean temperatures.
  • Increase in frequency of extreme ocean warming events. Coral reefs have experienced unprecedented bleaching.
  • Projected changes in marine environment have important implications for fisheries resources and marine populations.
  • Changes in precipitation and run-off may increase the risk of flooding or drought. The delivery of nutrients, sediment and contaminants is closely linked to freshwater run-off.
  • Sea levels have already risen 10-25 cm over the last century. Global warming will accelerate these rates with a projected rise for 50 cm by 2100
  • Vulnerability of barrier islands to sea level rise and development that hinders natural migration.
  • Alteration of the patterns of wind and water circulation in the ocean. Increased temperature or decreased salinity could trigger changes in thermohaline circulation.
  • Sea ice over large areas of the Artic basin has thinned one to two meters, losing 40% of its total thickness since 1960. All climate models project large continued losses with enormous consequences for Artic populations and ecosystems.

Climate change has a profound impact on coastal and marine environments. Critical ecosystems such as wetlands, estuaries, and coral reefs are particularly vulnerable.

Coastal decision makers need scientific information in order to appropriately manage coastal ecosystems impacted by climate change.

Approach

CSCOR supports interdisciplinary, multi-year research programs investigating how oceanic and coastal ecosystems respond to climate variability and change. The long-term climate efforts of NOAA are designed to develop a predictive understanding of variability and change in the global climate system, and to advance the application of this information in climate-sensitive sectors through a suite of process research, observations and modeling, and application and assessment activities. CSCOR's climate change research focuses on sea level rise and fisheries.

Coastal subsidence already plays a major role in regional sea-level change, and accelerated global sea-level rise is expected to increase impacts in those regions where subsidence and erosion problems already exist. The vulnerability of a coastal area varies according to the physical attributes of the shoreline and the amount of development. Low lying developed areas in the mid- Atlantic, Southeast, and Gulf Coast are especially at risk. The major physical impacts include erosion of beaches, flooding and loss of coastal wetlands, and salinity in coastal aquifers and estuarine systems. Additionally, a possible increase in intensity and frequency of storms may jeopardize economic and ecological services. Damages and economic losses could be reduced if decision makers understand the potential impacts of sea level rise and use this information for planning. CSCOR has initiated a new program, the Ecological Effects of Sea Level Rise (EESLR). The Pilot Project, currently underway in the Pamlico Sound area of North Carolina, teams University researchers with NOAA scientists. Specialist in biology, geomorphology and coastal modeling are joining forces to integrate storm surge models with ecological models for more precise predictions of how future sea level will affect coastal wetlands, submerged aquatic vegetation, sub tidal habitat and oyster reefs.

Climate change is also likely to substantially alter the distribution and abundance of major fish stocks and have important implications for marine populations and ecosystems. As temperatures change, species' geographic distributions will change. Species that are unable to migrate or compete with other species for resources may face local or global extinction. In addition, climate change likely will alter patterns of wind and water circulation in the ocean environment. Such changes may influence upwelling and down-welling, thus changing the availability of essential nutrients and oxygen to marine organisms. CSCOR partners with the National Science Foundation to support the Global Ocean Ecosystems Dynamics program (GLOBEC), which addresses the question of how global climate change may affect the abundance and production of animals in the sea.

Management & Policy Implications

With 70% of the earth's surface covered by ocean and the majority of the world's populations living near the coast, proper management of our coastal resources is vitally important. Ocean and coastal ecosystems are comprised of diverse habitats that provide a wide variety of goods and services including food, transportation corridors, and food. Failure to proactively plan for and respond to climate change impacts will have ecological as well as economic implications. Loss or damage of important coastal ecosystems such as wetlands due to sea level rise will decrease fish and shellfish stocks, increase flooding and increase pollution. CSCOR's program of addressing major coastal issues, including climate change, enhances the Nation's capability to properly manage our precious coastal resources. CSCOR's goal is to provide managers with the scientific knowledge and tools, including ecological models, to prepare for climate change impacts, with more certainty in scale, timing and local detail.

Accomplishments

GLOBEC is a component of the US Global Change Research Program leading to understanding and better management of major fish stocks. GLOBEC results have been used by fishery managers in debating closed areas on Georges Bank in the Northwest Atlantic Ocean. Recent discoveries in the Northeast Pacific ocean show the importance of oceanic variability in influencing zooplankton species distributions, salmon growth and survival, and episodic events such as coastal hypoxia.

EESLR is a new program. Initiated in 2003, our partners within NOAA have developed a is a hydrodynamic tide model of Pamlico, Albemarle, Core, and Bogue Sounds. The models also adjacent estuarine and coastal waters and a high-resolution, topographic/bathymetric digital elevation model (DEM) which integrates recent airborne LIDAR (Light Detecting and Ranging) topographic data and bathymetric data. A hydrodynamic coastal flooding model has been developed which integrates the DEM and the tide model http://nauticalcharts.noaa.gov/csdl/welcome.html. In addition, CSCOR has competitively funded three research proposals that will integrate ecological models with the flooding model. Completion of the North Carolina project is projected in 2008.