Co-Conveners:

Donald Boesch, University of Maryland

Virginia Burkett, United States Geological Survey

Rapporteurs:

Thomas Barnwell, Environmental Protection Agency

Eileen Shea, Center for the Application of Research on the Environment

Archivists:

Laurie Geller, National Research Council

Susanne Moser, Harvard University

The large and diverse group of individuals participating in this breakout session met first in plenary to hear five brief perspectives on various aspects of the effects of climate change on Coastal and Islands Regions intended to stimulate breakout group discussion. Michael Hamnett (University of Hawaii) provided the group with an overview of some of the current issues facing the Hawaii-Pacific region, current challenges and opportunities associated with climate variability and change, and critical information needs related to climate variability and change in the region. Jim O'Brien (Florida State University) then provided some perspectives on climate-related changes in tropical storm patterns and sea level rise. Rita Colwell provided the group with some thoughts on potential health-related impacts of climate variability and change, including issues related to changes in temporal and geographic patterns in infectious diseases and the impact of coastal storms and sea level rise on water supplies. Virginia Burkett provided the group with an overview of issues related to the importance and vulnerability of coastal wetland systems with an eye toward how climate-related changes might interact with other existing causes of wetlands loss and alteration. Don Boesch then provided some perspectives of how climate variability and change might alter vulnerabilities associated with two key current stresses: habitat loss and freshwater quantity and quality. A brief summary of the key points raised in these presentations is included as Attachment A to this synthesis report.

After general group discussion of issues raised by these panelists, the Coastal and Island Regions breakout session sub-divided into two smaller groups focused on 1) the human dimensions of the vulnerability of coastal regions to climate variability and change (chaired by Don Boesch); and 2) issues related to climate-related changes in environmental resources and processes (chaired by Virginia Burkett). This synthesis of those discussions is organized around: a) a summary of underlying themes; b) perspectives on the framing of climate-related issues in coastal regions (the focus of the human dimensions sub-group); and c) critical information needs (the focus of the environmental resources and processes sub-group).

Underlying Themes

Both plenary and smaller-group discussions among the participants identified a number of underlying themes important for the design of a National Global Change Assessment process which addresses issues of climate variability and change in coastal regions, including:

1. Natural and human systems in coastal regions are highly vulnerable to climate changes, in part because they are already subject to a number of stresses associated with natural variability in environmental conditions (including but not limited to climate) and with intense human activities (such as coastal land use and development).
2. To understand the consequences of climate change one must recognize the dynamic and adaptive nature of both natural and human systems in the coastal region. Natural and human systems in coastal regions already adapt to significant natural variability in climate (such as changes associated with El Niño). Demographic and technological changes in the coastal region are and will continue to be significant;
3. Consider both the effects of natural variations in climate and the interactions of natural variability with long-term climate changes.
4. Consider the consequences of episodic, extreme events (e.g. storms and floods) as well as long-term trends and changes.
5. The consequences of climate are highly interactive with other environmental and socio-economic stresses in coastal regions and should be viewed in the context of those other existing stresses. The Assessment should include considerations of how adaptation to current stresses may mitigate or may be exacerbated by the effects of climate variability and change.
6. It would be most useful to focus on greatest vulnerabilities (defined by one participant as a function of exposure, resistance and resilience) in the Assessment process.
7. Temporal and spatial scales are significant; the nature and importance of climate-related vulnerabilities is variable among regions and sectors.
8. Assessing the consequences of climate variability and change for coastal regions (and, most likely for all regions) should include consideration of intergenerational and social equity issues. For example, although wealthy beachfront landowners may be able to adapt to the effects of sea level rise and storms, impoverished communities occupying low-lying coastal regions may not be capable of adapting to or mitigating the consequences of climate change.
9. A successful Assessment should facilitate access to and use of information relevant to local, regional and national decision making. In particular, it should demonstrate near-term relevance of longer-term climate change. The Assessment should address scientific and technological challenges associated with a) providing appropriate regional detail, b) transforming scientific results into usable information, and c) developing coping strategies. It should also address the communications and education challenges of sustaining an interactive dialogue among interested parties.

Framing Issues

How best do we view issues of climate variability and change in order to provide useful and usable information to support local, regional and national decision making? To answer this question, the Assessment must seek to explain how changes in climate (weak or strong) interact with other factors to alter (potentially exacerbate) existing vulnerabilities in coastal regions. For these purposes, vulnerability was defined as a combination of "exposure, resistance and resilience." Assessing the consequences of climate variability and change should be set in the context of how changes in climate might affect current vulnerabilities to existing stresses, in particular:

1. Will current vulnerabilities change as a result of climate variability and change; if so, how?
2. What information is needed to understand and respond to these changes?
3. What coping strategies would be most effective in reducing vulnerability and/or enhancing capabilities to adapt to or mitigate the consequences of those changes?

It is important, therefore, to frame national assessment discussions of climate in the context of issues which individuals, government agencies, and public- and private-sector interests already perceive as environmental, social or economic stresses requiring attention, including: coastal erosion; storm damage; demographic and development pressures; wetlands and coral reefs (and other critical habitats); water quality and water supply; fish and shellfish; economic vitality and infrastructure; and public health.

Critical Information Needs

Critical information needs associated with an effective assessment of the consequences of climate variability and change for coastal are identified under four questions:

1. What information on meteorological changes would be most important?
   1. An extended record of past climate change on a regional basis for past 200 years should be assembled. We should build records of past climate from proxies (tree rings, river terraces, etc.) to characterize natural variability. Information on ecologically important variables (precipitation, soil moisture, runoff peaks, stream velocity, sea level) is particularly important.
   2. Information needed for improving the understanding of role of episodic events in ecosystem health. It is important to recognize that ecosystems are often dependent on variability, for example hurricanes recharge Florida aquifers.
   3. The magnitude and frequency of changes should be characterized. Ecosystems respond differently to long-term, gradual change than to abrupt episodic change.
   4. Meteorologists must strive to provide information relevant to ecologists. Often, appropriate information from models is not made available because meteorologists focus on summary information, while ecologists are interested in more details.
   5. Ecologists need better regional-scale projections, supported by better computing capabilities and validation of projections.
   6. Meteorologists should investigate ensemble forecasting techniques for regional projections of natural variability as a substitute for raw computing power. Consideration should be given to a "team approach" for developing consensus among climate modelers to provide information to those responsible for preparing assessments.

    

2. What information about environmental change would be most important?
   1. Ecosystem response to long-term change as well as episodic events should be characterized. Mangroves can adapt to slow sea level rise, for example.
   2. Make connections between climate change and ecosystems: Feedbacks between coastal ecosystems and climate must be considered and both direct and indirect impacts examined.
   3. Coastal and island ecosystems most valued by society should be identified and requirements for their conservation described.
   4. The U.S. Global Change Research Program should encourage greater U.S. participation in the Inter national Geosphere-Biosphere Program's Land-Ocean Interactions in the Coastal Zone (LOICZ) Program with the goal of placing coastal climate changes in functional and global contexts. In particular, it will be important to integrate U.S. work with international partners and develop capabilities to conduct assessments at comparable levels of confidence and detail.
   5. Information is needed on how the hydrologic cycle affects ecologically relevant processes such as nutrient loading to the coastal zone.
   6. There should be a focus on information on the vulnerability of coastal ecosystems to climate change and not just on descriptions of the change, itself.
   7. Opportunities for biological management should be identified Where are there "win-win" opportunities? Maintenance of migration corridors and encouraging habitat diversity are activities that reduce vulnerability to climate change, for example.

    

3. What information about socio-economic and human dimensions would be most important?
   1. There should be a recognition that population growth and distribution and changing land use dominate many coastal zones. Land use and change projections for the time horizon of the assessment years are required to truly assess relative impacts.
   2. Information is required on how other human-induced changes (e.g. land-use changes, nutrient loadings, wetland conversion, water use and flood control) increase vulnerability to climate change.
   3. Information is also needed on how human management and use of ecosystems and their resources affect vulnerability to climate change.
   4. Valuations of ecosystem services and aesthetics, as well as of conventional economic uses, are critical for conveying the impact of ecosystem change to policymakers.

    

4. What information about preparing for climate change and variability would be most important?
   1. We must understand how climate change is superimposed on other changes.
   2. Regional and local managers need guidance on what to do with the information provided by scientists. A communications strategy should be part of the assessment.
   3. Inventories of current research and data should be assembled to share with others.
   4. Care should be taken to include consideration of a variety of climate and global change-related impacts on coastal regions. For example, while sea level rise represents a tremendous and immediate threat to coastal regions, it will also be important for the Assessment to address other issues such as: the impacts of increased temperature on people, flora and fauna; the consequences of changes in UV-b radiation; human susceptibility to water-borne diseases; and soil moisture changes.

    

Finally, the consensus of the group is that coastal regions are highly vulnerable, in large part because of other components of human-caused change. Improving regional capabilities to understand and distinguish climate-related impacts on coastal ecosystems should be a high priority.

Final Recommendations

The group recommends a broad, interdisciplinary initiative for understanding and assessing coastal vulnerability and impacts. In this context, the group recommends a cross-agency planning effort to support: (1) synthesis and integration of data; (2) in-depth assessments of impacts on a sub-regional/local basis; and (3) more effective communication of research findings (including a specific recommendation that the U.S. Global Change Research Program consider a World Wide Web page with links to institutions that have technical information about climate change and impacts).

Don Boesch opened the discussion, introduced the speakers and laid out the agenda. He explained that this particular breakout group was different in that it is not looking at one contiguous region. Participants have to consider issues common to all the coastal regions. Four panelists then each gave brief presentations:

Michael Hamnett provided an overview of some of the current issues facing the Hawaii-Pacific region, current challenges and opportunities associated with climate variability and change, and critical information needs related to climate variability and change in the region.

Jim O'Brien talked about hurricane/El Niño correlation patterns, explaining that El Niño doesn't increase the number of hurricanes but it greatly alters their patterns. He noted that sea level rise is not currently accelerating, but Northern mid-latitude storms are getting stronger. Thus those living on coasts in Northern midlatitudes will face more storm damage.

Rita Colwell discussed several points related to public health: a) rising sea level may disrupt the public health infrastructure that currently helps us control infectious disease outbreak, thus we need to either shore up this infrastructure or be prepared for greater spread of disease; b) increasing temperatures may lead to a northward movement of tropical diseases; c) many infectious diseases exhibit a seasonal dependence because the bacteria and viruses causing them have seasonal life cycles just like other living things; and d) we need more sustainability built into our public health infrastructure.

Virginia Burkett explained that coastal wetlands are among the most vulnerable habitats, largely because they are already so threatened and there is so much new development in these regions; however, these ecosystems do undergo natural changes anyway. She noted that data indicate that sea level rise is increasing in some regions. This could have many possible impacts including: increased submergence of wetlands, increased salinity, more carbon enrichment, and changing regimes of plant competition.

Don Boesch pointed out two other important issues to consider: preservation of habitats and maintenance of water quality. While most of the U.S. is showing increasing precipitation, the few regions that are showing decreasing trends (CA, TX) are regions already very vulnerable to a lack of fresh water delivered to coastal ecosystems. Disruption of the global nitrogen cycle is happening even faster than the disruption of the global carbon cycle. This has a whole host of implications for ecosystems, such as eutrophication of coastal ecosystems. With more precipitation, there is greater flow in rivers (like the Mississippi) and thus increased flow of nitrogen into coastal zones. This leads to a greater hypoxic region in the Gulf of Mexico.

There was then general discussion of some of the issues raised among the group, including:

• the need to consider the consequences of natural variability, such as El Niño, and the interaction between natural variability and long-term climate change;
• the need to recognize and understand natural and human system changes in coastal regions that might be anticipated in the future, independent of climate change (an associated issue related to the need, therefore, to set climate change in the context of other existing stresses and clearly sort-out cause and effect issues);
• anticipated changes in tropical storm patterns in the Pacific as well as the Atlantic Oceans;
• the importance of looking at thresholds and abrupt changes, not just long-term trends; and
• the importance of looking at consequences for urban ecosystems in coastal regions, not just natural systems.