Climate Change: Impacts and Adaptation Strategies for Washington’s Marine Resources

Amelia Kolb is a second-year graduate student in the Marine and Estuarine Science Master’s Program at Western Washington University’s Shannon Point Marine Center. She studies predator-prey interactions in the outrageously complex world of marine planktonic microbes and wishes she had more spare time for messing about in boats. She lives in Oak Harbor with her husband and a very enthusiastic dog.

On April 8, Sue Blake of Washington State University (WSU) Whatcom County Extension welcomed about 120 people to an all-day Bellingham climate change adaptation symposium. The event, “Time to Act – Adapting to Climate Change in Whatcom County,” was designed to provide information about what impacts climate change will have on various areas of local concern, to address current and future challenges and to provide a forum for discussing how we can adapt to climate change. Blake emphasized that the point of the symposium was not to discuss whether climate change was occurring or why, but rather what to do about it.

“We don’t want the conference to be about placing blame,” she said. This goal is admirable in that it allows engagement with community members who may not agree that the cause of climate change is anthropogenic, but who understand that it is occurring and are concerned about how to adapt.

However, as keynote speaker Dr. Thomas Ackerman later alluded to, a hesitancy to acknowledge the causes of climate change precludes our ability to understand accurate predictions of the effects of climate change and therefore makes effective and timely adaptation impossible.

Sponsored by the City of Bellingham, the Nooksack Salmon Enhancement Association (NSEA), Sea Grant Washington, WSU Whatcom Extension and Western Washington University’s (WWU) Shannon Point Marine Center (SPMC), the symposium covered climate change impacts on a wide range of areas including water and forest resources, urban and rural infrastructure and agriculture. More than 15 scientists, educators and local agency and government representatives made presentations.

Attendees included community members, students, scientists and representatives from local government, businesses and non-profits. This article covers projected changes in Washington mainly as they relate to marine resources (see “For Additional Information” for further discussion).

Dr. Ackerman, Director of the Joint Institute for the Study of the Atmosphere and Ocean (JISAO) at the University of Washington (UW), studies global climate change and has done extensive climate modeling, particularly on the effects of clouds and aerosols on the earth’s radiation budget. He covered a short primer on the evidence for drastically rising CO2 levels due to human activity since the Industrial Revolution, including the classic Mauna Loa CO2 record, Antarctic ice core data and observed decreases in C14 to C12 ratios.

Basic physics asserts that increasing greenhouse gases such as CO2 must warm the atmosphere. However, predicting a specific temperature increase depends on many factors, including our own future emissions. As Dr. Ackerman stated, uncertainty about climate projections will never go away. He estimated that our uncertainty about the magnitude of warming over the next 100 years is about a factor of two; however, it is certain that there will be a general global warming trend. The degree to which different areas of the earth will warm, the effects of this warming on local climates and the effects of these changes on our natural resources and economies are all difficult predictions to make.

Despite the complexity of the system, regional climate models have been used to project expected changes to the Pacific Northwest under probable future greenhouse gas emission scenarios. In 2007, a bill was passed by the Washington State legislature mandating a complete assessment of the impacts of climate change on Washington. The Departments of Community, Trade and Economic Development and Ecology worked with the UW Climate Impacts Group, WSU and the Pacific Northwest National Laboratory to produce the Washington Climate Change Impacts Assessment (WACCIA). Much of the information about local climate change impacts presented at this conference was drawn from this assessment.

Washington has warmed by an average of 1.5 degrees F since 1920 and will continue to warm, likely at a higher rate in the 21st century than observed in the 20th century. The following impacts are average projected values from 20 different regional climate models that include two different emissions scenarios (B1 with lower future emissions and A1B with moderate future emissions, from the 2007 Intergovernmental Panel on Climate Change), all relative to the period 1970-1999. Average temperatures are projected to increase by 2 degrees F by the 2020s, 3.2 degrees F by the 2040s and 5.3 degrees F by the 2080s. Changes to annual precipitation are more uncertain, given the large natural yearly variability, and are small when averaged across all models (1 to 2 percent increase).

However, the timing of precipitation is projected to change, with wetter autumns and winters, drier summers and a decrease in winter snowpack. With more water falling as rain in the winter, and less falling as snow to later melt throughout the spring and summer, peak river flow from the Cascades is likely to occur during winter rather than early summer.

Dr. Ackerman pointed out several broad scale implications for these projected changes. Competition will increase in the summer for water that is used for power generation, irrigation and support of salmon spawning. There will be a lower demand for heating energy per person in winter, but a higher demand for cooling energy per person in summer. Sea level rise (due solely to water expansion from heating) will be dependent on location due to tectonic plate dynamics, but is projected to range from 1.3 feet at Neah Bay to 3.3 feet in the South Puget Sound region by 2100. Because water resists changes in temperature, sea level rise will remain slow in the first part of the century but will accelerate during the second half, necessitating a long-term view on coastal infrastructure adaptation.

Finally, Dr. Ackerman touched on ocean acidification due to the dissolution of CO2 in the global ocean as a topic of increasing recent concern for marine food web ecology and local shellfish farming. The presenters following Dr. Ackerman each discussed specific areas of concern resulting from these broader climate change impacts, and presentations addressing marine resources are summarized next.

The Pacific Northwest Coast is characterized by the upwelling of nutrient-rich, oxygen depleted water from ocean depths. This water passes through the Strait of Juan de Fuca and mixes with the well-lit surface waters of coastal embayments such as Bellingham Bay, fueling phytoplankton growth. Although this has historically been the base of a very productive marine food web supporting salmon, Dungeness crab and other commercially viable species, additional nutrient inputs from land combined with nutrients from upwelling may threaten the productivity and quality of these coastal waters. Dr. Jude Apple, a Marine Ecologist with SPMC explored this topic at the symposium.

Excessive nutrients causes extensive phytoplankton blooms, which predominantly die off and sink to the bottom rather than being passed to higher trophic levels. Bacterial decomposition of the sinking phytoplankton dramatically reduces oxygen concentrations in bottom waters. Although low dissolved oxygen is a natural feature of many coastal embayments and fjords of the Salish Sea, the combination of already low oxygen concentrations in upwelled water with anthropogenic nutrient-driven decreases in oxygen at depth conspires to produce critically low dissolved oxygen concentrations. These “hypoxic zones,” are now observed seasonally in places such as Hood Canal and Bellingham Bay.

With climate change, higher temperatures and a longer growing season will promote phytoplankton growth. The warming of surface waters will cause a more stable separation of lower density warm water at the surface and higher density cold water at depth (a phenomenon called stratification), inhibiting the mixing of the water column. This results in decreased replenishment of oxygen to hypoxic zones by inputs from high oxygen surface waters. Increased temperature will also increase the rates of bacterial decomposition, further depressing oxygen concentrations and creating hypoxic conditions that are more extensive and persist longer.

Hypoxia has been a major problem in other parts of the country, such as the Chesapeake Bay, resulting in reductions in economically important fish and shellfish populations. To avoid the same problems in the Salish Sea, Dr. Apple emphasized that we need to focus on what have the power to change rather than what we cannot control. Suggestions included watershed-scale nutrient management and development strategies to reduce nutrient inputs from land, preservation of important coastal habitat for juvenile fish and invertebrates and expanding research on the effects of climate change on local hypoxic zones and coastal water quality.

Taylor Shellfish Farms is the largest producer of farmed shellfish in the US. Since 2006, several shellfish farms in Washington have had major problems producing oyster seed through natural reproduction, with 60 to 80 percent reductions in larval production at some farms since 2008. Failed oyster reproduction has been linked to upwelled acidic water. Deep seawater upwelled along our coast has been circulating throughout the global ocean at depth for decades, containing CO2 from the last time it was at the ocean surface and gaining in CO2 concentrations as bacterial degradation of organic matter occurred at depth. Bill Dewey, Public Policy and Communication Director with Taylor Shellfish Farms spoke on this topic.

The process of gaseous CO2 dissolution in water alters water chemistry, causing pH to decrease and carbonate to be less available to organisms that build calcium carbonate shells. Oyster larvae appear to be particularly sensitive to this, especially the youngest stages that use an easily dissolved form of calcium carbonate in their very thin larval shells. With increasing atmospheric CO2 levels, the pH of the global ocean surface will continue to fall worldwide. With our location at the end of a long ocean circulation pathway, increasingly acidic water will upwell on our coast decades after it was last at the surface, which means that increased CO2 emissions in the future will be affecting calcifying marine organisms on the Pacific Northwest Coast many decades later.

Dewey discussed ongoing research efforts focused on mitigating this problem. One solution that Taylor Shellfish has used is closely monitoring water pH and weather, allowing management decisions prior to an upwelling event (driven by north winds) with water that will be too acidic for spawning and larval survival. Taylor Shellfish is also looking at a selective breeding program to produce a strain of oyster with larvae more resistant to low pH. Dewey ended his talk by suggesting that the oyster may be the “canary in the coalmine” of ocean acidification, heralding problems for many calcifying organisms in the future.

With warmer, wetter winters, we can expect a major shift in hydrology in Washington. Currently, many mid-elevation river basins in the Cascades (including the Nooksack) show small peaks in flow in the winter with major peaks in flow occurring with spring and summer snow melt. These rivers will become more rain dominated in the future, with peak flow occurring in fall and winter due to increased rain and reduced snowpack. Ingrid Tohver, Research Scientist with the Climate Impacts Group at the University of Washington spoke on this topic.

Models predict increased winter flooding in rivers such as the Skagit and Nooksack. Flooding and increased flow in the winter will reduce survival of salmon eggs and alevin stages due to scouring. Increasing summer stream temperatures and longer duration of the summer low flow season will affect juvenile and smolt salmon. Thermal stress and barriers to migration will increase, as will the prevalence of disease vectors that proliferate at higher temperatures. Additionally, sea level rise will reduce marsh areas important to migrating salmon and their food sources.

Tohver offered few adaptation strategies, but NSEA recommends ensuring maintenance of high genetic diversity in salmon populations and is active in restoration efforts of stream habitat, which will be increasingly important with climate change impacts.

Despite attempts to focus attention on possible adaptations to climate change, much of the symposium content was on projections of climate change impacts on specific areas. Suggested adaptations in each area remain nebulous. Because we are only recently able to project what will happen under future climate conditions regionally, it is unsurprising that we do not yet have all the answers. However, this symposium was one very positive step forward in that the organizers encouraged presenters to outline real opportunities for adaptation, a topic that has not had enough attention in public forums. Presenters communicated an important message to concerned community members in attendance: we already have some options for dealing with the impacts of climate change in Whatcom County, and the time to act is now.

It is important for future adaptation discussions to emphasize the consensus causes of climate change that are accepted by the scientific community. Although sadly many deniers of anthropogenic climate change have made up their minds about what to believe, accepting their point of view does little to further progress on climate change adaptation measures. The degree to which warming will occur, the magnitude of sea level rise, and the changes to local weather patterns are predicted based on climate science and under different potential greenhouse gas emission scenarios. Without an understanding of what the predictions are and how they are made, the public cannot make educated choices about changing personal lifestyle habits and prioritizing spending on adaptation to climate change.

Dr. Rebekah Green gave a short presentation on her work as the Associate Director of the Resilience Institute at WWU, which promotes education and preparedness for reducing community vulnerability to natural hazards. She made an important point about the resistance of some people to the idea of climate change. Apathy about and even vehement disbelief in climate change often arises from a feeling of helplessness. Dr. Green highlighted that our most important strategy is to make sure affected people perceive that we have the resources to overcome threats from climate change. Only by giving people the power to adapt can we hope for real resilience to climate change in Washington State. §