NW Climate Science Digest

Aquatic Resources, Stream Flow, Hydrology in the Western U.S.

Western Water Report and Basin-Specific Manager Tool Released by the DOI

Reclamation (Bureau of Reclamation). 2016. SECURE Water Act Section 9503(c) – Reclamation Climate Change and Water. Prepared for United States Congress. Denver, CO: Bureau of Reclamation, Policy and Administration.

Under the requirements of the SECURE Water Act of 2009, the Department of the Interior’s Bureau of Reclamation has released a report characterizing climate-change induced projected effects for river basins in the Western United States. The Bureau of Reclamation, the largest provider of both water and hydroelectric power for the nation, worked with state and local partners to categorize the risks specific to each basin and produce a publically available online tool that visualizes these basin-specific impacts as well as potential adaptation options. Concerning the Northwest United States, the report discusses potential risks to the Columbia and Missouri River Basins, as well as the Klamath and Truckee River Basins. The report described the Columbia and Missouri basins as potentially exhibiting a precipitation shift from snow to rain. This shift indicates more runoff in the wintertime than the summertime due to less snow melt. Consequences of this climate-change induced impact will be reduced irrigation supply and hydroelectric power, and increased wintertime flood control challenges. The Klamath and Truckee basins were projected to exhibit increased stress on fisheries, salmon habitat loss, increased water and hydropower demand, and higher vulnerability to invasive species infestation. For more information, or to visit the online tool, go to: http://www.usbr.gov/climate/secure/

Shifts from Snow to Rain Precipitation Regimes and their Impact on Western Juniper

Niemeyer, R. J., Link, T. E., Seyfried, M. S., & Flerchinger, G. N. (2016). Surface water input from snowmelt and rain throughfall in western juniper: Potential impacts of climate change and shifts in semi‐arid vegetation.Hydrological Processes.

A new study, led by former NW CSC Graduate Fellow Ryan Niemeyer, looks at the impacts of shifting precipitation regimes due to climate change on western juniper. Specifically, it looks at impacts on surface water input due to changes in throughfall, meaning the amount of snow that is not blocked from the land-surface due to interception by trees. In addition to juniper, they also examined impacts on mountain big sagebrush and low sagebrush plant communities. The authors used a simultaneous heat and water model to simulate energy and heat fluxes and found that juniper reduced the amount of surface water input relative to sagebrush. Warming temperatures had a relatively minimal impact in terms of reducing surface water input for juniper and sagebrush. Their results are important given potential vegetation shifts due to climate change and the need to understand how shifting precipitation regimes will impact surface water input.

Arid Ecosystems

Implications of Drought for Dryland Ecosystems

Hoover, D., Duniway, L., & Belnap, M. 2015. Pulse-drought atop press-drought: Unexpected plant responses and implications for dryland ecosystems. Oecologia, 179(4), 1211-1221.

In this study, USGS scientist David Hoover and colleagues performed a 4-year study researching the effects of drought on plant functional types in order to understand how changes to precipitation could impact ecosystems. The authors examined four dominant, native plant functional types (C3 grasses, C4 grasses, C3 shrubs, and C4 shrubs) across a 4500 km^2 region of the Colorado Plateau. Over the 4-year study, a press-drought (long-term, chronic drought) was experimentally induced and a pulse-drought (short-term, intense drought) naturally occurred, giving the study a chance to examine the additive effect of both types of drought on an ecosystem. The authors found that C3 grasses were the most sensitive functional group to drought and C3 shrubs were the most resistant. The occurrence of both press- and pulse-droughts caused higher-than-expected mortality of C3 grasses. In addition, the study examined the interaction between soils and drought, however found that soil variety played no interaction with drought treatments, a result contrary to the authors’ prediction.

Biodiversity/Species and Ecosystem Response

Effects of climate, habitat and Barred Owls on demography of Northern Spotted Owls

Dugger, C. et al. 2016. The effects of habitat, climate, and Barred Owls on long-term demography of Northern Spotted Owls. Condor, 188 (1).

This reports presents results from field data collected during 1985–2013 to evaluate population processes of Northern Spotted Owls across its range in Washington, Oregon, and northern California. The authors estimated factors relating to survival and reproductive success, and investigated relationships between these parameters and the amount of suitable habitat, various climatic variables, and competition with Barred Owls. Estimated mean annual rates of population decline varied from 1.2% to 8.4% among study sites, with a weighted mean range-wide decline of 3.8%. Climate covariates were important in most models of spotted owl fecundity and survival, but there was little consistency among areas regarding the relative importance of specific climate covariates for survival. In contrast, meta-analysis results suggested that Spotted Owl survival was higher across all study areas when the Pacific Decadal Oscillation (PDO) was in a warming phase and the Southern Oscillation Index (SOI) was negative, with a strongly negative SOI indicative of El Niño events. The authors conclude that Northern Spotted Owl populations are declining throughout their range, and that rates of decline are accelerating in many areas. They posit that Barred Owl densities may now be high enough that the persistence of Northern Spotted Owls may be in question without additional management intervention.

Slow Climate Velocities on Mountain Streams Diminishes Climate-related Effects on Cold-water Species

Isaak, D. J., Young, M. K., Luce, C. H., Hostetler, S. W., Wenger, S. J., Peterson, E. E., Nagel, D. E. (2016). Slow climate velocities of mountain streams portend their role as refugia for cold-water biodiversity. Proceedings of the National Academy of Sciences. http://doi.org/10.1073/pnas.1522429113

Daniel Isaak and colleagues from the Rocky Mountain Research Station recently published a study examining the current predictions of short-term montane species loss due to large increases in stream temperature. The team of scientists used large databases of water temperature in order to diminish the effects of influential variables such as inaccuracy in smaller datasets and surrogate factors like elevation and air temperature. The study found a less dramatic shift in temperature for mountain streams suggesting a smaller threat to cold-water biodiversity. The authors concluded that mountains streams, due to local topographic controls on temperature, could in fact become important refugia for such species.

Biodiversity Critical to Maintaining Healthy Ecosystems

Grace, J. B., Anderson, T. M., Seabloom, E. W., Borer, E. T., Adler, P. B., Harpole, W. S., Smith, M. D. (2016). Integrative modelling reveals mechanisms linking productivity and plant species richness. Nature, 529(7586), 390–393. Retrieved from http://dx.doi.org/10.1038/nature16524

Researchers from the USGS recently published a new study that assessed the link between species richness and ecosystem productivity. Using a new integrative model and data from over 1,000 different grasslands around the world, the scientists were able to detect underlying trends that clearly linked productivity to species richness, something that bivariate models could not do. The authors concluded their study by emphasizing the importance of using integrative models to advance our understanding of the mechanisms driving ecosystem productivity. Many processes were identified using the integrative model that contradicted present understanding of ecosystem productivity. The significance of the effects of richness on productivity, the persistence of competition in ecosystems regardless of productivity, and the effects of macroecolocical gradients on local richness were among the mechanisms made visible through the use of this new model.

Climate and Weather Reports and Services

Regional Climate Change and National Responsibilities

Hansen, J., & Sato, M. 2016. Regional climate change and national responsibilities. Environmental Research Letters, 11(3), 034009. doi:10.1088/1748-9326/11/3/034009

James Hansen and Makiko Sato from the Earth Institute at Columbia University have released a report updating the effects of global warming in the Northern Hemisphere. Regional temperature data from 1951-1980 created a 50-year bell curve indicating average temperatures and anomalously cold and warm temperature for various regions of the world. Using these regional bell curves as baselines, Hansen and Sato compared them to bell curves of the same regions from 2005-2015 and calculated the difference in standard deviation. The average modern bell curve for the entire Northern Hemisphere is over one standard deviation warmer than the baseline bell curve. Hansen and Sato then examined bell curves of specific regions within the Northern Hemisphere, including the U.S., Europe, China, India, Middle East, Northern Africa, Central Africa, and SE Asia. The U.S. exhibited the smallest bell curve shift of approximately one standard deviation warmer in summer and 0.5 standard deviation warmer in winter, whereas the Middle East experienced the largest bell curve shift with a 2.4 standard deviation shift in summer and <1 standard deviation shift in winter. Tropical regions, such as central Africa and SE Asia exhibited bell curve shifts of approximately 2 standard deviations or more all year round. The authors concluded that warming the earth 2 C relative to pre-industrial temperatures will cause more extreme bell curve shifts than already observed. In addition, Hansen and Sato emphasized the responsibility of the developed world to recognize its role in reducing emissions and stressed the need to include societal costs in the price of fossil fuels.

Clear Evidence Found Between Climate Change and Heat Waves

A new report produced by the National Academies of Sciences, Engineering and Medicine, examined the latest understanding of “event attribution,” or scientists’ ability to attribute extreme climatic events to climate change. It is more difficult to characterize an individual weather event than a global trend, however the science surrounding such characterization has rapidly evolved in recent years. This report concluded that it is now possible for scientists to quantitatively state the extent to which climate change has influenced the magnitude and frequency of some classes of extreme events. The most apparent classes of events that scientists can associate with climate change are the ones directly related to temperature. Therefore, scientists have the highest understanding of the influence of climate change on heat waves and extreme cold events, followed by drought and extreme precipitation, but the lowest understanding of event classes such as wildfires, cyclones, or severe convective storms.

Coastal/Marine Ecosystems, Ocean Acidification, Sea Level Rise

Numerous Genetic Differences Found Between Wild and Farm Salmon

Mark R. Christie, Melanie L. Marine, Samuel E. Fox, Rod A. French, Michael S. Blouin. 2016. A single generation of domestication heritably alters the expression of hundreds of genes. Nature Communications. 7: 10676 DOI: 10.1038/ncomms10676

The genetic processes by which domestication of plants and animals occurs is largely unknown. In order to better understand these underlying mechanisms, a new study from Oregon State University compared the genome of wild salmon and first-generation farm salmon living in the same habitat. Scientist, Mark Christie and his colleagues collected wild-born and first generation hatchery steelhead trout from the Hood River, Oregon and performed a series of crosses. The scientists then measured differential gene expression between wild offspring (wild x wild) and first-generation hatchery offspring (hatchery x hatchery). The results showed 723 genes that were differentially expressed between the two groups. The genetic pathways of these differentially expressed genes were mainly for wound repair, immunity, and metabolism, all traits that would help fish adapt to a more crowded hatchery environment. The study also examined reciprocal crosses (hatchery x wild, wild x hatchery) to rule out the possibility that maternal effects or natural sampling noise were not the cause of the difference in gene expression. The study suggests that the earliest stages of domestication stimulate massive, heritable change to gene expression.

Millions Projected to be at Risk from Sea Level Rise in the U.S.

Hauer, M. E., Evans, J. M., & Mishra, D. R. (2016). Millions projected to be at risk from sea-level rise in the continental United States. Nature Clim. Change, advance online publication. Retrieved from http://dx.doi.org/10.1038/nclimate2961

In this study, scientist Mathew Hauer from the University of Georgia and colleagues attempt to address two key questions regarding sea level rise: 1) how many people are at risk from sea level rise, and 2) what areas in the US are projected to experience the greatest amount of population exposure to sea level rise? To answer these questions, they draw on the NOAA sea level rise data sets for 22 coastal states, including the District of Columbia. Two scenarios are studied; one scenario with 1.9 m of sea level rise and the second with 1.8 m of sea level rise. For the 1.8 m scenario, they find that 13 million people in the US are at risk of being affected. This includes 11, 178 people in Washington and 4, 374 in Oregon, and for higher sea level rise scenario, 11, 178 in Washington and 8, 985 in Oregon. The authors suggest that if measures are not enacted that would mitigate sea level rise, large population migrations could result as a consequence of sea level rise by the end of the twenty-first century.


Predicting Large Wildfires Across the West by Modeling Seasonal Variation in Soil Water

Waring, R.H. and Coops, N.C. 2016. Predicting large wildfires across western North America by modeling seasonal variation in soil water balance. Climatic Change, 135 (2).

This paper presents an approach to help identify forested areas where management efforts to reduce fire hazards might prove most beneficial. The authors constructed a decision tree model to establish general relationships among evaporation, transpiration and tree flammability. To test their decision tree model they used NASA imaging data to map large fires between 2000-2009 and analyzed seasonal variability in soil water for 2001, 2004 and 2007. They found that, for the three years selected, their decision model tree predicted where forest fires more than a kilometer occurred and did not occur with an average accuracy of 69%. The decision tree identified four seasonal combinations, most of which included exhaustion of available soil water, during the summer as critical- two combinations involving conditions the previous spring or fall accounted for 86% of the predicted fires.

Climate Change Refugia, Fire Ecology and Management

Wilkin, K.M., D.D. Ackerly and S.L. Stephens. 2016. Climate Change Refugia, Fire Ecology and Management. Forests, 77(7).

Refugia are habitats that buffer climate changes and allow species to persist in—and to potentially expand under—changing environmental conditions. This paper suggests that cold-air pools (areas with lower temperatures and higher moisture) act as an important type of small-scale refugia, having fewer fires and fires of lower severity. Active management, such as restoration and fuels treatments for climate change adaptation, may be required to maintain these distinctive and potentially important refugia. Interestingly while overall temperatures are increasing the weather patterns that cause cool-air pooling at the landscape scale are increasing, at least in the Sierra Nevadas, so the frequency and duration of cold-air pools may actually increase with climate change.


Landscape Pattern Analysis Reveals Global Loss of Interior Forest

Riitters, Kurt; Wickham, James; Costanza, Jennifer K.; Vogt, Peter. 2015. A global evaluation of forest interior area dynamics using tree cover data from 2000 to 2012. Requesting Publication

Researchers from the U.S. Forest Service analyzed Landsat data of global tree coverage from 2000 to 2012. The authors found that between 2000 and 2012, there was a net loss of 1.71 million km^2 of global forest coverage. While this is a large area, the researchers were more concerned about the amount of interior forest loss due to forest fragmentation because interior forest loss would increase the level ecological risk. Using the Landsat data and comparing locations of forest interior change, the authors calculated that there has been a net loss of 3.76 million km^2 of interior forest area. The authors concluded by stressing the importance of understanding interior changes to forests as it is more indicative of forest vulnerability.

Carbon Stocks and Accumulation Rates in Pacific Northwest Forests

Gray, AN, TR Whittier, ME Harmon. 2016. Carbon stocks and accumulation rates in Pacific Northwest forests: role of stand age, plant community, and productivity. Ecosphere, 7(1).

Forest ecosystems remove significant amounts of carbon from the atmosphere. The rates at which they do this and the overall quantity of carbon they store depend on abiotic resource availability and biotic interactions during forest succession. This study examined measured change in live and dead woody carbon pools on Pacific Northwest National Forest lands to determine how the balance of tree growth, mortality, and dead wood decomposition varied by stand age, plant community type, and site productivity; and to compare the contribution of different tree sizes to carbon accumulation.  The authors found that large trees accumulated carbon at a faster rate than small trees on an individual basis, but their contribution to carbon accumulation rates was smaller on an area basis, and their importance relative to small trees declined in older stands compared to younger stands. In contrast to recent syntheses, these results suggest that old-growth and large trees are important carbon stocks, but they play a minor role in additional carbon accumulation.

New Lidar Technology Used to Produce 3-D Mapping of Earth’s Forests

In this news report, NASA has announced it will be launching GEDI, a new Earth-observation system that uses Lidar to create 3-D maps of the Earth’s forests. GEDI will map and measure the volume of the world’s forests, and scientists hope to combine this visual dataset with knowledge of how carbon storage varies with wood in order to develop a more accurate conceptualization of how much carbon is stored in the Earth’s forests. The long-term goal of the GEDI project is to establish a forest baseline, or reference point, that can be used to measure changes over time, as well as a tool for addressing and managing land use and habitat diversity.

A Climate Adaptation Strategy for Conservation and Management of Yellow-Cedar in Alaska

Hennon, Paul E.; McKenzie, Carol M.; D'Amore, David V.; Wittwer, Dustin T.; Mulvey, Robin L.; Lamb, Melinda S.; Biles, Frances E.; Cronn, Rich C. 2016. A climate adaptation strategy for conservation and management of yellowcedar in Alaska. Gen. Tech. Rep. PNW-GTR-917. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 382 p.

This report was produced as an effort to synthesize the current conservation science and vulnerability of the yellow-cedar in Alaska. Written in collaboration with Alaska Region land managers, State and Private Forestry forest health professionals, and Pacific Northwest Research Station scientists, the report proposes conservation and management strategies that would address observed vulnerabilities. The report begins with a section on the ecological, historical, and economic value of the yellow-cedar, then discusses the reasoning behind massive population declines in the species. The last two sections discuss options for land management and conservation that would protect yellow-cedar forests, as well as future risks to the species based on distribution projections from risk models.

Land Use

Economic Underpinnings of Higher-Yield Farming

B. Phalan, R. E. Green, L. V. Dicks, G. Dotta, C. Feniuk, A. Lamb, B. B. N. Strassburg, D. R. Williams, E. K. H. J. z. Ermgassen, A. Balmford. How can higher-yield farming help to spare nature? Science, 2016; 351 (6272): 450 DOI: 10.1126/science.aad0055

In this article, recently published in Science, conservationists examined the economic realities behind one method of climate change mitigation: saving wild land from expanding agriculture by increasing yield in current agricultural spaces. This technique has been gaining popularity since more research has shown its viability for saving biodiversity in wild spaces. Because more and more policymakers are looking at this technique seriously, the authors wrote this article to forewarn policymakers of the likely consequences of implementing this new technique without defined parameters. Developing a policy that maximizes food production on current farmland could cause prices to drop and demand to increase, or higher yields may raise profits, either way inspiring farmers to expand their farmland. Therefore, the authors recommend a series of “land-sparing mechanisms” that intertwine yield increases with habitat protection so that wild spaces cannot be undermined.

Land Use and Land Cover Policies that are Climate Relevant

Mahmood, R., Pielke Sr, R. A., & McAlpine, C. A. (2015). Climate Relevant Land-Use and Land-Cover Change Policies. Bulletin of the American Meteorological Society

In this recently published paper, climate scientists develop and present several recommendations for the policies shaping land-use and land-cover management strategies. As more research reveals the significant role that land-use and land-cover have at every scale within the climate system, land management policies have kept a lack of representation of this research. The authors of this report proposed four recommendations: translating international protocols, such as the United Nations Framework Convention on Climate Change (UNFCCC), into national policies, bringing international protocols up-to-date on land-use and land-cover science in order to posit current research into policy, furthering research and data collection related to land management, and incorporating land-use and land-cover research into the UNFCCC program Reducing Emissions from Deforestation and Forest Degradation+ (REDD+).

Special Reports / Announcements

Scientists Warn of Potentially Perilous Climate Shift in Decades Rather than Centuries

Hansen, J., Sato, M., Hearty, P., Ruedy, R., Kelley, M., Masson-Delmotte, V., Russell, G., Tselioudis, G., Cao, J., Rignot, E. and Velicogna, I., 2016. Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2° C global warming could be dangerous. Atmospheric Chemistry and Physics, 16(6), pp.3761-3812.

A new study, led by renowned climate scientist James Hansen, claims that current burning of fossil fuels will cause an abrupt climate shift in a matter of decades rather than centuries. The authors argue that an increased influx of freshwater into the oceans will set off a feedback loop that will result in large parts of the Greenland and Antarctic ice sheets melting. However, the paper is not without controversy. In fact, last year, a draft version was published, and it sparked a major controversy among climate scientists. Some climate scientists argue that the standard of proof in Hansen’s study was not sufficiently high.

Taking Action

President’s Budget Includes Largest-Ever Investment in Puget Sound

“On Feb. 9, the President released his proposed budget, which includes an investment of more than $30 million for Puget Sound recovery and cleanup – $2 million more than last year’s allocation. The budget also allots $65 million to the Pacific Coastal Salmon Recovery Fund. These investments, if they go forward, would supplement state and local efforts to implement the Puget Sound Action Agenda, the region’s shared roadmap for restoring and protecting Puget Sound. Read more about the President’s budget proposal

Tribal and Indigenous Peoples Matters

Bureau of Indian Affairs Announces Tribal Climate Resilience Program Funding Opportunity

The Department of the Interior (DOI), Bureau of Indian Affairs (BIA) Tribal Climate Resilience Program (TCRP) has announced the FY16 Climate Funding Opportunity to support tribal projects addressing climate change adaptation (planning, workshops, and travel support); ocean and coastal management planning (and travel support); capacity building, and youth training (research, management, or youth engagement). In Fiscal Year 2016, a new category, capacity building, has been created to support tribes that have limited technical or staffing capacity to identify how the tribe or tribal organization can start addressing climate change adaptation. Deadline for proposals is May 23, 2016. More details can be found here.

‘Disastrous’ Coho Returns Threaten Western Washington Tribes

A recent news article discusses the impacts of low salmon returns for the western Washington tribal fishing nations. The warmer water experienced along the Northwest coast from “the Blob” and El Nino creates a less nutrient-rich marine environment and hurts the diet of both wild and hatchery fish. Consequently, the Northwest coast has experienced diminished salmon returns which has impacted fishing nations on an economic and cultural level. The Northwest Indian Fisheries Commission is concerned that the 2016 coho returns may be well below the quantity required to produce the next generation of salmon, and is therefore considering a “zero option,” which would mean closing all salmon fisheries in state waters. The Pacific Fishery Management Council is currently reviewing strategies that have been proposed as alternatives to the zero option. A decision for the 2016 season is expected by mid April.