NW Climate Science Digest

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

Snowmelt rate dictates streamflow

Barnhart, T. B., Molotch, N. P., Livneh, B., Harpold, A. A., Knowles, J. F., & Schneider, D. (2016). Snowmelt Rate Dictates Streamflow. Geophys. Res. Lett. Geophysical Research Letters. doi:10.1002/2016gl069690

A recent paper in Geophysical Research Letters presents a possible mechanism linking snowmelt rate to streamflow generation. The results of the study indicate that there is a strong correlation between snowmelt rate and baseflow efficiency, which supports the idea that greater snowmelt rates increases subsurface flow. As temperatures continue to increase this may lead to earlier, slower snowmelt, decreasing streamflow production.

Developing a representative snow monitoring network in a forested mountain watershed

Gleason, K. E., Nolin, A. W., & Roth, T. R. (2016). Developing a representative snow monitoring network in a forested mountain watershed. Hydrology and Earth System Sciences Discussions Hydrol. Earth Syst. Sci. Discuss., 1-26. doi:10.5194/hess-2016-317 

Current snow monitoring networks may not be representative of basin-scale distributions of snow water equivalent (SWE), especially in areas where forests and snowpacks are changing. To address this issue, researchers conducted a study to determine the key physiographic drivers of SWE; classify the landscape based on those physiographic drivers; and use that classification to identify a parsimonious set of monitoring sites in a forested watershed in the western Oregon Cascades mountain range. Once this was established, snow monitoring networks were put into place and usable data was collected over a five-year period. The monitoring network provides a valuable and detailed dataset of snow accumulation, snow ablation, and snowpack energy balance in forested and open sites from the rain-snow transition zone to upper seasonal snow zone in the western Oregon Cascades.

Flows of the Future—How Will Climate Change Affect Streamflows in the Pacific Northwest?

Grant, G., Safeeq, M., Staab, B., Lewis, S., Kramer, M., & Tague, C. (2016, July). Flows of the Future—How Will Climate Change Affect Streamflows in the Pacific Northwest? Science Findings, (187). Retrieved from http://www.fs.fed.us/pnw/sciencef/scifi187.pdf 

Scientists at the Pacific Northwest Research have created streamflow sensitivity maps that indicate how major watersheds are expected to respond to climate change. The research discusses several ways in which climate change can impact streamflow including flow volumes and the role precipitation plays in maintaining adequate water levels. The maps are intended for use by land managers in both Washington and Oregon to adapt specific management plans. 

Biodiversity/Species and Ecosystem Response

What a fruit fly’s body temperature could reveal about climate change

Macmillan, H. A., Knee, J. M., Dennis, A. B., Udaka, H., Marshall, K. E., Merritt, T. J., & Sinclair, B. J. (2016). Cold acclimation wholly reorganizes the Drosophila melanogaster transcriptome and metabolome. Sci. Rep. Scientific Reports, 6, 28999. doi:10.1038/srep28999 

According to an article published in Scientific Reports, an international study led by Canadian environmental physiologist Heath MacMillan has found that fruit flies adjust to a sudden drop in temperature by drastically changing their genes and metabolism. Researchers raised fruit flies from eggs through to their maggot stages at a room temperature of 21°C, and transferred them to a 6°C space once they were mature. The flies adjusted to the so-called “chill coma” by changing about a third of their 15,000 genes. The finding is important because understanding insects’ temperature tolerance is a crucial step in protecting and controlling insects worldwide, and could someday help scientists unravel the effects of climate change on insects.

Climate and Weather Reports and Services

Long-term Pacific climate cycle linked to expansion of Antarctic sea ice

Summarized by Hickey, H. (2016, July 5). Long-term Pacific climate cycle linked to expansion of Antarctic sea ice. http://www.washington.edu/news/2016/07/05/long-term-pacific-climate-cycl...

Meehl, G. A., Arblaster, J. M., Bitz, C. M., Chung, C. T., & Teng, H. (2016). Antarctic sea-ice expansion between 2000 and 2014 driven by tropical Pacific decadal climate variability. Nature Geoscience 9(8), 590-595. doi:10.1038/ngeo2751

According to a paper published this week in Nature Geoscience, the trend of increasing Antarctic sea ice can be mostly explained by a natural long- term climate fluctuation. The study sought to explain why Antarctic sea ice is expanding despite climate-related global warming. The authors offered evidence that the current negative phase of the Interdecadal Pacific Oscillation, which brings cooler-than-average sea surface temperatures in the tropical eastern Pacific, has created favorable conditions for additional Antarctic sea ice growth since 2000. The ultimate impact is a deepening of a low-pressure system off the coast of Antarctica known as the Amundsen Sea Low. Winds generated on the western flank of this system blow sea ice northward, away from Antarctica, helping to enlarge the extent of sea ice coverage.

There’s one place in the world that's getting colder instead of warmer

Summarized by Deaton, J. (2016, June 30). There's one place in the world that's getting colder instead of warmer. http://www.businessinsider.com/one-place-in-the-world-that-isnt-warming-...

Armour, K. C., Marshall, J., Scott, J. R., Donohoe, A., & Newsom, E. R. (2016). Southern Ocean warming delayed by circumpolar upwelling and equatorward transport. Nature Geoscience 9(7), 549-554. doi:10.1038/ngeo2731

According to an article published in Nature Geoscience, while Arctic sea ice has diminished, Antarctic sea ice has persisted and even grown. New research shows that as surface waters migrate northward, they are replaced by cooler waters from the depths of the ocean--waters that have not seen the light of day in hundreds or thousands of years. These ancient currents have been protected from rising temperatures. Cold Antarctic waters originate in the North Atlantic, the northernmost stop along an oceanic conveyor belt that extends the length of the planet. Arctic waters travel south along the bottom of the sea towards Antarctica. Once they hit Earth’s southern pole, they rise to the top and return north along the surface of the ocean, absorbing heat along the way. This system dampens warming in the Antarctic and exacerbates warming in the Arctic. While some may see this as good news for sea- level rise, the research shows that it makes little difference, as cool waters are responsible for preserving sea ice. What the research does show is that rising temperatures are far from uniform.

Coastal/Marine Ecosystems, Ocean Acidification, Sea Level Rise

Ocean acidification will make it hard for mussels to hang on

Johnson, L. (2016, July 06). Ocean acidification will make it hard for mussels to hang on experiments suggest; British Columbia, CBC News. Retrieved July 26, 2016, from http://www.cbc.ca/news/canada/british-columbia/ocean-acidification-will-...

According to a presentation by Emily Carrington, a professor at the University of Washington in Seattle, at the annual meeting of the Society of Experimental Biology, warmer ocean temperatures and rising ocean acidification levels pose a threat to mussels by weakening the threads they produce to bind themselves to their substrate. If those threads break — or fail to attach at all — the mussel will be tossed from the tidal zone it thrives in to deeper, calmer waters, with less food and more predators. Warmer water means the native mussel, Mytilus trossulus, produces fewer, weaker threads. More acidic water means the biological 'glue' — which needs higher pH--doesn't stick as well. Even though oceans are not yet so acidic that the mussels are unable to develop their “lifelines”, things are heading in that direction.

Climate Central launches a new online tool for exploring sea level rise and flood risks

Climate Central’s Program on Sea Level Rise launched a new interactive web tool this month. Their newly redesigned public sea level rise and coastal flood risk tool for the U.S. is called Surging Seas Risk Finder. The tool has several new features, including a streamlined user interface, downloadable figures, and a localized fact sheet. 

Ocean acidification alters the response of intertidal snails to a key sea star predator

Jellison, B. M., Ninokawa, A. T., Hill, T. M., Sanford, E., & Gaylord, B. (2016). Ocean acidification alters the response of intertidal snails to a key sea star predator. Proceedings of the Royal Society B: 283(1833), 20160890. doi:10.1098/rspb.2016.0890 

Researchers examined how ocean acidification alters the behavioral response of a prey species, the black turban snail (Tegula funebralis) to an iconic predator, the sea star (Pisaster ochraceus) within the rocky intertidal zone of the temperate eastern Pacific Ocean. Researchers assessed interactions between these species at 16 discrete levels of pH, quantifying the full functional response of Tegula under present and near-future ocean acidification conditions. They found that snails showed fewer anti-predator behaviors at low pH and spent less time in refuge locations. These results suggest that there is a strong potential for ocean acidification to create cascading community-level shifts within the ecosystem. 


Increasing western US forest wildfire activity: sensitivity to changes in the timing of spring

Westerling, A. L. (2016). Increasing western US forest wildfire activity: Sensitivity to changes in the timing of spring. Philosophical Transactions of the Royal Society B: Biological Sciences, 371(1696), 20150178. doi:10.1098/rstb.2015.0178 

Prior work shows western US forest wildfire activity increased abruptly in the mid-1980s. This study shows that the number of large forest fires and the areas burned within them have continued to increase in recent decades. Forests in the northern Rockies dominated early increases in wildfire activity, and still contributed 50% of the increase in large fires over the last decade. However, the percentage growth in wildfire activity in Pacific northwestern and southwestern forests has rapidly increased over the last two decades. Wildfire numbers and burned area have also increased in non-forested areas. This study shows that wildfire activity is strongly associated with warming and earlier spring snowmelt. Areas of forested lands with earlier spring snowmelt have been most greatly affected due to the loss of moisture.


Group clones California giant trees to combat climate change

Smith, S. (2016, July 20). AP News, The Columbus Dispatch. Retrieved July 26, 2016, from http://hosted2.ap.org/OHCOL/8ef5320729ce4298abefc1903704c7d5/Article_201... Giant Trees/id-7a84a9b1a99d4f0da814be775d919baa 

New growth samples are being taken from the tops of giant sequoia trees in California in an effort to combat climate change. The cloning expedition to Camp Nelson, a mountain community about 100 miles southeast of Fresno, was led by David Milarch, co-founder of Archangel Ancient Tree Archive. Relying on common sense that he says is being borne out by science, Milarch believes the size and robustness of the giant sequoias make them ideal for absorbing greenhouse gases that drive climate change on the planet. The collected samples are then grown beneath purplish fluorescent lights under humidity and temperatures designed to encourage rooting. Later this year, Archangel's team will come west to plant up to 1,000 sequoia and redwood saplings in a cool, damp region of Oregon where the trees will have the best chance to grow.

Observed forest sensitivity to climate implies large changes in 21st century North American forest growth

Charney, N. D., Babst, F., Poulter, B., Record, S., Trouet, V. M., Frank, D., . . . Evans, M. E. (2016). Observed forest sensitivity to climate implies large changes in 21st century North American forest growth. Ecology Letters Ecol Lett. doi:10.1111/ele.12650 

Researchers used a network of over two million tree ring observations from areas across North America to forecast climate impacts on future forest growth. By doing this, researchers are able to better understand the relationship between forest productivity and climatic stress and can help predict long-term trends in forest growth regionally. They found that climate change negatively impacted forest growth rates in the interior west and positively impacted forest growth along the western, southeastern and northeastern coasts. They also found that shifting climate sensitivities offset positive effects of warming on high-latitude forests, leaving no evidence for continued ‘boreal greening’, and that forests have to use water more efficiently in order to compensate with reduced growth rates. The authors emphasize the importance of locally adapted forest management to handle regional differences in growth responses to climate change.

Special issue of Western Forester on managing forests in the face of drought

Western Forester released a new issue on managing forests in the face of drought and changing climate. It includes an article about defining and monitoring drought in the Pacific northwest by Kathie Dello, a description of silvicultural strategies for reducing drought impacts by Matt Powers, and a discussion of future challenges by Timothy Link, Jessica Lundquist and Susan Dickerson-Lange.

Taking Action

Using Scientific Conferences to Engage the Public on Climate Change

Hicke, J. A., Abatzoglou, J. T., Daley-Laursen, S., Esler, J., & Parker, L. (2016). Using Scientific Conferences to Engage the Public on Climate Change. Bull. Amer. Meteor. Soc. Bulletin of the American Meteorological Society. doi:10.1175/bams-d-15-00304.1 

Scientists need to engage the public in meaningful conversations about climate change in order to change common misconceptions. New research shows that involving the public in discussions about climate change helps them better understand the science and how climate change will affect them at a local level. Authors of this paper report results of efforts made by planners of the 2015 Northwest Climate Conference in Coeur d'Alene, Idaho to reach local communities with climate information. They found that “local contacts with excellent connections to schools, civic organizations, local government, and interest groups, and a pool of motivated, enthusiastic conference attendees who were already traveling to the area were key to carrying out successful conversations with the public.”

Tribal and Indigenous Peoples Matters

Columbia River fishing plan could alter limits for salmon, steelhead

Press, T. A. (2016, July 10). Columbia River fishing plan could alter limits for salmon, steelhead. Retrieved July 26, 2016, from http://www.oregonlive.com/pacific-northwest-news/index.ssf/2016/07/colum...

Federal authorities are working on a plan to decide how much sport, commercial and tribal fishing for salmon and steelhead will be allowed in the Columbia River and its tributaries as part of a long-term agreement starting in 2018. One of their main determining factors is hatchery production level. The agencies, along with Idaho, Oregon, and Washington, as well as tribes from those states, will work together to create a 10-year agreement. The previous agreement took effect in 2008 and expires at the end of 2017. Courts have previously found that tribes are entitled to half of the harvestable return of salmon and steelhead. The new agreement will set production levels for hatcheries in the three states.