By Adrienne Marshall

Late May in the Sierra Nevadas in 2015, a low snowpack year that enabled spring recreation in the high country. Photo: Darren Bagnall.

As an environmental scientist, I’ve done plenty of hiking in the western U.S., always with a map, water bottle and list of water sources. In dry areas it’s always smart to ration water until you get to a new source. Sometimes a stream has dried up for the season, or a pond is too scummy to drink from, so your supply has to stretch further than planned. On one memorable hike, I found that a water source was dry. The next one, three miles later, was dry too. And the one after that had a dead bear carcass in it. While one dry water source was tolerable, several in a row created a serious problem.

Something similar is happening to snow resources in the western United States. Scientists have long known that the warming temperatures associated with climate change are diminishing the region’s snowpack, with more precipitation falling as rain, rather than snow. That’s a problem because snowpack is a critical resource, acting as a natural reservoir that stores winter precipitation. Are we likely to face several low snowpack years in a row? Continue reading →

By Chris Schnepf

The Skeptical Science website outlines nearly 200 common climate change myths, and summarizes scientific responses to each assertion, with links to cited research. Screen shot from https://skepticalscience.com/argument.php.

One of the biggest challenges facing extension professionals is how to address climate change, especially in the context of people asking questions or making assertions that challenge climate science. Many of these questions have some kind of “gotcha” premise or multi-layered assumptions which must be pulled out and addressed individually to respond.

These kinds of questions are difficult to deal with even on comparatively simple topics like managing a specific insect pest, but they are even more challenging in an arena as complex as climate change, especially since many extension educators do not have as much depth of training as they do in a specific discipline such as agronomy or forestry.  Continue reading →

By Chris Schnepf

Halofsky, Jessica E.; Peterson, David L.; Dante-Wood, S. Karen; Hoang, Linh; Ho, Joanne J.; Joyce, Linda A., eds. 2018. Climate change vulnerability and adaptation in the Northern Rocky Mountains (Parts 1 and 2). Gen. Tech. Rep. RMRS-GTR-374. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station.

Foresters were among the first to start thinking about the possible effects of climate change, in part because of the long-term nature of forests—foresters commonly reflect on management issues on 50 or even 150-year time scales. Because forests are also highly valued for other benefits in addition to commodity production (i.e., wood), those managing forests are also particularly aware of the long-term effects of their management on water, wildlife, soil, and other ecosystem benefits.

One of the best examples of that broad, long, view is a recent new publication titled “Climate Change Vulnerability and Adaptation in the Northern Rocky Mountains,” a two-part, 495-page document produced by the USDA Forest Service). The publication is the result of a process that had extensive involvement from Forest Service personnel, non-governmental partners, and universities in a series of 2- and 3-day workshops throughout the Northern Region of the Forest Service (including one in Coeur d’Alene, Idaho). Continue reading →

By Chris Schnepf

“Nature’s Notebook” is an app that can be used to collect phenology data such as flower timing. Photo: C. Schnepf.

Trying to understand how climate is changing, and how these changes affect the crop yields, forest growth, water from melting snowpacks, and all the other parts of our natural world, is very challenging. Increasingly, some of the primary tools for understanding these phenomena are models.

One of the biggest misconceptions about models is the idea they are not based in the real world – that they are just theoretical constructs, untethered to actual measurements. There are models like that – even philosophers are playing with models these days. But most of the models used in the natural sciences depend on empirical data – measurements of things like temperature, precipitation, crop yields, tree mortality, and many other attributes. Continue reading →

By Sonia A. Hall

Irrigated pasture in Blaine County, Idaho. Water demand for irrigation is expected to start earlier in the season as the climate changes. Photo: Mark Goebel under CC BY 2.0.

Turns out that understanding how changes in climate are affecting the demand for water for irrigation in the Columbia River Basin is really important for our overall understanding of how water use and management may need to change in the future. Check out this Washington State University newsletter article on a recent study into this topic, led by AgClimate’s sometime-contributor Kirti Rajagopalan.

Reference:

Rajagopalan, K., Chinnayakanahalli, K.J., Stockle, C.O., Nelson, R.L., Kruger, C.E., Brady, M.P., Malek, K., Dinesh, S.T., Barber, M.E., Hamlet, A.F. and Yorgey, G.G., 2018. Impacts of Near‐Term Climate Change on Irrigation Demands and Crop Yields in the Columbia River Basin. Water Resources Research, 54(3), pp.2152-2182. https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/2017WR020954  

By Sonia A. Hall

Landscapes west and east of the 100th meridian. Left: Rangeland country in Idaho. Photo: Sonia A. Hall. Right: Soybean crops in Iowa. Photo: Parshotam Lal Tandon, under CC BY-NC-SA 2.0.

The contrast between the arid west—rangelands, wheat, conifer forests, irrigated agriculture—and the Midwest’s Great Plains—corn, soybean, prairies—is well known. There is a somewhat abrupt line separating arid from humid, close to the 100^th meridian. That line is now shifting, as climate change affects temperatures, precipitation, and wind patterns that control that arid-to-humid line. Take a look at a recent study from Columbia University on how the line is shifting eastward from the 100^th meridian. And you might want to start with the blog article “The 100th Meridian, Where the Great Plains Begin, May Be Shifting.”

References:

Seager, R., N. Lis, J. Feldman, M. Ting, A.P. Williams, J. Nakamura, H. Liu, and N. Henderson, 2018: Whither the 100th Meridian? The Once and Future Physical and Human Geography of America’s Arid–Humid Divide. Part I: The Story So Far. Earth Interact., 22, 1–22, https://doi.org/10.1175/EI-D-17-0011.1 

Seager, R., J. Feldman, N. Lis, M. Ting, A.P. Williams, J. Nakamura, H. Liu, and N. Henderson, 2018: Whither the 100th Meridian? The Once and Future Physical and Human Geography of America’s Arid–Humid Divide. Part II: The Meridian Moves East. Earth Interact., 22, 1–24, https://doi.org/10.1175/EI-D-17-0012.1