National Climate Assessment
May 19, 2014
By Chad Kruger
The US Global Change Research Program released the Third National Climate Assessment a couple of weeks ago. Unlike some other recent climate report releases (USDA’s Climate Change and Agriculture Report, the Northwest Climate Assessment and the IPCC AR5 Draft Report), this one seemed to have been picked up to a much greater extent by the major national and regional news agencies. In fact, I’ve been interviewed by two separate NPR reporters in the region for my interpretation on what the Assessment means for PNW agriculture. Part of the reason for the media attention likely stems from the much more aggressive promotional messaging – specifically stating that climate change is hurting the economy now (I’ll have more to say on that idea in a future post).
So what does the NCA have to say about PNW agriculture? This is the primary question that I’ve been asked by reporters and others over the past two weeks.
The short answer is “not much”. The Northwest chapter (written by several of my colleagues) briefly touches on the impacts on mountain snowpack (important to irrigation water supply) and the somewhat positive impacts we may experience on crop yields in the region, while pointing out that there are many remaining questions regarding impacts to sustainability and conservation. A much more detailed description of these findings was described in the Northwest Climate Assessment released last year and that I have described in other posts, as well as a webinar in late 2012.
I think the more interesting consideration that emerges with the National Climate Assessment is how different the results are for PNW agricultural projections than they are for the rest of the US. The Agriculture chapter largely focuses on generalizable trends at a national level with a few specific case studies to further illustrate points. The reality is that our prior work indicates that the PNW is something of an anomaly relative to the nation in that we project to experience something of a buffer from more negative impacts due to our relative latitude and the fact that we have a predominantly “C3 photosynthetic pathway” production system (including wheat, apples, and potatoes) which benefits from elevated atmospheric CO2.
Our well-established agricultural vulnerability is irrigation water supply in specific locations – but that is a concern we face regardless of whether future climate changes or not. Changing climate may intensify the deficit of water availability in certain locations, but we really have a pretty good handle on what that vulnerability looks like and there are many ongoing efforts to address it.
When you compare PNW agriculture projections to national projections (or global) it becomes very clear that we are in much better shape here than most of the rest of the country. In fact, it’s plausible that changes in domestic and global agricultural markets due to climate impacts elsewhere may have more meaningful impacts on PNW agricultural systems than the direct impact of climate itself – at least in the near future.