I remember the first modern scientific paper about climate change in the early '90s. In 2006, my partners and I started
Central Washington Biodiesel, partly out of concern about climate change, and in 2011 I went to my first
scientific conference about climate change. In 2012 I organized TEDxTheEvergreenStateCollege: Hello Climate Change. One talk from that event,
Climate Change is Simple, by David Roberts, has a total of about 200,000 views on YouTube.
Also in about 2012, this video really grabbed my attention. It was put together by Richard Muller, previously a climate change skeptic. His organization, which has received Koch brothers funding in the past, is called
Berkeley Earth.
I set this version so that it starts in about when I was conceived, for maximum effect.
I'm not an expert, but I have been paying attention to climate change for quite some time. The good news is that there is mostly good news when it comes to the effect of climate change in the Pacific Northwest region. The same is generally true for Kittitas County. There is a little not-so-good news, too, for our region. Unfortunately, the news for large parts of the planet is almost all bad, so I'm going to focus on Kittitas County and the PNW here.
In his TEDx talk, David Roberts covers the simpler, broader parts of climate change in about 17 minutes, but this is going to be a longish blog post about more local issues. Toward the bottom of the post, I'll write about some possible policy implications.
First, we need to mention that science is uncertain, and there's no way around it. There are many different levels of uncertainty. There's always a chance someone in the last stages of cancer could recover, or that what looks like a tumor on the first visit to a doctor turns out not to be a tumor. It is technically possible that climate change isn't really happening, but there is lots of evidence from many different sources that shows that it really is happening. Indeed, there is so much evidence that we should be behaving as if climate change is happening now.
Next, we need to talk about how weather and climate are not the same thing, and how there is a large amount of variability even over long periods. In this graph (also from the Berkeley Earth
website), showing temperatures in our area since records began in about 1835, it appears that our average temperature has risen by about a degree and a half Celsius (about 2.7°F). But a recent
paper provides a convincing argument that our local temperature increase is mostly due to normal regional variability, not anthropogenic (that is, human-caused) climate change. Put another way, in our area the effects of climate change so far have been smaller than the long-term variability of regional weather.
Make no mistake, on a global level anthropogenic climate change is just about as real a thing as we have in science, but warming happens at different rates in different places. Because we are right next to the eastern Pacific Ocean, where cold water comes to the surface from the deep ocean, our region is warming more slowly than other places.
As if all that wasn't confusing enough (the PNW has been warming, but not because of climate change; the rest of the world really is warming because of climate change), there's this past summer.
This map (from Cliff Mass's weather
blog) shows the departure from normal of air temperatures across Washington during the summer of 2014. In Eastern Washington, temperatures averaged about 3.5°F above normal. It was a record-breaking summer, but it was mostly due to natural variability and only a little due to climate change.
The greatest impacts to agriculture will come from changes in water availability, largely because farmers are already used to dealing with significant weather variability.
In the Kittitas Valley, our irrigation season is extended as snowpack in the Cascades melts during the summer. That is expected to change as the climate continues to change. (The next three figures are from the University of Washington Climate Impacts Group 2013 State of Knowledge Report on climate change impacts in the Northwest. The pdf is available
here.)
Areas that get their water from sources that are near the current snowline are the most sensitive to changes in average year-round temperature. That's because increases in temperature will raise the snowline above the mountain tops. That means our water supplies will be changing, and the effect is significant enough that the Yakima River Basin is specifically discussed in the Climate Impacts Group (CIG) report. These graphs follow the above figure in the CIG report. (Again, here's a
link to the pdf of that report.)
The middle graph shows monthly changes in Yakima River flows at three points in the future. Notice that our current maximum flow happens in June and July. In the future, maximum flow is expected to occur in December-February, because precipitation that now falls in the mountains as snow will fall as mixed rain and snow and later as rain during the winter.
The predicted changes in our water supplies are due to predicted changes in temperature. What does the future hold for us temperature-wise?
This graph show the predictions of climate modeling for the Northwest (it's Figure ES-3 in the
CIG report). It shows that our temperatures will likely rise by about 3.5 degrees by around 2050. As Cliff Mass points out, that's when the summer of 2014 will seem normal.