How would you like to enter a time machine and experience the weather of 50 years from now?
Interestingly, many of you have already done this and haven't realized it.
I am talking about this summer's warm weather in the Pacific Northwest.
Many locations on both sides of the Cascades experienced their all-time warmest temperatures for July and August and although it is not official yet, several locations, on both sides of the Cascades will have their all-time record summer (June 21-Sept 21) temperatures. As I noted in my earlier blogs, this warmth appears to be the result of natural variability, which created persistent high pressure over the eastern Pacific last fall. Not anthropogenic global (or local) warming.
How warm has the last three months been? Here are the temperature anomalies (difference from normal or climatology, generally the 1970-2000 is used for climatology today) over the past 90 days for Washington and Oregon (note the scales are a bit different in the figures). Nearly all of these states have been well above normal; averaging roughly 3F above normal, with eastern Washington more like 3.5F above normal
Now how far in the future would you have to "time travel" for such temperatures to be normal?
To be put it differently, how far in the future will the average summer be like the summer we just went through?
The UW Climate Impacts Group has published a report outlying their prediction of the future Northwest climate. Here is a figure from that report showing predicted temperature change (relative to 1960-1989) with time. They show the warming from various scenarios or RCPs (Representative Concentration Pathways). RCP 8.5 (solid red line) is the most aggressive. For reasons that I won't go into, many of my climate colleagues believe it it too aggressive and the RCP 4.5 (blue line) will prove closer to what will happen. Actually, a number of model simulations were made, with the solid lines being the average of many runs (the range of these simulation is shown by the lighter lines).
Reading off the graph, it looks to me that a 3F warming from 1970-1999 would be about a rise from roughly .5 F during 1970-1999 to 3.5 F around 2050. Quite frankly, even if we choose the more aggressive RCP 8.5 scenario the answer would not be that much different (maybe 2045).
Bottom line: the warm summer we have experienced is very much like the average summer around 2050.
Thus, we all have been time travelers, experiencing the average weather roughly 35 years into the future! Congratulations, time traveler.
Is the warming we experienced a good or bad thing?
I will let each of you decide for yourself. For my tomatoes, it has been a good thing. For my desiccated lawn, a bad thing. For those who like sustained warmth and sun, a good thing. Those who long for Northwest clouds and cool weather, a bad thing.
When I was a kid, one of my favorite TV shows was the Time Tunnel.
I do have an editorial comment that will undoubtedly get me into trouble. When folks talk about climate change and more specifically global warming, it is always described in negative terms. I was at the Northwest Climate Conference at the UW two weeks ago. NO ONE mentioned a single positive attribute of a warming climate here in the Northwest.
Yes, rapid climate change is often (and perhaps generally) negative for fauna, flora, and people accustomed to the current climate, but is there nothing positive about a cool, cloudy part of the U.S. getting a bit warmer? God knows, I am going to get a lot of flack saying this, but there it is....