Pacific Northwest
Washington State
January 9, 2016
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As many of the readers know, the West as well as other parts of the world has experienced significant drought this past few years and particularly this past year. Washington State and the Pacific Northwest were no exception. Its usual watershed, the mountain snow-pack, was at a long time low over the past summer. This low reserve was not from lack of precipitation per se which was close to normal State wide. Rather, it was due to warmer temperatures such that much of the winter precipitation fell as rain which in turn melted what snow was there.
Many people are ascribing these warmer temperatures and the resultant drought to the early effects of climate change. But, is this so? Was this lack of significant snow pack that typically fills our reservoirs and rivers due to climate change and global warming? This diary takes a look at the drought and its possible causes.
Opinions vary on this question. Here I present some views and information written recently on this issue with a focus on Washington State and particularly, Western Wasington. (I believe Oregon had a very similar experience.) I am not advocating that this specific year’s drought was due to global warming because, although I can read: “I am not a meteorologist or climatologist.” However, I will quote and cite recent writings of some of our local experts, including The Washington State Climatologist. In particular, two scientists who speak and write often on this subject are:
Dr. Nick Bond, Washington State Climatologist and Senior Research Scientist with the Joint Institute for the Study of Atmosphere and Ocean at the University of Washington, and
Dr. Cliff Mass, Professor of Atmospheric Sciences at the U. of W. and owner of the very popular “Cliff Mass Weather Blog.”
These scientists are also contributors to the recently published State of Knowledge Report: Climate Change in Puget Sound, (Climate Impacts Group), College of the Environment, University of Washington.
It Was a Strange Weather Year
To begin I would like to point out a few things on which most everyone agrees. Basically this past year’s weather in the PNW was “anomalous” – downright strange.
It was Hot:
Early in the year and through the summer, 2015 was very warm and dry resulting in a significant diminution of snow pack in the Cascade and Olympic Mountains. Locally it was indeed warm. Sea-Tac Airport, as a proxy for weather in Western Washington, recorded the warmest year in their recording history and the greatest number of hot days. The average temperature for 2015 was 55.66° F, surpassing the previous record of 54.99° F, set in 2014. (Note two record breaking summers in a row.)
It was Dry:
The lack of rain during the summer in particular resulted in US Drought Monitor designating all regions of the State as being in degree of drought.
It was wet and snowy:
By the end of December, 2015 had become the second wettest year on record at Sea-Tac Airport registering nearly 45 inches of rain, significantly above the average recorded rain fall of 36.85”, although less than 2014 of with 48.34”. With this rain and mountain snow, the drought conditions were declared over.
From Cliff Mass’ Weather Blog, December 26, 2015:
The U.S. snow depth analysis shows a dramatic picture this morning: huge amounts of snow over the Northwest U.S., but virtually nothing over the Northeast U.S. (see below). Washington State has greater depths than any other state (mainly in the Cascades), with amounts exceeded only by British Columbia, the Saudi Arabia of water resources.
By the end of 2015, our drought conditions had disappeared and we were no longer officially in drought. The snow pack was very high and reservoirs were nearly full. Compare the various photos of the twin sisters, taken in September, December, and January.
What caused this anomalous weather from severe drought to being out of drought in just a couple of months?
Was this normal or random fluctuations of weather phenomena, standard el nino weather, or is it due to Climate Change?
To address this question we can bring in our atmospheric Scientists. Both concede that there was no single explanation for this weather anomaly. Several factors contributed to this highly variable weather.
Our relatively warm weather for the past couple of years is attributed in part to large mass of warm ocean water that hung out in north Pacific just off Oregon, Washington, and the Gulf of Alaska. Nick Bond dubbed this mass of warm water, “The Blob.” This blob channeled warm air westward to the PNW. This warmer water accounts also for the numerous reports of tropical fish appearing further north that ever before.
The Blob as of April, 2014
Further, this warm blob was maintained by an area of persistent high pressure over the Eastern Pacific that diminished storms to our region. However, now the blob is dissipating and is nearly gone.
So why are we now getting the moisture more typical of our region?
From Cliff Mass’ blog:
Why is the BLOB dead? Because the mother of the BLOB--an area of persistent high pressure over the NE Pacific--is gone. The high pressure was associated with light winds, which did not produce the normal mixing in the upper layers of the ocean. Plenty of mixing this year, which brings up cooler water from below.
In addition, this is a particularly strong el nino year that directs “atmospheric rivers” toward us from the equatorial eastern Pacific. Some have suggested that what is left of the Blob might moderate the effects of the el nino.
Is This Climate Change?
Can our recent increase in temperatures and rain fall be attributed to the effects of global climate change? Not yet according to Bond and Mass. While acknowledging the recent relatively extreme weather events, Bond states:
To be sure, there is considerable temporal and spatial variability in these trends, and the inherently “noisy” nature of time series of extreme events complicates attribution to climate change. Nevertheless, present climate models are suggesting that heavy precipitation events will increase in magnitude (by very roughly 20% on average) and frequency (by as much as four-fold) by the 2080s relative to the latter part of the 20th century
And Mass states (Oct. 16, 2015):
So the main reason that we were so dry and warm (the eastern Pacific High pressure) is now gone. And furthermore, its direct offspring, the BLOB (the area of warm water off our coast), is rapidly weakening. The blob and the high pressure area that spawned it are going and gone.
Specifically, we endured substantially (2-4C) warmer than normal conditions, record low snowpacks in our mountains, record low streamflows, and slightly below normal precipitation--very much like anthropogenic global warming will probably produce in our region during typical summers in 60-70 years. Keep in mind that the best science indicates that the CAUSE of the warming this year was not from increasing greenhouse gases but from natural variability, variability that produced a high amplitude, persistent ridge of high pressure over the eastern Pacific.
Some will be quick to blame global warming from increasing greenhouse gases, but that is an unlikely explanation of a sudden, one-off year like this. Greenhouse gas induced changes would be expected to develop more gradually.
My interpretation of what Bond and Mass are saying is that while acknowledging that we have had peculiar weather patterns of late, we can’t attribute them to climate change. In the same way that we can not use the fact of our huge snow pack at the present to deny global warming, neither can we use last year’s heat and drought to confirm global warming as there are local factors within the range of normal variability that can account for them both. Nonetheless, these scientists clearly acknowledge that global warming is in our future and poses significant threats on many fronts to our region as well as the world.
Cliff Mass wrote on Oct. 26th:
The biggest environmental issue of our day is not global warming but sustainability: how can the human species reach a long-term, sustainable relationship with our planet? Sustainability is controlled by population, use of resources, the climate of the planet, water resources, and much more.
But clearly, global warming is a very serious part of sustainability, with our best science indicating that the planet will warm substantially during the next century as a result of increasing greenhouse gases like CO2. The environmental community and its allies in the political realm have made global warming their number-one environmental priority.
QUESTIONS?
Although I follow what these scientists are saying relative to the causes of our recent weather anomalies, I still have some unanswered questions concerning global warming and climate change.
If, as these atmospheric scientists postulate, our recent odd weather is a hint of what we might expect to experience in the the next 50 years or so, but is not yet causing global climate change, how then can we explain the current rapid melting of the Greenland and Arctic ice packs and the receding glaciers? Can the arctic melt be due to climate change while our local glacial melting is not? How can we reconcile these observations?
On December 22nd, I asked Cliff Mass on his blog this very question but did not receive an answer from him.
I would love to hear how others on Daily Kos who are more knowledgeable than I on this topic might answer my question.
How is your backyard faring relative to the (pending?) climate change ?
Addendum:
I did however, receive a rather detailed response from a Weather Blog reader along with references shown below. This writer is regionally well known as a Climate Change denier as you will be able to tell immediately from his comment. Here are a few excerpts from his response to my question. The answer in his mind is very simple. There is no global warming as in climate change. Period. I am not inclined to buy his program. Read below if you would like to see a GW denier in action.
Melting of Greenland Ice -- NASA satellite temperature measurements for the Arctic show zero or slightly cooling temp change for the past 13 years 10 months. Ground weather stations in Greenland show temperatures less than they were in the 1930s.
Alaskan glaciers -- Most Alaskan glaciers advance during the 1950-1977 cool period, then retreated during the 1978 to ~2000 warm period. Temperatures have been generally cooler the past decade and some glaciers are now beginning to advance.
Cascade glaciers, notably Mt. Baker and Mt. Rainer, advanced strongly during the 1950-1977 cool period, retreated during the 1980-~2000 warm period. NOAA temp data show cooling temperatures for the past decade and some glaciers have stopped retreating and advanced slightly from 2013-2015. For data, see wattsupwiththat.com/…
NASA satellite temperature records for the globe, north polar, south polar, Southern Hemisphere, tropics, US conterminous 49 states, and Australia all show no warming for anywhere from 18 to 37 years. You can check this out for yourself at
www.climatedepot.com/...
So, there is quite a range of views out there from: The global temperature has not changed for maybe 37 years — the current weather variability is due to more local factors but show us what our climate will be like by the 2080s, and then, that our anthropogenic greenhouse gases are already causing the earth to warm, creating social and economic difficulties.
To the extent that either of the last two scenarios are accurate, we have much work to do to mitigate the coming dire effects of GW. I am pleased to see our State taking constructive steps to prepare for the coming changes as detailed in the new report mentioned above: State of Knowledge Report: Climate Change in Puget Sound.