Warm waters in the North Pacific Ocean have some atmospheric scientists speculating The Blob is getting the band back together, and that possibility is sparking all kinds of speculation about West Coast weather and salmon.
University of Washington Atmospheric Sciences Professor Cliff Mass started discussions off with a Oct.16 post on his weather and climate blog with the declaration “The Son of Blob is Back!” and a graphic reference to the old Blob movies.
“The blob is back in a horrifying new adventure, and you there, started, stunned, terrified, as the blood red creature rolls over and eats everything in its path…Beware The Blob,” Son of the Blob, 1972.
“If you dare to look, let me illustrate our scary situation” is how Mass then teased the present 2 degree Centigrade (3.6 degree F ) warmer than normal temperature in the Gulf of Alaska.
Journalists around the Pacific Rim were quick to jump in, though there are some climatologists skeptical this warm water event is going to last.
As one observed in an email to colleagues, September temperature data taken during a cruise through The Blob indicated “that the above average temperatures only extend to about 30 meters (approximately 98 feet) in the water column so this ‘Son of the Blob’ might be prone to breakdown from the return of normal fall storms and winds.”
But that hasn’t slowed the natural human desire to speculate on the future because everyone wants to know what the future holds: you, me, other journalists, scientists, everyone. It’s hard to avoid engaging in speculation, but even when it is highly informed speculation, it is still speculation.
Still, it’s fun.
“I guess it’s apropos this Halloween ‘scary movie’ season that just when you thought a meteorological villain was totally vanquished a few years ago, here comes the sequel,” Scott Sistek reported midmonth at KOMO News in Seattle.
“…The Blob (in tandem with one of the strongest El Nino’s on record) was blamed for contributing to 2015 being the hottest year on record in Seattle, featuring a very mild winter (the final sub-50 degree high temperature that year occurred on Feb. 1), a very low mountain snowpack season (Snoqualmie Pass had just 104 inches of seasonal snow, about a quarter of normal) transitioning to the hottest summer on record (although that was nearly matched this past summer),” he wrote.
Bad if you were a skier. Generally good if you were not, although it is politically incorrect to think of global warming – localized, isolated or otherwise – as good.
“First observed in the northeastern Pacific Ocean in late 2013,” he reported. “It persisted for about three years, and scientists believe it to be the cause of problems to the environment and economy of the Northwest and beyond.
“The duration and persistence of the previous blob has been studied by scientists in Washington and the National Oceanic and Atmospheric Administration, who documented the ways the anomaly coincided with a variety of unusual biological events and species sightings.
“These included low returns of salmon, and die-offs of sturgeon, bird populations and other wildlife, all believed to be directly related to the excessive temperatures observed.”
Only the situation wasn’t quite as simple as Krupin makes it out to be. Those low returns of salmon were limited to the Pacific Northwest. Alaska prospered during The Blob years – 2013 to 2016.
The 49th state witnessed a historical record harvest of 272 million salmon in 2013. The catch dropped to 158 million the next year, but rebounded to 263.5 million in 2015, the second largest catch in history.
The yo-yoing continued going forward with the 2016 catch plummeting to about 110 million, and the 2017 catch (the young fish of which spent their time at sea in a fading blob) climbing back up to 225 million, the third highest catch on record.
The five-year average harvest through The Blob years came to about 205 million salmon per year. No period in Alaska history comes close to that kind of production.
The difference between these two, five-year periods – about 31 million salmon – is greater than the entire, statewide harvest of 26 million in 1975 when the state was in the middle of enduring a string of years with unusually cold water in the Gulf of Alaska
The harvest this year was down to about 110 million, keeping with the pattern of small, odd-year catches following big even-year catches, and some were blaming The Blob, which got no credit for the big catches in 2015 and 2017.
Twenty-thirteen should probably be discounted as a Blob year in terms of salmon returns because the warm-up came late, and young salmon were little exposed to it. But there are facts to consider as well.
The definitive study on salmon and water temperatures concluded that experimental results “suggest that over a relatively broad range of temperatures and feeding rates, the direct thermal effects of climate change (warming) on growth are relatively minor, compared to the effects of differences in feeding rate or prey quality caused by climate-induced changes to the species composition and productivity of the water masses inhabited by salmon.”
U.S. Geological Survey, Western Fisheries Research Center scientist David Beauchamp and colleagues in a 2007, peer-reviewed paper – “Bioenergetic Responses by Pacific Salmon to Climate and Ecosystem Variation” – concluded that within a window of about 20 degrees from water temperatures of 46 to 66 degrees salmon did fine if adequate food is available.
But the main takeaway from the Beauchamp’s study is that when it comes to salmon nothing is as simple as “The Blob” or no Blob. It’s all complicated.
“…(The) feeding rate or large shifts in prey quality would affect growth much more than a several-degree shift in temperature when near the optimal growth temperature, whereas temperature would become an increasingly important influence on growth if fish already occupied the cooler or warmer marginal temperatures,” he wrote.
“Moreover, temperatures and food supplies that might limit growth for older, larger life stages might not limit growth for smaller salmon. Thus, the energetic response to climate or ecosystem change could differ significantly among species and life stages of salmon because of their unique physiological responses to the thermal regime, their ability to utilize the available and exploitable food resources, and how their time and energy budgets are affected by the localized density and distribution of prey, competitors, and predators.”
How The Blob drives North Pacific weather, or how North Pacific weather drives The Blob, is simpler, but not a lot so. Mass and other atmospheric scientists agree The Blob is the result of a persistent block of high pressure-air centralized over the Gulf.
“As shown by my colleague and BLOB meister Dr. Nick Bond and his co-authors, persistent high pressure is associated with lighter winds,” Mass wrote. “Such light winds result in less mixing in the upper layer of the ocean, so less cooler water from below is mixed to the surface.”
The high pressure is, in turn, being held in place by an atmospheric ridge of air along the West Coast of North America, but why the weather pattern is setting up in this way – as it did in 2017 to bring December rains to much of coastal Alaska – nobody seems to know for sure.