What is a high pressure system?
It’s almost as if the Earth knows that it is almost Halloween.
A scary oceanic and atmospheric phenomenon, christened “The Blob” by Washington climatologist Nick Bond some five years ago, has returned.
First observed in the northeastern Pacific Ocean in late 2013, the blob is a large area of warm water with temperatures 3 to 4 degrees above long-term averages.
It persisted for about three years, and scientists believe it to be the cause of problems for the environment and economy of the Northwest and beyond.
The pattern broke down in 2017 when a cooler and wetter regime returned for a year.
But now the blob is back.
Climatologists have spotted another huge area of warm water stretching from the northern mid-Pacific Ocean above the Bering Sea into the Arctic Ocean, east to British Columbia, and south along the West Coast nearly to Mexico.
It’s important because much of the weather in the Pacific Northwest comes from that region.
While this new blob has only been in existence for a short period, if it is anything like its predecessor, then the stage may be set for some similar effects.
The weather phenomenon forms when a persistent ridge of high pressure warms surface water in the Pacific.
The original blob, which occurred in tandem with a strong El Nino, coincided with 2015 being the hottest year on record in Washington and around the Northwest. That year also had a mild winter and low snowpack, and was followed by the hottest summer on record.
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.
Researchers from the University of California have detailed the widespread changes in the biology in the ocean and coastal ecology that were observed during the blob. Their reports document links to a series of animal illnesses and deaths, big algal blooms and a variety of marine oddities.
Dozens of large whales were found dead in 2015 and 2016 in the Gulf of Alaska, an occurrence that federal regulators designated formally as an “unexplained mortality event.”
Tens of thousands of dead common murres were found on Gulf of Alaska beaches and in inland areas. It is believed to be the biggest die-off of that species.
An unprecedented die-off of over 200 tufted puffins was discovered on St. Paul Island in the Bering Sea.
Sea otters in Kachemak Bay were found sick or dead from what appeared to be algal-produced toxins; misshapen and dead sea stars were also found in places that were once thought to be too cold to harbor the wasting disease that has been killing sea stars in more southern waters.
Problems were identified down the West Coast where thousands of starving sea lion pups turned up stranded on the California coast, prompting another unusual mortality event designation by federal officials.
“The warm water is not just a surface phenomenon along the top layer of the sea,” said Bond, an assistant professor at the University of Washington. “It reached about 80 meters in depth off Alaska and 200 meters in some spots off the West Coast.”
Assistant state climatologist Karin Bumbaco said, “The current blob has been closely tied to the dry weather we’ve experienced in Washington state. But since the ocean will respond quickly to changing weather patterns this time of year, I don’t expect the warmer ocean temperatures to impact our seasonal weather at this time.”
Bumbaco, a research scientist at UW, said several storms on the horizon this week and into next could break up the pattern of the warmer temperatures.
“The outlook beyond that is for a quieter weather pattern,” she said.
The latest winter forecast from the NOAA is predicting a mild, warmer winter with above average temperatures and precipitation in most of the Pacific Northwest.
Warm ocean water is known to affect different sub-regions in the Northwest differently. Warm water off North America’s West Coast usually is detrimental to salmon runs. In the Gulf of Alaska, it affects Pacific cod. When the Bering Sea is warm, there are changes in the distributions and survival rates for walleye pollock, and the benthic community is less productive.
Bumbaco said the blob is believed to be related to, but not necessarily caused by, global warming and climate change.
“Global warming has caused a slow upward temperature trend in the world’s oceans, including the North Pacific,” she said. “The blob of 2013-16 and the more recent event would not be nearly as large without that baseline warming.
“We are expecting a weak ElNino to develop this winter. Our winters tend to be on the warmer and drier side during ElNino events, particularly after Jan. 1, which would mean we have less snowpack by April 1, 2019.”
Sea surface temperature anomaly maps are available at NOAA’s Earth Systems Research Laboratory website at bit.ly/2AwtO0D.
“An interesting aspect of the present event,” Bond said, “is illustrated by clicking on the ‘seasonal loop’ under the ‘Latest Monthly Product’ on the second row. Specifically, this loop shows that the present anomalies in the Gulf of Alaska really strengthened in the last month or so.
“It is a really good example of why real-time monitoring is so important.”
Paul Krupin is an outdoor enthusiast and a member of the Intermountain Alpine Club (IMAC). He can be reached at firstname.lastname@example.org.