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‘The Blob’ Is Back: Unusually Warm Waters Along Pacific Coast Have Returned

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NewsDeeply

The Blob is back. Unusually warm waters along the Pacific Coast, dubbed “the Blob,” have severely disrupted weather and wildlife since 2014. Meteorologist Nicholas Bond explains the phenomenon.

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This illustration of temperature in the northeast Pacific shows the status of the “Blob,” a warm-water phenomenon, as of September 2016.Image courtesy NOAA

Since 2014, a mass of unusually warm water has hovered and swelled in the Pacific Ocean off the West Coast of North America, playing havoc with marine wildlife, water quality and the regional weather.

Earlier this year, weather and oceanography experts thought it was waning. But no: The Blob came back, and it is again in position off the coast, threatening to smother normal coastal weather and ecosystem behavior.

The Blob isn’t exactly to blame for California’s drought, though it certainly aggravated the problem. But it is to blame for seriously disrupting the ocean food chain and for creating conditions that fed unprecedented algal blooms in the coastal Pacific.

With the Blob back in play again, what does it mean for the winter ahead? To find out, Water Deeply spoke with Nicholas Bond, a research meteorologist at the University of Washington in Seattle and Washington’s state climatologist. In June 2014, Bond named this persistent weather phenomenon, and later wrote the first scientific paper characterizing it.

Water Deeply: What exactly is the Blob?

Nicholas Bond: It’s a large mass of water in the northeast Pacific Ocean that’s considerably warmer than usual. It doesn’t have any real sharply defined boundaries, but it’s an area that, at times, has stretched from Baja California up to the Bering Sea. At other times, it’s kinda shrunk back down. It’s been at least 1,000 miles (1,600km) across and, recently, quite deep.

Typically, it’s been something like 2.7–3.6F (1.5–2C) warmer than normal. But there have been places where it’s been as much as 9F (5C) warmer. It’s waxed and waned, but it’s been that way since early 2014. The warmer-than-normal water extends down to something like 300m (1,000ft) below the surface. So that’s a huge volume of considerably warmer-than-normal water.

Water Deeply: Is it still out there?

Bond: Yeah. There was sort of a reinvigoration this past summer. The temperatures were moderating early in 2016, and then, at least in a large area south of Alaska and off the coast of the Pacific Northwest, it really warmed up again this past summer.

Emaciated juvenile sea lions undergoing rehabilitation at the Marine Mammal Center in California. Their plight is thought to have been triggered by the unusually warm water conditions that persist in the coastal Pacific Ocean, upsetting the usual food web upon which sea lions and other wildlife depend. (NOAA Fisheries)

Water Deeply: What causes it?

Bond: A lot of it, almost all of it, is due to just the unusual weather patterns that have been occurring over the northeast Pacific during the past few years. They haven’t been the same patterns, but what really got it started was when a ridge of higher-than-normal sea-level pressure set up during the winter of 2013–14 over the northeast Pacific.

That was a very persistent and strong ridge of higher-than-normal pressure that kind of blocked the usual parade of storms across the Pacific. That meant less heat was drawn out of the ocean into the atmosphere than usual. It meant there was less cold water (from the deeper ocean) mixing near the surface part of the ocean. And also the unusual winds meant the upper-level currents in the ocean were a little bit different from usual.

Water Deeply: Is it unprecedented?

Bond: Yeah, certainly. In terms of the magnitude of anomalies in a lot of locations, we haven’t seen anything quite like this. I did a fairly careful study using the data that’s available, going back decades. There have been other periods with considerably warmer-than-normal ocean temperatures in the region. But they were never of the kind of geographic extent and magnitude we’ve seen with this recent event. […]

Water Deeply: How long will the Blob be with us?

Bond: That’s kind of the $64,000 question. We thought this whole event was winding down earlier this year, and then we’ve seen it rear its ugly head again in some locations.

Water Deeply: How will this affect our weather this coming winter?

Bond: The more prominent temperature anomalies are a little north of California. It’s all going to depend on the weather patterns. There are kind of borderline La Niña conditions now, which doesn’t tend to imply too much one way or another for Northern California. In the past, it probably has meant somewhat less precipitation than normal for Southern California. But we see a lot of exceptions there.

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