Scientists monitoring new marine heat wave off B.C. coast similar to 'the Blob'

A new marine heat wave spreading across a portion ofthe Pacific Oceanoff the coast of British Columbiahas so far grown into one of the largest of its kind in the last four decades, officials say, second only to the infamous"blob" that disrupted marine life five years ago.

The swathof unusually warm water stretches roughly from Alaska down to California, according to the National Oceanic and Atmospheric Administration (NOAA) in the United States. The marine phenomenon began in the Gulf of Alaska sometime around June 15and balloonedover the summer.

A marine heat wave happens when sea surface temperatures are higher thannormal for at least five consecutive days.

Officials tracking the systemsaid it is already the second-largest experts have seen since 1981 the first year for which satellite data used to track marine heat wavesis available.

"Already, on its own, it is one of the most significant events that we've seen,"Andrew Leising, a research scientist at the NOAA's Southwest Fisheries Science Center in La Jolla, Calif.,said in astatement Thursday.

Above average water temperature

Leisingsaid this year's heat wave resembles a similar West Coast heat wave that upset marine life in 2014 and 2015. Nicknamed "theBlob," the system, which stretched from Mexico to the Bering Sea, was blamed forwarmer weatheron land,abysmalfeeding conditionsfor salmon andthe sudden deaths of two dozen whalesin the Pacific.

The Blob sawtemperatures in the water peak at 3.9 Cabove average. The NOAA said the water this year has already reached temperatures of more than 2.7 Cabove average off the coast of Washington state.

"It'son a trajectory to be as strong as the prior event," said Leising, whodeveloped asystem for tracking and measuring heat wavesin the Pacific Ocean using satellite data.

"It's really only time that will tell if this feature is going to persist and then rival [the Blob]."

The NOAAsaid its staff ismonitoring this year'ssystem to see whether it will last long enough to impact the marine ecosystem, though some biologists suggestit already has based on its sheer size.

The agency blamed the recent marine heat waveon a persistent weather pattern that began in June: weaker-than-normal winds and a weaker high-pressure systemover the wedge of warm ocean between B.C., Hawaii and Washington state.

Officials say aformal analysis to try topinpoint the reasons for the unusual weatherpattern will take "some months" to complete. During the previous "blob" event, a number of studies suggested long-term ocean warming due to climate change made the heat wave stronger than it otherwise would have been.

Cold water rising along the coast from the ocean depths has held the warmer wateroffshore thus far, but experts said the chilledsurge usually peters outin the fall. The heat wave in the water could move onshore and affect coastal temperatures if that happens, Leisingsaid in the statement.

Officials also noted the marine heat wave is still new enough tobreak upif the weather shifts.

"It looks bad, but it could also go away pretty quickly if the unusually persistent weather patterns that caused it change," wrote NOAA research scientist Nate Mantua.