- A massive marine heat wave is developing in the Pacific Ocean and is already threatening coral reefs near Hawaii.
- A few years ago, a similar and more powerful heat wave named the “blob” caused destroyed coral and disrupted marine food chains and fisheries along California and Hawaii.
- The current heat wave is the second-largest and longest marine heat wave in the northern Pacific Ocean ever that NOAA has ever recorded.
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Around five years ago, a large blob of heat plagued the Pacific Ocean, leading to die-offs, algal blooms, and coral bleaching.
Now it’s looking like the blob could be back. A mass of heat stretches over the Pacific Ocean, reaching from Hawaii to Alaska and California. This new blob has already bleached coral in the Hawaiian islands and stranded marine mammals on California’s coast, the Washington Post reported.
Right now, water temperatures surrounding Hawaii are around three degrees higher than normal, making this heat wave the second-largest and longest marine heat wave in the area since NOAA began tracking such events in 1982.
Coral reefs absorb nearly all of a wave’s energy, protecting coasts from storms, and provide habitat for one-quarter of all marine life. In the last 30 years, 27% of the world’s coral has been lost because of warmer temperatures and climate change.
Coral bleaching and food chain disruption in the Pacific
The first heat wave that took place in 2014 and 2015 caused major coral bleaching in the region.
Now, just four years after the first blob nearly killed off half of the coral on Hawaii’s coastline, another round of hot water could come back and cause even more destruction. Researchers are already beginning to spot signs of early bleaching due to record-high temperatures, the Post reported.
Coral bleaching has to do with coral’s relationship with algae. Healthy coral exists in a symbiotic relationship with algae, which live in the coral’s tissues and provide them with food and their bright colors. But when coral is stressed, whether that’s due to ocean temperature change, pollution, or too much sun exposure, the algae are expelled. Coral is left pale, fragile, and susceptible to disease.
The damage to coral reefs in Hawaii isn’t the only thing to worry about. The last blob caused the largest algal bloom recorded on the West Coast, the stranding of thousands of sea lions on beaches, and multiple fishery disasters, according to NOAA.
The impacts of these marine heat waves trickle throughout the food chain – if juvenile salmon, for example, can’t get a hold of nutritious food because rising temperatures are killing it off, then those populations decline. As populations of fish die, their predators, like orcas, sea lions, or humpback whales move closer to the coasts, risking getting trapped in fishing lines and crab traps, NPR reported.
Nick Bond, an atmospheric scientist at the University of Washington credited with coining the “blob” moniker, told the Post that the last event caused “a litany of horrors,” like dead sea birds washing up “in piles” along beaches in Washington state.
Will heat wave ‘blobs’ become more normal?
This summer, ocean temperatures were the hottest on record around the Hawaiian Islands, the Post reported.
Whether or not this blob will have the same level of impact as the first one that ravaged the Pacific Ocean is up in the air – NOAA research oceanographer Andrew Leising told the Post that the warm waters only extend for around 65 feet into the ocean, compared to the nearly 400 feet in some spots of the last blob.
Climate change’s role in these heat waves essentially amps up their intensity. As global warming increases, just like heat waves on land get more intense, so do heat waves over the ocean.
“In a warming world, these events are going to become worse, and we are going to head toward a state where it is like a permanent marine heat wave,” Hillary Scannell, an oceanographer at the University of Washington, told the Post.