Researchers at the Scripps Institution of Oceanography have recorded record-breaking daily high water temperatures off the coast of southern California over the past three months. At the La Jolla station, temperatures reached 10°F above the historical average last month, raising concerns about a prolonged marine heatwave.
The current warming is not driven by El Niño, but by a high-pressure atmospheric system that has settled above the region, creating calm, sunny conditions that have warmed both air and sea. This phenomenon is reminiscent of 'the Blob', a three-year marine heatwave a decade ago that devastated marine life. Scientists warn that the next few weeks will be critical in determining whether this event fizzles out or intensifies.
Prolonged ocean heat can disrupt phytoplankton growth, trigger harmful algal blooms, and impact marine species such as sea lions, dolphins, and fish. During the Blob, the Dungeness crab season suffered significantly. Marine heatwaves are becoming more frequent and longer-lasting due to climate change and atmospheric shifts that scientists are still trying to understand.
While warmer waters have brought tuna closer to shore and provided pleasant conditions for swimmers, researchers emphasise that the long-term ecological costs outweigh these benefits. 'Our ocean should not be a swimming pool,' said Melissa Carter of Scripps. 'Nothing can live in a swimming pool.'
