September 7, 2023 — A tropical weather system called El Niño is beginning its march up the coast of Oregon, bringing with it a warmer winter and inescapable heat for some marine life.
Oregonians on the coast could experience flooding from high tides and rising sea levels. In the mountains, areas hoping for snow are more likely to get rain, which could accentuate the drought plaguing the West. For aquatic species, warming ocean temperatures could spur a northern migration and could be deadly for plankton vital to salmon and other species up the food chain.
Spurred by a change in air pressure over the Pacific Ocean near the equator, El Niño last visited Oregon in the winter of 2018, and has occurred more than 20 times since 1950.
It is both an ocean and atmospheric weather pattern that touches all parts of the West.
The latest system, which recently reached the southern Oregon coast, is predicted to be among the fiercest in years, according to Oregon’s state climatologist, Larry O’Neill. There have only been three El Niños since 1970 that have reached the category of “very strong” as determined by the National Oceanic and Atmospheric Administration. The last one was in 1997.
“Generally the rule of thumb is that El Niño leads to drier, warmer weather,” he said. “In strong years, it’s led to warmer, wetter weather. We don’t know yet how robust those relationships are though.”