{"id":278426,"date":"2026-04-21T11:41:08","date_gmt":"2026-04-21T11:41:08","guid":{"rendered":"https:\/\/www.newsbeep.com\/us-ca\/278426\/"},"modified":"2026-04-21T11:41:08","modified_gmt":"2026-04-21T11:41:08","slug":"an-extreme-marine-heat-wave-simmers-off-californias-coast-right-now","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/us-ca\/278426\/","title":{"rendered":"An extreme marine heat wave simmers off California&#8217;s coast right now"},"content":{"rendered":"<p><img alt=\"A sunset crests over the Scripps Pier in La Jolla.\" loading=\"eager\" fetchpriority=\"high\"   style=\"aspect-ratio:3 \/ 2\" class=\"x100 y100 opc bgpc ofcv bgscv block bg-gray200 mnh0px fill\"\/><\/p>\n<p>A sunset crests over the Scripps Pier in La Jolla.<\/p>\n<p>Erik Jepsen<\/p>\n<p>Hottest. Earliest. Most extreme. California\u2019s meteorologists and oceanographers keep dropping new superlatives about the temperatures in 2026.\u00a0<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/cdn-channels-pixel.ex.co\/events\/0012000001fxZm9AAE?integrationType=DEFAULT&amp;template=design%2Farticle%2Fplatypus_two_column.tpl\" alt=\"\" class=\"x1px y1px vh abs\" aria-hidden=\"true\" width=\"1\" height=\"1\"\/><\/p>\n<p>In the first months of the year, a\u00a0<a href=\"https:\/\/www.sfgate.com\/weather\/article\/records-heat-wave-22081553.php\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">record-smashing<\/a> <a href=\"https:\/\/www.sfgate.com\/weather\/article\/calif-heat-wave-records-22080247.php\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">heat wave<\/a> set a new high for the <a href=\"https:\/\/www.sfgate.com\/weather\/article\/california-heat-wave-records-22086450.php\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">hottest California day<\/a> in March and <a href=\"https:\/\/www.sfgate.com\/bayarea\/article\/rattlesnake-bites-spike-22208190.php\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">prompted<\/a> a premature <a href=\"https:\/\/www.sfgate.com\/national-parks\/article\/national-parks-early-spring-22206897.php\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">spring<\/a>. Now, experts are turning focus to the heat simmering deep in the Pacific Ocean, which is already likely hurting\u00a0<a href=\"https:\/\/www.sfgate.com\/bayarea\/article\/seabird-deaths-california-22188219.php\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">marine life<\/a>.\u00a0<\/p>\n<p class=\"uiTextSmall f aic jcc\">Article continues below this ad<\/p>\n<p>\u201cThere\u2019s a bunch of claims circulating, some viral social media posts, that this is the most extreme heat wave, oceanic heat wave ever observed in this region, so is that true?\u201d Daniel Swain, a climate scientist for the University of California\u2019s Agriculture and Natural Resources, said\u00a0<a href=\"https:\/\/www.youtube.com\/watch?v=SIRF3D4-ccs&amp;t=9s\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">during a recent videostream<\/a>. \u201cWell, by many objective metrics, yes, that is correct.\u201d<\/p>\n<p>The Pacific Ocean is baking for thousands of miles, from about San Francisco all the way to Guatemala, according to recent\u00a0<a href=\"https:\/\/climateengine.org\/\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">sea surface temperature<\/a> data from the National Oceanic and Atmospheric Administration. In this data set, a massive splotch of dark maroon concentrated from California\u2019s Central Coast into Mexico \u2014 and also far west offshore \u2014 depicts many spots with temperatures ranking in the highest percentiles.\u00a0<\/p>\n<p>\u201cThe 100th percentile here would mean, for example, the single warmest value ever observed,\u201d Swain explained, \u201cand the 98 percentile means that only 2% of all historical observations were warmer.\u201d\u00a0<\/p>\n<p>Smack in the middle of this unprecedented marine heat, scientists from the Scripps Institute of Oceanography at\u00a0UC San Diego maintain one of the <a href=\"https:\/\/shorestations.ucsd.edu\/\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">most robust data sets for the sea<\/a>. They monitor daily temperatures at 10 coastal stations across California, including ones at the Scripps Pier, Newport Beach, Pacific Grove and the Farallon Islands with more than 100 years of data.\u00a0<\/p>\n<p class=\"uiTextSmall f aic jcc\">Article continues below this ad<\/p>\n<p>Since November 2025, many of these stations have broken daily, all-time record highs for water temperature, according to Scripps. Most readings have ranged upwards of 2 to 4\u00a0degrees\u00a0Fahrenheit\u00a0warmer than the high historical temperatures\u00a0for the time of year, <a href=\"https:\/\/scripps.ucsd.edu\/research\/climate-change-resources\/californias-marine-heatwaves\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">a significant rise for ocean waters<\/a>. Since Jan. 1, at least 36 days of temperature readings off the Scripps Pier broke daily records.\u00a0<\/p>\n<p><img alt=\"The red dots indicate the daily records broken at Scripps Pier in 2026.\" loading=\"lazy\"   style=\"aspect-ratio:3 \/ 2\" class=\"x100 y100 opc bgpc ofcv bgscv block bg-gray200 mnh0px fill\"\/><\/p>\n<p>The red dots indicate the daily records broken at Scripps Pier in 2026.<\/p>\n<p>Scripps Pier, La Jolla, Shore Stations<\/p>\n<p>Beyond the surface, there\u2019s evidence the warm layer extends far offshore and deep down as well, according to the Scripps scientists who send\u00a0<a href=\"https:\/\/spraydata.ucsd.edu\/about\/spray-glider\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">robotic underwater gliders<\/a> out to sea for months of exploration.\u00a0<\/p>\n<p>Deadly\u00a0heat\u00a0for marine life<\/p>\n<p>The deep-sea temperature rise is just shy of that during the infamous \u201c<a href=\"https:\/\/www.fisheries.noaa.gov\/feature-story\/looking-back-blob-record-warming-drives-unprecedented-ocean-change\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">blob<\/a>\u201d of warm water from roughly 2014 to 2015, which <a href=\"https:\/\/scripps.ucsd.edu\/research\/climate-change-resources\/californias-marine-heatwaves\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">led to a cascade of impacts on marine life<\/a>. Species like hammerhead sharks, bluefin tuna and red crabs traveled north; baitfish like anchovies thrived while sardines did not, affecting commercial fisheries; seabirds, seals and sea lions starved; kelp suffered; harmful algal blooms took off.\u00a0<\/p>\n<p class=\"uiTextSmall f aic jcc\">Article continues below this ad<\/p>\n<p>The current\u00a0heat wave is likely fueling the seabird\u00a0die-offs in Central and Southern California in recent months. Researchers in San Diego conducting monthly beach surveys for dead seabirds and marine mammals have found a spike in the numbers of dead brown pelicans, Brandt\u2019s cormorants and common murres.\u00a0<\/p>\n<p>\u201cIf the ocean is warmer than normal, it can impact the food web in multiple ways,\u201d Tammy Russell, a marine seabird expert at Scripps, said in a statement. \u201cFish and other organisms that require cooler waters to survive can move to cooler locations (north or deeper), resulting in lower food availability in warmer regions. Additionally, warmer conditions can stratify the water column, reducing the nutrient supply that reaches the surface waters and have cascading impacts on the entire food web.\u201d<\/p>\n<p>Since most of the birds look emaciated and test negative for HPAI, or avian flu, the scientists have concluded that starvation is driving the mortality event.\u00a0<\/p>\n<p class=\"uiTextSmall f aic jcc\">Article continues below this ad<\/p>\n<p>\u201cI think it\u2019s fair to say there are winners and losers in marine life, and a lot of that depends on whether an organism\u00a0can move or not,\u201d Dan Rudnick, a physical oceanographer for Scripps, told SFGATE. \u201cWhen we have warmer water, we\u2019ll see more species that prefer warmer water here, more tropical species off Southern California. On the other hand, some organisms that can\u2019t move will be worse off because they\u2019re adapted to colder temperatures. If it stays warm for a very long time, we can have kelp die-offs, for example.\u201d<\/p>\n<p><img alt=\"Jamin Greenbaum\u2019s RIFT-OX floating platform being tested off Scripps Pier in December 2025.\" loading=\"lazy\"   style=\"aspect-ratio:3 \/ 2\" class=\"x100 y100 opc bgpc ofcv bgscv block bg-gray200 mnh0px fill\"\/><\/p>\n<p>Jamin Greenbaum\u2019s RIFT-OX floating platform being tested off Scripps Pier in December 2025.<\/p>\n<p>Erik Jepsen\/UC San Diego<\/p>\n<p>Interactions with El\u00a0Ni\u00f1o\u00a0\n<\/p>\n<p><a href=\"https:\/\/www.sfgate.com\/weather\/article\/el-nino-forecast-22196520.php\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">El Ni\u00f1o conditions<\/a>, expected to develop later this year, could amplify the marine heat wave. El Ni\u00f1o is the warm phase of a pattern that emerges in the tropical Pacific Ocean, called the El Ni\u00f1o-Southern Oscillation, or ENSO. During El Ni\u00f1o events, weak trade winds are associated with above-average surface temperatures in those waters.<\/p>\n<p class=\"uiTextSmall f aic jcc\">Article continues below this ad<\/p>\n<p>In the past, warmer waters off California originated with El Ni\u00f1o, but this current heat wave formed for different reasons. For Rudnick, weaker winds, slowing down the upwelling of deep-sea cold waters, was one possibility, but he said he was still studying some additional explanations.\u00a0<\/p>\n<p>\u201cSo far, this has not actually related to El\u00a0Ni\u00f1o,\u201d Swain agreed. \u201cThis is something else. But the developing El Ni\u00f1o event might actually amplify it, causing this marine heat wave to last longer and become even stronger than it otherwise might have been.\u201d\u00a0\u00a0<\/p>\n<p>El Ni\u00f1o patterns tip the odds in favor of a wetter winter, especially in Southern California, but it\u2019s not completely predictable. The marine heat wave alone is expected to impact the weather in myriad ways, such as\u00a0<a href=\"https:\/\/www.latimes.com\/environment\/story\/2026-04-16\/ocean-california-sst-enso-blob-marine-warming\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">bringing<\/a> humidity, driving away fog and even <a href=\"https:\/\/www.sfchronicle.com\/weather\/article\/pacific-ocean-california-weather-22206814.php\" data-link=\"native\" class=\"\" rel=\"nofollow noopener\" target=\"_blank\">affecting<\/a> Pacific hurricane season.\u00a0<\/p>\n<p>And how long will it last? A heat wave in the air can snap back to cooler temperatures in just a few hours, but when a vast volume of water is involved, ocean heat grows and dissipates more slowly.\u00a0<\/p>\n<p class=\"uiTextSmall f aic jcc\">Article continues below this ad<\/p>\n<p>\u201cWhen there\u2019s this much warm water, it\u2019s just not going to disappear overnight,\u201d\u00a0Rudnick, who runs the glider program for Scripps, said. \u201cHeck no. It took months to get this way, and it\u2019s going to take months to go away, too.\u201d<\/p>\n<p>Swain emphasized that this all folds into a bigger narrative about climate change. Sometimes natural cycles can compound human-caused warming and other times they counteract it, he explained. In recent years, the coast has been cooler than average, soothing the warming ocean.\u00a0<\/p>\n<p>\u201cThe oceans are getting warmer because of human-caused warming and accumulation of heat-trapping gasses in the atmosphere,\u201d Swain said. He added: \u201cNatural cycles, natural variability, is now going to be in alignment, at least this summer, with the long-term warming trend. And boy howdy, does it look like it\u2019s going to be a persistent and extreme marine heat wave.\u201d<\/p>\n<p class=\"uiTextSmall f aic jcc\">Article continues below this ad<\/p>\n","protected":false},"excerpt":{"rendered":"A sunset crests over the Scripps Pier in La Jolla. Erik Jepsen Hottest. Earliest. Most extreme. California\u2019s meteorologists&hellip;\n","protected":false},"author":2,"featured_media":278427,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[7,9,8,1692,106624,1691],"class_list":{"0":"post-278426","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-california","8":"tag-california","9":"tag-california-headlines","10":"tag-california-news","11":"tag-sfgnews","12":"tag-sfgscience","13":"tag-sfgweather"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/posts\/278426","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/comments?post=278426"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/posts\/278426\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/media\/278427"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/media?parent=278426"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/categories?post=278426"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/tags?post=278426"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}