Blob (ocean heat wave)

Contents

Blob (ocean heat wave)

The Blob was a large, persistent marine heatwave in the northeast Pacific Ocean notable for unusually warm sea surface temperatures that affected marine ecosystems, fisheries, and weather patterns. It drew attention from scientists at institutions such as National Oceanic and Atmospheric Administration, Scripps Institution of Oceanography, University of Washington, University of California, Santa Cruz, and Institute of Ocean Sciences and prompted interdisciplinary study involving agencies like National Aeronautics and Space Administration and Pew Charitable Trusts.

Overview and Definition

Formation hypotheses involved persistent atmospheric ridging over the northeast Pacific linked to features studied by teams at Oregon State University, Stanford University, University of California, Los Angeles, Harvard University, and Massachusetts Institute of Technology. Mechanisms included reduced surface heat loss associated with altered storm tracks examined by European Centre for Medium-Range Weather Forecasts, suppressed wind-driven mixing described by Scripps Institution of Oceanography and NOAA, and advection of warm water connected to currents like the California Current and influences studied by Monterey Bay Aquarium Research Institute. Interactions with phenomena investigated by El Niño–Southern Oscillation, Pacific Decadal Oscillation, North Pacific Gyre, and datasets from Argo program, TAO/TRITON array, NOAA buoys, and sea surface temperature satellite missions were central to mechanistic explanations pursued by Lamont–Doherty Earth Observatory and University of Miami Rosenstiel School.

The most prominent occurrence spanned roughly 2013–2016, documented by researchers at NOAA Pacific Marine Environmental Laboratory, Scripps Institution of Oceanography, University of Washington, Arizona State University, and University of California, Santa Barbara. Earlier and later regional marine heatwaves were compared using records from Historical climatology networks, Paleoceanography, National Snow and Ice Data Center, International Arctic Research Center, and archives curated by Smithsonian Institution. Chronologies incorporated observations from Canadian Ice Service, Fisheries and Oceans Canada, Alaska Fisheries Science Center, Monterey Bay Aquarium》, and monitoring programs supported by North Pacific Anadromous Fish Commission. Scientists from NOAA Fisheries and Pacific States Marine Fisheries Commission documented biological responses through multi-year timelines.

Ecological impacts included shifts in distributions of species monitored by Alaska Sea Grant, California Department of Fish and Wildlife, Washington Department of Fish and Wildlife, Oregon Department of Fish and Wildlife, and researchers at Hakai Institute. Notable effects involved northward range shifts of taxa studied by University of British Columbia, population declines recorded by NOAA Fisheries and Atlantic Salmon Federation analogs, harmful algal blooms tracked by Monterey Bay Aquarium Research Institute and Vancouver Aquarium, and seabird die-offs investigated by Cornell Lab of Ornithology and Audubon Society. Commercial impacts affected fisheries associated with Pacific Halibut Commission, International Pacific Halibut Commission, Alaska Fisheries Science Center, Parks Canada marine areas, and seafood supply chains connected to National Fisheries Institute and Seafood Watch. Tourism and coastal economies monitored by Economic Development Agency of Canada and municipal authorities in British Columbia and Washington (state) also experienced consequences.

Observation networks contributing data included the Argo program, Jason satellite series, MODIS, AVHRR, GRACE mission, and in situ arrays maintained by NOAA buoys, Canadian Marine Environmental Data Service, Scripps Institution of Oceanography moorings, and University of Washington sensors. Modeling efforts used frameworks from Community Earth System Model, NOAA Geophysical Fluid Dynamics Laboratory, European Centre for Medium-Range Weather Forecasts, NCAR Community Atmosphere Model, and operational systems at Naval Research Laboratory. Data assimilation and forecasting drew on techniques developed at Jet Propulsion Laboratory, Princeton University, Columbia University Lamont–Doherty, and GEOMAR Helmholtz Centre for Ocean Research Kiel.