Blob (Pacific Ocean)

Blob (Pacific Ocean)
Name	Blob (Pacific Ocean)
Type	Marine heat anomaly
Location	North Pacific Ocean
Discovered	2013
Duration	2013–2016 (major episode); recurring events
Area	Variable (hundreds of thousands of km²)
Temperature anomaly	Up to +3–5 °C above average

Blob (Pacific Ocean)

The Blob was a large, persistent marine heat anomaly in the North Pacific Ocean that emerged in 2013 and drew international attention for its scale, duration, and ecological consequences. It altered physical oceanography, influenced atmospheric patterns across the Pacific Rim, and affected fisheries, marine mammals, seabirds, and coastal communities from Alaska to California. The event spurred interdisciplinary research involving climate science, oceanography, fisheries science, and conservation.

Overview

The anomaly was first identified by researchers associated with National Oceanic and Atmospheric Administration, University of Washington, and Scripps Institution of Oceanography, and was subsequently documented by agencies such as Environment and Climate Change Canada and institutions including Alaska Fisheries Science Center, NOAA Pacific Marine Environmental Laboratory, North Pacific Marine Science Organization, and PICES. Media coverage by outlets like The New York Times, National Geographic, BBC, Scientific American, and Nature amplified scientific and public awareness. The phenomenon intersected with broader climate events such as El Niño–Southern Oscillation, the Pacific Decadal Oscillation, and discussions within Intergovernmental Panel on Climate Change assessments.

Formation and Causes

Research attributed formation to a combination of anomalous atmospheric forcing and oceanographic conditions. Strong high-pressure ridging associated with the North Pacific High and persistent blocking patterns linked to the Arctic Oscillation and Pacific North American pattern reduced surface winds, weakened Ekman transport and diminished mixing processes described in studies at Scripps Institution of Oceanography and Woods Hole Oceanographic Institution. Reduced heat loss from the ocean to the atmosphere, along with advection from subtropical gyre regions managed by the North Pacific Gyre, allowed sea surface temperatures to rise. Analyses published by teams at NOAA and University of Victoria invoked teleconnections involving Madden–Julian Oscillation, interactions with the Aleutian Low, and contributions from long-term trends reported in IPCC assessments.

Physical Characteristics and Extent

The Blob was characterized by positive sea surface temperature anomalies detected by satellite sensors operated by NASA platforms like Aqua and Terra, and by in situ measurements from the Argo float array, NOAA buoys, and research cruises conducted by institutions such as University of Alaska Fairbanks and Monterey Bay Aquarium Research Institute. Anomalies reached up to +3–5 °C above climatology across hundreds of thousands of square kilometers, extending from the Gulf of Alaska southward toward the California Current System and eastward toward the Gulf of AlaskaAleutian Islands. Depth structure analyses from ROV surveys and oceanographic moorings showed heat penetrating the upper mixed layer and affecting thermocline dynamics described in publications by Scripps Institution of Oceanography and Lamont–Doherty Earth Observatory.

Ecological and Economic Impacts

The Blob disrupted trophic dynamics within ecosystems managed by agencies like the Alaska Department of Fish and Game, California Department of Fish and Wildlife, and Fisheries and Oceans Canada. Warm-water species such as Pacific sardine, market squid, and southern rockfish shifted ranges, while cold-adapted species including Pacific cod, walleye pollock, and eulachon experienced reduced recruitment. Harmful algal blooms linked to warm conditions resulted in domoic acid accumulation monitored by NOAA Fisheries and led to closures affecting fisheries for Dungeness crab, shellfish and other commercial stocks managed under frameworks like the Magnuson–Stevens Fishery Conservation and Management Act. Marine mammals including Steller sea lion, California sea lion, and sea otter faced prey shortages, and seabird die-offs affected species such as Cassin's auklet and common murre, with wildlife responses coordinated by organizations like U.S. Fish and Wildlife Service and Canadian Wildlife Service. Economic impacts were recorded in ports from Anchorage to San Francisco, affecting processors, fishing communities, and tourism sectors represented by regional bodies and unions.

Detection, Monitoring, and Research

Detection relied on multisensor remote sensing by NOAA, NASA, and international programs including Copernicus Programme and data assimilation systems at ECMWF used by centers like Joint Institute for the Study of the Atmosphere and Ocean. Continuous observations from Argo, satellite altimetry from missions such as Jason-2 and Jason-3, and ocean color sensors helped map anomalies. Research collaborations involved universities including University of Washington, Oregon State University, University of British Columbia, University of California, Santa Cruz, and laboratories like Pacific Marine Environmental Laboratory. Peer-reviewed analyses appeared in journals such as Geophysical Research Letters, Science, Nature Communications, Proceedings of the National Academy of Sciences, and Journal of Climate. Community science and monitoring programs run by organizations like NOAA Fisheries and regional councils augmented dataset coverage.

Response and Mitigation Efforts

Management responses encompassed adaptive fisheries closures and quota adjustments administered by councils like the North Pacific Fishery Management Council and the Pacific Fishery Management Council, public health advisories from Centers for Disease Control and Prevention and regional agencies, and conservation measures by entities such as The Nature Conservancy and World Wildlife Fund. Research-driven mitigation strategies emphasized improved monitoring networks supported by National Science Foundation grants, ecosystem-based management approaches promoted at forums like Western and Central Pacific Fisheries Commission and regional workshops convened by PICES, and integration of climate projections from IPCC scenarios into resource planning by state and provincial authorities. Long-term resilience efforts included habitat restoration projects coordinated with NOAA Restoration Center and community adaptation funding administered by agencies including U.S. Department of Commerce and provincial counterparts.

Category:Oceanography Category:Climate events Category:Marine ecology