2014–16 North Pacific marine heatwave

2014–16 North Pacific marine heatwave
Name	2014–16 North Pacific marine heatwave
Location	North Pacific Ocean
Date	2014–2016
Type	marine heatwave

2014–16 North Pacific marine heatwave was an extensive anomalous warming of the northeastern Pacific Ocean between 2014 and 2016 that altered oceanographic conditions along the Gulf of Alaska, Bering Sea, and the West Coast of the United States and Canada. The event coincided with exceptional shifts in atmospheric circulation associated with the Pacific Decadal Oscillation, El Niño–Southern Oscillation, and a powerful North Pacific High. Observations were made by agencies including the National Oceanic and Atmospheric Administration, the Canadian Centre for Climate Modelling and Analysis, and research programs associated with the Scripps Institution of Oceanography.

Overview

The anomaly, often studied through satellite-derived sea surface temperature products from NOAA and in situ data from the Argo program, produced surface temperature departures that persisted for multiple years across the Northeast Pacific. It was contemporaneous with the 2015–16 El Niño, influenced fisheries managed by the Alaska Department of Fish and Game and the Pacific Fishery Management Council, and drew involvement from research institutions such as the Woods Hole Oceanographic Institution and the University of Washington.

Causes and development

Researchers attributed the warming to a combination of large-scale climate modes and regional atmospheric forcing. Positive phases of the Pacific Decadal Oscillation and protracted patterns in the North Pacific High reduced heat loss via weakened surface winds and suppressed upwelling along the California Current System. Teleconnections from the El Niño–Southern Oscillation and an anomalous ridge linked to the Arctic Oscillation amplified sea level pressure gradients over the North Pacific Ocean. Studies by teams at NOAA Pacific Marine Environmental Laboratory and the National Centre for Atmospheric Research analyzed how advection, reduced latent heat flux, and altered mixed-layer dynamics initiated and sustained the event.

Physical characteristics

The heatwave produced sea surface temperatures several degrees Celsius above climatology in sectors of the Gulf of Alaska and along the West Coast of North America. Satellite products from MODIS, AVHRR and ocean reanalysis from the Global Ocean Data Assimilation System documented anomalies in surface temperature, sea level height, and upper-ocean stratification. Subsurface observations from Argo floats and research cruises measured shoaling of the mixed layer, altered thermocline structure, and expansion of the subtropical gyre influence. The event also affected sea ice extent in the Bering Sea and contributed to a regional sea level rise tied to thermal expansion and wind-driven redistribution.

Ecological and economic impacts

The warming coincided with ecological disruptions across pelagic and benthic systems. Shifts in the distributions of Pacific salmon, alewife, Pacific cod, and walleye pollock were reported by the Alaska Fisheries Science Center and the Fisheries and Oceans Canada. Harmful algal blooms involving genera like Pseudo-nitzschia were more frequent, impacting shellfish harvests and prompting closures by agencies such as the National Marine Fisheries Service and provincial regulators. Marine mammal strandings and atypical sightings involved species monitored by the Marine Mammal Center and the U.S. Fish and Wildlife Service. Economic effects included disrupted fisheries managed under the North Pacific Fishery Management Council and revenue losses documented by regional fisheries associations and coastal communities from British Columbia to California.

Monitoring and research

Observational campaigns by the Scripps Institution of Oceanography, Woods Hole Oceanographic Institution, University of Alaska Fairbanks, and international partners expanded time-series measurements from coastal stations, research vessels, and autonomous platforms. Analytical work appeared in journals and was supported by programs within NOAA, the National Science Foundation, and the Canadian Space Agency. Modeling efforts employed coupled climate models from the Coupled Model Intercomparison Project ensembles and regional ocean models run at institutions such as the Geophysical Fluid Dynamics Laboratory to attribute roles of internal variability versus external forcing.

Responses and management

Resource managers at the Pacific Fishery Management Council, North Pacific Fishery Management Council, and provincial agencies implemented adaptive measures including quota adjustments, spatial closures, and enhanced monitoring of harmful algal blooms coordinated with the Integrated Ocean Observing System. Conservation groups and indigenous organizations including the Aleutian Pribilof Islands Association and tribal fisheries programs engaged in co-management and community-based monitoring. Policy discussions at venues involving the United Nations's climate science stakeholders and interagency task forces sought to integrate heatwave preparedness into marine resource management frameworks.

Legacy and long-term trends

The event became a focal case for studying compound climate extremes, influencing subsequent research on marine heatwaves in the context of anthropogenic warming assessed by the Intergovernmental Panel on Climate Change. It informed improvements to operational forecasts produced by NOAA Climate Prediction Center and advances in ecosystem-based management promoted by agencies such as the National Oceanic and Atmospheric Administration and the North Pacific Research Board. Ongoing monitoring by universities and agencies including the University of Washington and the Alaska Marine Science–NOAA partnership tracks how decadal variability like the Pacific Decadal Oscillation and secular warming will modulate the frequency and intensity of future ocean heatwaves.

Category:Marine heat waves Category:Pacific Ocean