ICES Working Group on Oceanic Hydrography (WGOH) is the custodian of some of the longest-running time-series of ocean observations, many of which now extend more than forty years.
The group meets annually to review the oceanographic conditions in the North Atlantic, publishing the findings in
ICES Report on Ocean Climate. After meeting in April, their joint analysis has strengthened individual organizational efforts to provide the following highlights for the North Atlantic in 2021.
Salinity
The record low salinities that were first observed in the subpolar gyre between 2016–2017 have continued to spread out -within expected timelines- along the main circulation pathways, both northwards into the North Sea, Nordic Seas, Barents Sea, and Fram Strait and southwards into the subtropical gyre.
Low salinity anomalies are now also apparent deeper in the water column, meaning that this is no longer an exclusive surface feature.
Salinities in the subpolar gyre itself and the immediate downstream pathways, for example Atlantic Water in the Faroe Current, Faroe Bank Channel, and deep regions west of Scotland, have increased to near average.
Record low salinity in the surface waters of the Bay of Biscay and Iberian coast, the Gulf of Cadiz, and the Canaries is
changing water column stratification (i.e. increasing the buoyancy anomaly). For example, in the Bay of Biscay and Iberian coast, the salinity of the upper 500 m is the lowest observed in approximately the last three decades.
Temperatures
Temperatures across the North Atlantic surface water and the inflowing Atlantic Water to the Norwegian Sea and the Barents Sea remain close to the long-term average. However, the deep waters in the Nordic Seas and associated overflow branches have continued to warm. In some regions, for example, the Greenland Sea between 700–2000 m, this
warming appears to have slowed or even stopped.
Record warming was observed on the continental shelves of the western North Atlantic in 2021.
Near-bed ocean
temperatures were substantially above normal across the region, including record highs in the northern Gulf of
St. Lawrence, off southern Newfoundland, and across the Northeast US Shelf. The area of sea ice in the Barents Sea was much lower in 2021 compared to previous years. The lowest ever volume of sea ice was recorded in the Gulf of St. Lawrence since records began in 1969.
WGOG chairs Caroline Cusack and Tycjan Wodzinowski paid special thanks to the experts that maintain the time series. “The contribution of each WGOH member is integral to informing the wider community on the ocean climate status of the North Atlantic each year. We are very grateful to everyone who contributes to ICES Report on Ocean Climate. We are particularly grateful for their continued involvement and support and for their resilience when faced with challenges such as the Covid-19 outbreak that hindered recent activities when for example in 2021, government restrictions prevented data collection at some locations."
ICES 4th Decadal Variability of the North Atlantic and its Marine Ecosystems: 2010–2019
The ICES/NAFO/IMR 4th Symposium on “Decadal Variability of the North Atlantic and its Marine Ecosystems: 2010 – 2019 takes place later this month, 20–22 June, in Bergen, and will gather researchers to review the variability of North Atlantic environmental conditions and marine ecosystems over the past decade. This symposium will be the fourth in this series, all of which have been organized by WGOH since the first event in 1991.
The intention is to understand the relationship between ecosystem components and how they influence the distribution, abundance and productivity of living marine resources. While the symposium focuses on reviewing the last decade, contributions related to sub-decadal forecast of ecosystem change and application of environmental data to ocean resource management are also welcome.
ICES Working Group on Oceanic Hydrography (WGOH) closely monitors the ocean conditions in ICES area by updating and reviewing results from standard hydrographic sections and stations. WGOH's work addresses Ecosystem science, Ecosystem science, Observation and exploration, and Conservation and management science, three of ICES scientific priorities.
Discover all seven interrelated scientific priorities and how our network will address them in our Science Plan: “Marine ecosystem and sustainability science for the 2020s and beyond".
