Description: Seasonal climatologies for salinity of the Northeast Pacific Ocean were computed to cover the period 2001 to 2020. Historibal observations included all available conductivity-temperature_depth (CTD), bottle and profiling floats in the NODC World Ocean Database, Marine Environmental Data Services (MEDS), Institute of Ocean Sciences Water Properties website and the Canadian Integrated Ocean Observing System (CIOOS Pacific). Methods: Interpolation was carried out in up to fifty-two vertical levels from surface to 5000m. Data-Interpolating Variational Analysis (DIVA) was used for spatial interpolation for all years within each season and estimates projected onto a consistent grid. The average of the grid nodes was calculated to obtain the seasonal climatology. DIVA was used again on the final climatology followed by a median filter and a 5-point smoother. Spring months were defined as April to June, summer months were defined as July to September, fall months were defined as October to December, and winter months were defined as January to March. The data available here contain raster layers of seasonal salinity climatology for the Canadian Pacific Exclusive Economic Zone (EEZ), a subset of seasonal climatology of the Northeast Pacific Ocean, with high spatial resolution of 1/300 degree. Data Sources: NODC, MEDS, IOS and CIOOS Pacific Data. Uncertainties: Uncertainties are introduced when quality controlled observational data are spatially interpolated to varying distances from the observation point. Climatological averages are calculated from these interpolated values.

Plankton (zooplankton and large phytoplankton) are collected using the Continuous Plankton Recorder (CPR) in the Northwest (NW) Atlantic along tracks transited by container ships from Reykjavik (Iceland) to St. John’s, NL (the Z line), and between St. John’s and the New England Coast, along the Scotian Shelf (the E and MD lines). The CPR Survey is the longest running, most geographically extensive marine ecological survey in the world, providing comparable data on the geographical distribution, seasonal cycles and year-to-year changes in abundance of plankton over a large spatial area. The first northwest Atlantic samples were collected in the Irminger Sea in 1957, and sampling was extended farther west to the Scotian Shelf a few years later. Sampling has continued to the present with some interruptions during the late 1970s and 1980s. Sampling is nominally once per month along the E, MD, and Z lines. DFO Sample collection and analysis are led by the Continuous Plankton Recorder Survey program at the Marine Biological Association of the UK. DFO provides partial support for the northwest Atlantic survey carried out on the E, MD, and Z lines and incorporates CPR data in Atlantic Zone Monitoring Program ocean environmental status reporting.

The hydrographic 1991 to 2020 climatology for the Maritimes region Atlantic Zone Monitoring Program core transects, Cabot Strait, Louisbourg, Halifax, Browns Bank, and Northeast Channel, are calculated to support annual reporting on seasonal variability. Details on data coverage for these transects and ancillary transects occupied since the inception of the program are provided. Comparisons with the previous climatology period, years 1981 to 2010, are summarized when possible. Cite this data as: Layton, C. Data of: Maritimes Region Atlantic Zone Monitoring Program 1991 to 2020 Hydrographic Transect Climatology. Published: August 2025. Ocean Ecosystems Science Division, Fisheries and Oceans Canada, Dartmouth, N.S. https://open.canada.ca/data/en/dataset/5f9c5d65-3ce1-4bdd-8b43-34086620d1e3

The Fisheries and Oceans Canada ecosystem surveys are conducted annually and are a source of integrated ecosystem monitoring data. These survey data are the primary data source for monitoring trends in species distribution, abundance, and biological condition within the region, and also provide data to the Atlantic Zonal Monitoring Program (AZMP) for monitoring hydrographic conditions, along with zooplankton and phytoplankton. The surveys follow a stratified random sampling design, and include sampling using a bottom otter trawl, CTD rosette and vertical plankton tows. Data from the bottom trawl catch are used to monitor the distribution and abundance of fish and invertebrates throughout the Scotian Shelf, Bay of Fundy and Georges Bank. Cite this data as: Clark, D., Emberley, J. Data of MARITIMES RESEARCH VESSEL SURVEYS. Published January 2021. Population Ecology Division, Fisheries and Oceans Canada, Dartmouth, N.S. https://open.canada.ca/data/en/dataset/8ddcaeea-b806-4958-a79f-ba9ab645f53b