This dataset provides projected sea surface temperature and salinity as well as projected ocean bottom temperature and salinity in the Northwest Atlantic under a high emission scenario Representative Concentration Pathway (RCP) 8.5. The results are generated by a North Atlantic Ocean-ice Downsling System (NAODS) that downscales the global Climate Change System Model Version 4 (CCSM4) output. NAODS couples 1/12-degree model for the northwest Atlantic with a 1/4-degree model for the North Atlantic (Han et al., 2025). Bi-decadal means are included for 1986-2005, 2006-2025, 2026-2045, 2046-2065, 2066-2085, and 2080-2099, respectively.

This dataset provides projected sea surface temperature and salinity as well as projected ocean bottom temperature and salinity in the Northwest Atlantic under an intermediate emission scenario Representative Concentration Pathway (RCP) 4.5. The results are generated by a North Atlantic Ocean-ice Downscaling System (NAODS) that downscales the global Hedley Centre Global Environmental Model Version 2 with an Earth System component (HadGEM2-ES) output. NAODS couples a 1/12 ^o model for the northwest Atlantic with a 1/4 ^o model for the North Atlantic (Han et al., 2025). Bi-decadal means are included for 1986-2005, 2006-2025, 2026-2045, 2046-2065, 2066-2085, and 2080-2099, respectively.

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 Ocean Data Inventory database is an inventory of all of the oceanographic time series data held by the Ocean Science Division at the Bedford Institute of Oceanography. The data archive includes about 5800 current meter and acoustic doppler time series, 4500 coastal temperature time series from thermographs, as well as a small number (200) of tide gauges. Many of the current meters also have temperature and salinity sensors. The area for which there are data is roughly defined as the North Atlantic and Arctic from 30° - 82° N, although there are some minor amounts of data from other parts of the world. The time period is from 1960 to present. The database is updated on a regular basis.

The Department of Fisheries established a survey of demersal juvenile Atlantic cod (*Gadus morhua*) in the nearshore (<10 m deep) in 1959. This survey aimed to characterize the distribution and abundance of juvenile Atlantic cod and was based upon Norway's Flodevigen sampling program which has been conducted continuously since 1919. A 25 m seine was used to sample juvenile Atlantic cod nursery locations on the Avalon Peninsula and Northeast coast of the island of Newfoundland in September and October. The survey continued until 1964 and became known as the Fleming survey, after original initiator Alistair Fleming. The survey was reinstated by Memorial University of Newfoundland from 1992 to 1997. Multiple tows were conducted at a subset of the original 55 Fleming sites located in St. Mary's Bay, Trepassey Bay, the Southern Shore, Conception Bay, Trinity Bay, Bonavista Bay, Gander Bay, New World Island, Fortune Harbour, Badger Bay, Halls Bay and Green Bay.This data set includes several different subsets, some of which span both Fleming Survey periods (1959-1964 and 1992-1997):I. JuvCodCatch60s90s:Catches of juvenile Atlantic cod (1959-1964, 1992-1997) from the first two consecutive tows at each site. This is a summary based on JuvCodLengths90s and FlemingSurveyData60s;II. JuvCodLength90s:Lengths of all individual juvenile Atlantic cod caught for each site (1992-1997);III. SiteEnvData60s90s:Station data for Fleming data 1992-1997;IV. FlemingSurveyData60s:Fleming survey data from 1959-1964 (note there are three record types pertaining to: station data "type 1"; general species catch data including juvenile Atlantic cod grouped by age class ("1+", "Zeroes", and "Total") "type 2; and juvenile Atlantic cod (species 223) listed in length bins "type 3"; andV. FlemingBycatch60s92to96:Bycatch data from 1959-1964 & 1992-1996 from first two tows at each site. This is a summary based partly on the FlemingSurveyData60s set.

Effective conservation planning relies on understanding population connectivity which can be informed by genomic data. This is particularly important for sessile species like the horse mussel (Modiolus modiolus), a key habitat-forming species and conservation priority in Atlantic Canada), yet little genomic information is available to describe horse mussel connectivity patterns. We used more than 8000 restriction-site associated DNA sequencing-derived single nucleotide polymorphisms and a panel of 8 microsatellites to examine genomic connectivity among horse mussel populations in the Bay of Fundy, along the Scotian Shelf, and in the broader northwestern Atlantic extending to Newfoundland. Despite phenotypic differences between sampling locations, we found an overall lack of genetic diversity and population structure in horse mussels in the Northwest Atlantic Ocean. All sampled locations had low heterozygosity, very low FST, elevated inbreeding coefficients, and deviated from Hardy-Weinberg Equilibrium, highlighting generally low genetic diversity across all metrics. Principal components analysis, Admixture analysis, pairwise FST calculations, and analysis of outlier loci (potentially under selection) all showed no independent genomic clusters within the data, and an analysis of molecular variance showed that less than 1% of the variation within the SNP dataset was found between sampling locations. Our results suggest that connectivity is high among horse mussel populations in the Northwest Atlantic, and coupled with large effective population sizes, this has resulted in minimal genomic divergence across the region. These results can inform conservation design considerations in the Bay of Fundy and support further integration into the broader regional conservation network.Cite this data as: Van Wyngaarden, Mallory et al. (2024). Widespread genetic similarity between Northwest Atlantic populations of the horse mussel, Modiolus modiolus. Published: May 2025. Coastal Ecosystem Science Division, Maritimes Region, Fisheries and Oceans Canada, Dartmouth, NS.

Monthly mean salinity from Bedford Institute of Oceanography North Atlantic Model (BNAM) results were averaged over 1990 to 2015 period to create monthly mean climatology for the Northwest Atlantic Ocean, which can be considered as a representation of the climatological state of the Northwest Atlantic Ocean. The BNAM model is eddy-resolving, NEMO-based ice-ocean coupled North Atlantic Ocean model developed at the Bedford Institute of Oceanography (BIO) to support DFO monitoring programs. The data available here is monthly climatology for eight selected depths (surface, 110 m, 156 m, 222 m, 318 m, 541 m, 1062 m, bottom) in 1/12 degree spatial resolution. The data for each month from 1990 until present for the entire model domain ( 8°–75°N latitude and 100°W–30°E longitude) and various depths is available upon request.The 1990-2017 model hindcast result is compared with observational data from surface drifter and satellite altimetry. The model demonstrates good skill in simulating surface currents, winter convection events in the Labrador Sea, and the Atlantic Meridional Overturning Circulation as observed at 26.5°N and 41°N. Model results have been used to interpret changes in the Labrador Current and observed warming events on the Scotian Shelf, and are reported through the annual AZMP Canadian Science Advisory Secretariat Process.When using data please cite following:Wang, Z., Lu, Y., Greenan, B., Brickman, D., and DeTracey, B., 2018. BNAM: An eddy resolving North Atlantic Ocean model to support ocean monitoring. Can. Tech. Rep. Hydrogr. Ocean. Sci. 327: vii + 18p

Monthly mean currents from Bedford Institute of Oceanography North Atlantic Model (BNAM) results were averaged over 1990 to 2015 period to create monthly mean climatology for the Northwest Atlantic Ocean, which can be considered as a representation of the climatological state of the Northwest Atlantic Ocean. The BNAM model is eddy-resolving, NEMO-based ice-ocean coupled North Atlantic Ocean model developed at the Bedford Institute of Oceanography (BIO) to support DFO monitoring programs. The data available here is monthly climatology for eight selected depths (surface, 110 m, 156 m, 222 m, 318 m, 541 m, 1062 m, bottom) in 1/12 degree spatial resolution. The data for each month from 1990 until present for the entire model domain ( 8°–75°N latitude and 100°W–30°E longitude) and various depths is available upon request.The 1990-2017 model hindcast result is compared with observational data from surface drifter and satellite altimetry. The model demonstrates good skill in simulating surface currents, winter convection events in the Labrador Sea, and the Atlantic Meridional Overturning Circulation as observed at 26.5°N and 41°N. Model results have been used to interpret changes in the Labrador Current and observed warming events on the Scotian Shelf, and are reported through the annual AZMP Canadian Science Advisory Secretariat Process.When using data please cite following:Wang, Z., Lu, Y., Greenan, B., Brickman, D., and DeTracey, B., 2018. BNAM: An eddy resolving North Atlantic Ocean model to support ocean monitoring. Can. Tech. Rep. Hydrogr. Ocean. Sci. 327: vii + 18p

This project was completed by the Salmonids Section in the Newfoundland and Labrador Science Branch of Fisheries and Oceans Canada (DFO). The Coastal Environmental Baseline Program has supported efforts in 2018 and 2019 of tagged Atlantic salmon smolts leaving the Bay de L’eau River and Rushoon River region of Placentia Bay. This was part of a larger four year tracking study in this region (2018, 2019, 2021, 2022) trying to improve DFO’s understanding of the residency, survival, and migration routes of Atlantic salmon smolts during the first months at sea within northwest Placentia Bay. As of spring 2023, four years of detection data were being processed with the goal of presenting this work at the next Atlantic salmon CSAS meeting and developing a primary publication. This record contains the locations there smolt were tagged in Placentia Bay, NL.

Monthly mean temperature from Bedford Institute of Oceanography North Atlantic Model (BNAM) results were averaged over 1990 to 2015 period to create monthly mean climatology for the Northwest Atlantic Ocean, which can be considered as a representation of the climatological state of the Northwest Atlantic Ocean. The BNAM model is eddy-resolving, NEMO-based ice-ocean coupled North Atlantic Ocean model developed at the Bedford Institute of Oceanography (BIO) to support DFO monitoring programs. The data available here is monthly climatology for eight selected depths (surface, 110 m, 156 m, 222 m, 318 m, 541 m, 1062 m, bottom) in 1/12 degree spatial resolution. The data for each month from 1990 until present for the entire model domain ( 8°–75°N latitude and 100°W–30°E longitude) and various depths is available upon request.The 1990-2017 model hindcast result is compared with observational data from surface drifter and satellite altimetry. The model demonstrates good skill in simulating surface currents, winter convection events in the Labrador Sea, and the Atlantic Meridional Overturning Circulation as observed at 26.5°N and 41°N. Model results have been used to interpret changes in the Labrador Current and observed warming events on the Scotian Shelf, and are reported through the annual AZMP Canadian Science Advisory Secretariat Process.When using data please cite following:Wang, Z., Lu, Y., Greenan, B., Brickman, D., and DeTracey, B., 2018. BNAM: An eddy resolving North Atlantic Ocean model to support ocean monitoring. Can. Tech. Rep. Hydrogr. Ocean. Sci. 327: vii + 18p