Patterns of wet deposition of the nitrate (NO3), non-sea-salt sulfate (xSO4) and ammonium (NH4) ions across areas of Canada and the United States are based on measurements of precipitation depth and ion concentrations in precipitation samples. xSO4 refers to the wet deposition of sulfate with the sea-salt sulfate contribution removed at coastal sites. These measurements were collected and quality controlled by their respective networks: in Canada, the federal Canadian Air and Precipitation Monitoring Network (CAPMoN) and provincial or territorial networks in Alberta, New Brunswick, the Northwest Territories, Nova Scotia, Ontario and Quebec. In the United States, wet deposition measurements were made by two coordinated networks: the National Atmospheric Deposition Program (NADP) / National Trends Network (NTN) and the NADP/Atmospheric Integrated Research Monitoring Network (AIRMoN). Only data from sites that were designated as regionally representative were used in the mapping. Wet deposition amounts were interpolated by ordinary kriging using ArcMap Geostatistical Analyst. The map is limited to the contiguous U.S. and southeastern or southern Canada because outside that region, the interpolation error exceeds 30% due to the larger distances between stations. Links to annual and five-year average maps are available in the associated resources.

Annual and five-year (5YA) average wet deposition maps for the ammonium ion are available. The file formats include geodatabase files (*.gdb) compatible with geospatial software (e.g. ESRI ArcGIS) and KMZ files compatible with virtual globe software (e.g. Google Earth™). Maps can also be viewed online via Open Maps and the ArcGIS online viewer. Annual deposition from each site was screened for completeness using the following criteria: (1) precipitation amounts were recorded for >90% of the year and >60% of each quarter, and (2) ammonium concentrations were reported for >70% of the precipitation measured over the year and for >60% of each quarter. Five-year average wet deposition values are averaged annual deposition values with a completeness criterion >60% for the five-year period. Units for wet deposition fluxes are in kg of NH4 per hectare per year (kg ha-1 y-1). Sources of measurement data and spatial interpolation method are described here: https://doi.org/10.18164/e8896575-1fb8-4e53-8acd-8579c3c055c2. Recommended citation: Environment and Climate Change Canada, [year published]. NH4 Wet Deposition Maps. Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada. [URL/DOI], accessed [date].Recommended acknowledgement: The author(s) acknowledge Environment and Climate Change Canada for the provision of Canada-U.S. wet deposition kriging maps accessed from the Government of Canada Open Government Portal at open.canada.ca, and the data providers referenced therein.

Air emissions from oil sands development can come from a number of sources including industrial smokestacks, tailings ponds, transportation, and dust from mining operations. Air quality monitoring under the Joint Canada-Alberta Implementation Plan for the Oil Sands is designed to determine the contribution of emissions from oil sands activities to local and regional air quality and atmospheric deposition both now and in the future. Deposition data include: - Passive Sampling of PACs deployed for two month periods across a network of 17 sites - Active sampling of PACs at three sites to inform the amount of dry deposition - Particulate metals (24 hour integrated samples following the one in six day National Air Pollution Surveillance (NAPS) cycle)

Annual and five-year (5YA) average wet deposition maps for the non-sea-salt sulfate ion are available. The file formats include geodatabase files (*.gdb) compatible with geospatial software (e.g. ESRI ArcGIS) and KMZ files compatible with virtual globe software (e.g. Google Earth™). Maps can also be viewed online via Open Maps and the ArcGIS online viewer. Annual deposition from each site was screened for completeness using the following criteria: (1) precipitation amounts were recorded for >90% of the year and >60% of each quarter, and (2) sulfate concentrations were reported for >70% of the precipitation measured over the year and for >60% of each quarter. Five-year average wet deposition values are averaged annual deposition values with a completeness criterion >60% for the five-year period. Units for wet deposition fluxes are in kg of xSO4 per hectare per year (kg ha-1 y-1). Sources of measurement data and spatial interpolation method are described here: https://doi.org/10.18164/e8896575-1fb8-4e53-8acd-8579c3c055c2. Recommended citation: Environment and Climate Change Canada, [year published]. xSO4 Wet Deposition Maps. Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada. [URL/DOI], accessed [date].Recommended acknowledgement: The author(s) acknowledge Environment and Climate Change Canada for the provision of Canada-U.S. wet deposition kriging maps accessed from the Government of Canada Open Government Portal at open.canada.ca, and the data providers referenced therein.

Assess the importance of atmospheric deposition of contaminants as a contributor to ecological impacts of oil sands development and identify sources. • Use snowpack measurements sampled across a gridwork to develop maps of winter-time atmospheric contaminant loadings for the region ~100 km from the major upgrading facilities • Assess long-term trends in winter-time atmospheric deposition • Determine the potential impact of wintertime snowpack mercury loads on tributary river water mercury concentrations (Spring Freshet) using Geographic Information System and hydrological modelling approaches • Compare snowpack loadings to those obtained from precipitation monitoring and compare spatial patterns to PAC air measurements obtained from passive sampling networkAll data are subjects of a publication containing method details, full QA/QC, interpretations and conclusions. Citations:A. Dastoor, A. Ryjkov, G. Kos, J. Zhang, J.L. Kirk, M. Parsons, A. Steffen. 2021. Impact of Athabasca oil sands operations on mercury levels in air and deposition. Atmospheric Chemistry and Physics 21, 12783-12807. L. Chibwe, D.C.G. Muir, Y. Gopalapillai, D. Shang, F. Yang, J.L. Kirk, C. Manzano, B. Atkinson, X. Wang, C. Teixeira. 2021. Long-term spatial and temporal trends, and source apportionment of polycyclic aromatic compounds in the Athabasca Oil Sands Region. Environmental Pollution 268A, 115351. J. Culp, I. Droppo, P. di Cenzo, A. Alexander-Trusiak, D. Baird, S. Beltaos, G. Bickerton, B. Bonsal, R. Brua, P. Chambers, Y. Dibike, N. Glozier, J.L. Kirk, L. Levesque, M. McMaster, D.C.G. Muir, J. Parrott, D. Peters, K. Pippy, J. Roy. 2021. Ecological effects and causal synthesis of oil sands activity impacts on river ecosystems: water synthesis review. Environmental Reviews 29. Doi: https://doi.org/10.1139/er-2020-0082. Y. Gopalapillai, J. L. Kirk, M.S. Landis, D.C.G. Muir, C.A. Cooke, C.A., A. Gleason, A. Ho, E. Kelly, D. Schindler, X. Wang, G. Lawson. 2019. Source analysis of pollutant elements in winter air deposition in the Athabasca oil sands region: A Temporal and Spatial Study. ACS Earth and Space Chemistry 38, 1656-1668. W. Wasiuta, J.L. Kirk, P.A. Chambers, A.C. Alexander, F.R. Wyatt, R.C. Rooney, C.A. Cooke. 2019. Accumulating mercury and methylmercury burdens in watersheds impacted by oil sands pollution. Environmental Science & Technology 53, 12856-12864. C. Manzano, D. Muir, J. L. Kirk, C. Teixeira, M. Siu, X. Wang, J.P. Charland, D. Schindler, E. Kelly. 2016. Temporal variation in the deposition of polycyclic aromatic compounds in snow in the Athabasca Oil Sands area of Alberta. Environmental Monitoring and Assessment 188, 542. andJ.L. Kirk, D. Muir, A. Gleason, X, Wang, R. Frank, I. Lehnherr, F. Wrona. 2014. Atmospheric deposition of mercury and methyl mercury to landscapes and waterbodies of the Athabasca oil sands region. Environmental Science & Technology 48, 73747383.

This dataset contains observations of species occurrences from seafloor imagery collected by the autonomous underwater vehicle (AUV) during the 2012 Expedition to Cobb Seamount. The National Oceanographic and Atmospheric Administration-operated SeaBED-class AUV which collected photographic images from 4 transects ranging from 436 m to 1154 m in depth.

Annual and five-year (5YA) average wet deposition maps for the nitrate ion are available. The file formats include geodatabase files (*.gdb) compatible with geospatial software (e.g. ESRI ArcGIS) and KMZ files compatible with virtual globe software (e.g. Google Earth™). Maps can also be viewed online via Open Maps and the ArcGIS online viewer. Annual deposition from each site was screened for completeness using the following criteria: (1) precipitation amounts were recorded for >90% of the year and >60% of each quarter, and (2) nitrate concentrations were reported for >70% of the precipitation measured over the year and for >60% of each quarter. Five-year average wet deposition values are averaged annual deposition values with a completeness criterion >60% for the five-year period. Units for wet deposition fluxes are in kg of NO3 per hectare per year (kg ha-1 y-1). Sources of measurement data and spatial interpolation method are described here: https://doi.org/10.18164/e8896575-1fb8-4e53-8acd-8579c3c055c2.Recommended citation: Environment and Climate Change Canada, [year published]. NO3 Wet Deposition Maps. Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada. [URL/DOI], accessed [date].Recommended acknowledgement: The author(s) acknowledge Environment and Climate Change Canada for the provision of Canada-U.S. wet deposition kriging maps accessed from the Government of Canada Open Government Portal at open.canada.ca, and the data providers referenced therein.

Air emissions from oil sands development can come from a number of sources including industrial smokestacks, tailings ponds, transportation, and dust from mining operations. Air quality monitoring under the Joint Canada-Alberta Implementation Plan for the Oil Sands is designed to determine the contribution of emissions from oil sands activities to local and regional air quality and atmospheric deposition both now and in the future. Ambient air quality data include: - Filter Pack (24-hour integrated concentrations of particle-bound SO2-4, NO-3, Cl-, NH+4, Ca2+, Mg2+, Na+, K+ and gaseous SO2 and HNO3 collected daily by the Canadian Air and Precipitation Monitoring Network) - Total Gaseous Mercury (hourly mixing ratios measured by the Canadian Air and Precipitation Monitoring Network and Prairie and Northern Region) - Atmospheric speciated mercury (Hg) (2-hour average concentrations of gaseous elemental Hg (GEM), reactive gaseous Hg (RGM), and Hg on PM2.5 (total particulate Hg - TPM) - Comprehensive set of measurements collected from an aircraft (various time resolutions) covering an area of 140,000 km2 over the oil sands region - Comprehensive set of measurements collected from the Fort McKay Oski-ôtin monitoring site - Ozone (hourly mixing ratios measured by the Canadian Air and Precipitation Monitoring Network) - Ozone Vertical Profiles (ozone mixing ratios as a function of height) measured by the Canadian Ozone Sonde Network - Aerosol Optical Depth (measure of the degree to which the presence of aerosols in the atmosphere prevents the transmission of light, from the ground to the top of the atmosphere) measured as part of the AErosol RObotic CANadian (AEROCAN) network - Satellite overpass data have a relatively high spatial resolution over the Oil Sands region to produce images and geo-referenced data of nitrogen dioxide (NO2) and sulphur dioxide (SO2) “vertical column density” (which correlates with surface concentration)

The Canadian Seasonal to Inter-annual Prediction System (CanSIPS) carries out physics calculations to arrive at probabilistic predictions of atmospheric elements from the beginning of a month out to up to 12 months into the future, resulting in seasonal forecasts. Atmospheric elements include temperature, precipitation, wind speed and direction and others. This product contains raw numerical results of these calculations. Geographical coverage is global. Data is available on a grid at a horizontal resolution of 2.5 degrees and 1 degree and for a few selected vertical levels. In addition, forecast probabilities for below, near, and above normal temperature and precipitation are available at both resolutions. Predictions and corresponding hindcast are made available monthly.

The Regional Ensemble Prediction System (REPS) carries out physics calculations to arrive at probabilistic predictions of atmospheric elements from the current day out to 3 days into the future. The probabilistic predictions are based on 20 ensemble members that are perturbed through their initial and boundary conditions as well as physical tendencies. A control member that is not perturbed is also available. Atmospheric elements include temperature, precipitation, cloud cover, wind speed and direction, humidity and others. This product contains raw numerical results of these calculations. Geographical coverage includes Canada and the United States. Data is available at a horizontal resolution of 10 km. Data is available on ten vertical levels. Predictions are performed four times a day.