Table of Contents

• Coverage
• Dataset Description
  • Methods & Sampling
  • Data Processing Description
• Data Files
• Parameters
• Project Information
• Funding

Physical indicators of winter climate variability (coastal upwelling, sea level, precipitation) influenced by the winter North Pacific High. The data are all anomalies (normalized to a mean of 0 and std dev of 1) and thus have no units.

Data include:
North Pacific High: Mean Jan-Mar Hadley Centre HadSLP2 sea level pressure anomaly for the region 25N and 35N by 145W and 125W. Data were acquired through: http://www.metoffice.gov.uk/hadobs/hadslp2/

River Discharge: Water year discharge (Oct 1-Sep 30) anomaly for seven rivers, and the mean of these anomalies. Data acquired from the United States Geological Survey https://waterdata.usgs.gov/nwis/rt

Sea Level: Winter (Jan-Mar) anomaly of sea level at five locations along the west coast of North America as well as their mean. All linear trends have been removed. Sea level data were acquired from the University of Hawaii Sea Level Center. http://uhslc.soest.hawaii.edu/

Upwelling: Winter (Jan-Mar) upwelling anomaly for eight upwelling stations (30N, 33N, 36N, 39N, 42N, 45N, 48N, 51N) along the west coast of North America as well as their mean. Upwelling data were acquired from the NOAA Pacific Fisheries Environmental Laboratory. https://www.pfeg.noaa.gov/products/PFEL/modeled/indices/upwelling/NA/upwell_menu_NA.html

Precipitation: Winter (Jan-Mar) precipitation anomaly for thirteen NOAA climate divisions in western North America, as well as their mean. Precipitation data were acquired from the NOAA Climatic Data Center https://www7.ncdc.noaa.gov/CDO/CDODivisionalSelect.jsp

Time series were screened for a North Pacific High (NPH) correlation at values of r < -0.4 for river discharge, r > 0.4 for upwelling, r < -0.5 for sea level and NOAA divisional precipitation, and r < -0.6 for CRU gridded precipitation over the interval 1948-2015. These time series were then analyzed for trends in variance and synchrony, as described in Black et al. Rising synchrony in North American Ecosystems (submitted to Nature Climate Change).

These data are all anomalies in which the time series had been standardized to a mean of zero and standard deviation on one. Linear trends have been removed from sea level data to remove possible geological or anthropogenic sea level rise signals.

BCO-DMO Processing:
- modified parameter names (column headers) to conform with BCO-DMO naming conventions;
- replaced blank spaces/missing data with "nd" ("no data").

Desciption from NSF award abstract:
Along the west coasts of North and South America, Africa, and Iberia, alongshore equatorward winds bring nutrient-rich waters to the sunlit surface of the ocean, stimulating phytoplankton blooms that support robust, rich and diverse ecosystems. This process is known as "upwelling". Because upwelling is driven by winds, and winds are related to atmospheric conditions, upwelling is highly vulnerable to the effects of climate change. However, the potential impacts of climate change on upwelling and biology remain largely uncertain. In earlier work in the California Current upwelling system, off the west coast of the United States, researchers found that upwelling occurs in distinct winter and summer "modes" that have different impacts on biology. In this project, oceanographic and atmospheric data from the Benguela Current system, off South Africa and Namibia, will be analyzed for similar seasonal patterns and relationships with the ecosystem. Comparisons between these two upwelling systems will allow researchers to investigate if previous findings of regional climate impacts on biology are applicable at a global scale and consider how these systems may change in the future. The project will facilitate collaboration between researchers from South Africa, Namibia, and the United States, integrating a team of young and senior scientists from the three countries and providing them with opportunities for broad-scale scientific synthesis early in their careers.

This project will be a comparative analyses of climate forcing and biological responses in the California Current (CCS) and Benguela Current systems (BCS), the two upwelling systems with the most similar time series of atmospheric and oceanographic conditions, seabird demography, and lower (chlorophyll) and mid (forage fish) trophic data. The project will determine whether changes in the ecosystems can be attributed to regional or global climate processes. Growth-increment chronologies from fish in the BCS (deep-water hake) will be developed as indicators of upper-trophic fish growth, and compared to rockfish growth chronologies developed in the CCS. Mid-trophic level fish abundance will be modeled as indices of prey availability for integration between climate and upper-trophic-level parameters. Oceanographic and atmospheric data will be analyzed from global observational and reanalysis data sets, as well as from earth system model projections of climate change. The project will address the following questions:
1) are seasonal upwelling modes (winter and summer) discernible in the BCS as they are in the CCS?
2) are upwelling modes forced by similar or contrasting atmospheric forcing mechanisms?
3) is there evidence of coherence/covariance among mid-trophic fish, upper-trophic fish, and seabirds (and at which lags) within and between the CCS and BCS?
4) will the positioning and amplitude of the atmospheric pressure systems that result in upwelling-favorable winds change coherently between ecosystems under various climate-change scenarios? and
5) what are the fisheries and wildlife management implications for variability in the seasonality and spatial distribution of upwelling in a changing climate?