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By E. Colbourne, P. Pepin and G. Maillet Fisheries and Oceans Canada

Fisheries and Oceans Canada. Pêches et Océans Canada. Canada. Ecosystem Variability in NAFO Waters Adjacent to the Newfoundland and Labrador Shelf during the Decade of 2000-2009. By E. Colbourne, P. Pepin and G. Maillet Fisheries and Oceans Canada. OUTLINE. Introduction

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By E. Colbourne, P. Pepin and G. Maillet Fisheries and Oceans Canada

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  1. Fisheries and Oceans Canada Pêches et Océans Canada Canada Ecosystem Variability in NAFO Waters Adjacent to the Newfoundland and Labrador Shelf during the Decade of 2000-2009 By E. Colbourne, P. Pepin and G. Maillet Fisheries and Oceans Canada

  2. OUTLINE • Introduction • Decadal Scale Variability in Meteorological and Oceanographic Climate (1950-2009) • Intra-Decadal Variability in the Physical, Biological and Chemical Environment (2000-2009) • Summary

  3. The Study Area/ Observations • ICNAF 1949-1979 • NAFO 1979-Present • Focused on Physical Observations • Canadian Atlantic Zone Monitoring Program (AZMP) • 1999-Present

  4. Groundfish surveys - Selected stations Atlantic Zone Monitoring Program (AZMP)- a joint initiative of 5 DFO labs- Physical, Biological and Chemical Observations Sections – Spring Summer and fall Fixed stations – Every two weeks Remote Sensing - Bi-weekly composites Continuous Plankton Recorder (CPR)

  5. OUTLINE • Introduction • Decadal Scale Variability in Meteorological and Oceanographic Climate (1950-2009) • Intra-Decadal Variability in the Physical, Biological and Chemical Environment (2000-2009) • Summary

  6. NWA AIR TEMPERATURES NAO AIR TEMP • Highest on record during 2000s • Highest variability during the 1970-1990s SST

  7. NL SHELF SEA ICE EXTENT Sea-Ice Lowest Since 1960s • Sea-Ice Lowest Since 1960s • Highly variable during 1970-1990s

  8. NL SHELF TEMPERATURES STATION 27 • Record High Temp in 2000s • Salinity Record Low in 1990s Record High in 2000s

  9. STANDARD SECTIONS CIL Low Variability in 2000s, 1950S

  10. LABRADOR CURRENT GEOSTROPHIC TRANSPORT • Geostrophic Transport of Labrador Current above average in 2000s.

  11. 1970s 1980s 1990s 1960s 2000s 1950s COMPOSITE CLIMATE INDEX • Standardized Anomalies of 27 Meteorological, Sea Ice, Temperature, Salinity Time Series (Xi-Xmean)/σ (1971-2000)

  12. COMPOSITE CLIMATE INDEX SALINITY

  13. RECAP DECADAL TRENDS • The 1970s, 1980s and 1990s experienced extreme intra-decadal variability with cold/warm, fresh/saline conditions. • The 1990s experienced the most extreme variability and was the coldest and freshest in the 6 decades of observations. • The decade of 2000s was the warmest decade in over 60 years of ocean measurements but very similar to 1960s. • The 2000s showed among the least variability reflecting a continuing warming trend throughout the region.

  14. OUTLINE • Introduction • Decadal Scale Variability in Meteorological and Oceanographic Climate (1950-2009) • Intra-Decadal Variability in the Physical, Biological and Chemical Environment (2000-2009) • Summary

  15. STATION 27 – Zooplankton Biomass • Biomass highly variable, record low in 2008 to near-record high in 2009. • High levels of abundance of large and small copepods in 2009Microcalanus sp., Oithona sp., Pseudocalanus sp. and Oncaea sp. • Warm water species Acartia sp., Centropages sp., and Temora longicornis were at low levels of abundance.

  16. Standard Sections (NL) Zooplankton Abundance • Both small and large copepods demonstrated similar patterns of variation. • Lowest abundances at the start of the time-series, with a gradual increase to a peak between 2004-2006. • After 2006, copepods were about average for the AZMP period. • Other groups carnivores, omnivores and non-copepod secondary producers (meroplankton) exhibited similar patterns.

  17. SALINITY Environmental Forcing and Biogeochemical State • During the 12 years of AZMP observations, the physical environment was characterized by warm saline conditions. • Low intra-decadal variability, reflecting the warming trend throughout the region.

  18. PHYTOPLANKTON NITRATE (0-50 M) Environmental Forcing and Biogeochemical State Standard Sections Station 27 • Most correlations were weak and not consistent across the region. • Phytoplankton at S27 demonstrated consistent negative correlations with most climate indices. • In general, nutrient and phytoplankton had a significantly greater proportion of negative correlations than expected by chance (85/130). Correlation coefficients of environmental variables with biochemical indices

  19. Environmental Forcing and Biogeochemical State 27 Zooplankton Taxa (Standard Sections) • No single environmental variable demonstrated a consistent pattern of correlations with the 27 zooplankton taxa. • And no single zooplankton taxa demonstrated a consistent pattern of correlation with any environmental index. • 59% of the 3080 correlations were positive, which is a significant departure from random. Box-whisker plots of the distribution of Pearson’s correlation coefficient of each index of physical environmental variables (y-axis) with all indices of zooplankton abundance (27 taxonomic groups) from each of the four oceanographic sections.

  20. NUTRIENTS PHYTOPLANKTON ZOOPLANKTON AZMP BIOGEOCHEMICAL COMPOSITE (2000-2009) (Xi-Xmean)/σ (Referenced 1999-2010)

  21. Environmental Forcing and Biogeochemical State • The decade of 2000s was characterized by warm climate conditions. • The biochemical state exhibited a high degree of inter-annual variability during this period.

  22. BIOCHEMICAL SUMMARY 2000s • Nutrient were weakly correlated (-ive) with the physical environment. • Phytoplankton at Station 27 was significantly correlated (-ive) with the physical environment. • Some zooplankton taxa varied by 2-orders of magnitude with a general tendency towards +ive correlations with the physical environment. • No single environmental index provides strong predictive capacity of the biochemical state. • Environmental conditions have not varied sufficiently during AZMP to allow an accurate assessment of the full response of ecosystem productivity to changes in physical drivers of the system.

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