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Seattle 2006

Letelier. Seattle 2006. IERP. Large Scale Changes in the North Pacific. Ricardo M Letelier College of Oceanic and Atmospheric Sciences Oregon State University Seattle May 2, 2006. Letelier. Seattle 2006. IERP. Ecosystem structure: species composition (abundance and diversity)

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Seattle 2006

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  1. Letelier Seattle 2006 IERP Large Scale Changes in the North Pacific Ricardo M Letelier College of Oceanic and Atmospheric Sciences Oregon State University Seattle May 2, 2006

  2. Letelier Seattle 2006 IERP • Ecosystem structure: • species composition (abundance and diversity) • diversity within or across trophic levels • carbon, nitrogen, chl in size categories • Ecosystem function: • rates of production, respiration, recruitment • bioelemental and energy fluxes • sink or source for greenhouse gases • How does environmental variability affect ecosystem structure and function?

  3. Time-space scales of physical processes F Z P B Letelier Seattle 2006 IERP

  4. Letelier Seattle 2006 IERP Small spatial scales: mm Schematic diagram of the microhabitat around a marine snow aggregate Physical, chemical and biological processes all operate within this microzone C. Turley, 2002. 0.5 - 20 millimeters

  5. Slightly larger spatial scale: meters chl sigma-t sigma-t vel Profile taken over Oregon shelf in 80m of water N2 phytoplankton vertical gradients linked to small-scale vertical shear, under stable stratification Letelier Seattle 2006 IERP T. Cowles unpubl.

  6. Larger still: 100s of km Acoustic surveys for Hake in a warm and a cool year 1998 2001 Source: NMFS acoustic surveys Letelier Seattle 2006 IERP

  7. Letelier Seattle 2006 IERP Motivation: Early observations by Dave Karl and his team HOT Pacific Decadal Oscillation warm phase cool phase HOT Karl et al. (2001)

  8. Letelier Seattle 2006 IERP A general hypothesis regarding how ocean biology responds to changes in large scale physical forcing. Karl et al. (1999)

  9. Pacific Decadal Oscillation & SRP availability • The HOT data suggest that an inverse relationship exists between SRP availability in the upper euphotic zone and PDO Index Cross-correlation analysis of nutrients relative to PDO Index 0.5 0.25 3 NO3- Correlation coeff. 0 2 -0.25 1 SRP PDO Index -0.5 0 335 -365 -265 -165 -65 35 135 235 Lag time, days -1 -2 -3 89 90 91 92 93 94 95 96 97 98 99 2000 01 02 03 04 From N. Mantua (U.W) Time, years Letelier Seattle 2006 IERP

  10. Letelier Seattle 2006 IERP Prymnesiophytes • Phytoplankton taxa display • distinct long term patterns of • variability Chrysophytes Diatoms

  11. Letelier Seattle 2006 IERP Mesozooplankton trends Oblique tows from 160m to surface with 200 mmnesh size From Sheridan & Landry 2004

  12. Letelier Seattle 2006 IERP Upper water column stability and mixed layer depth From R. Lukas (U.H.)

  13. Assessing the contribution of mesoscale events to the variance in SSH 200 SSH residual, mm 150 91 01 1988 89 90 92 93 94 95 96 97 98 99 2000 02 03 04 Time, years 100 SSH residuals Power spectrum density 50 PDO Index 105 0 104 -50 • Power spectrum analysis of SSH anomaly from TOPEX/Aviso time-series suggests an increase of high frequency contribution to the variance during periods when the PDO index is positive (warm). 103 E(m/s)2 -100 102 101 -150 1.0 -200 100 10-1 10-2 10-3 f(cycles/day) Letelier Seattle 2006 IERP

  14. Letelier Seattle 2006 IERP albacore distribution and SST shifts: 1995-98 vs. 1999-2003 % troll landings east of 140W July-Aug SST change: (1999-2003)-(1995-1998) 99-03 95-98 Source: Jeff Polovina

  15. Letelier Seattle 2006 IERP Alaska and PNW salmon production are out of phase (Hare et al 1999, Fisheries) From Nathan Mantua

  16. Letelier Seattle 2006 IERP Is wave climate changing? What are the implications for the sediment-water interface? Winter Sig. Wave Ht. (m) from Allan & Komar (2000), EOS

  17. Letelier Seattle 2006 IERP Global warming key oceanographic processes for OPI coho (?) PDO ENSO Coastal upwelling Eddies and fronts Time Scale Spatial scale http://www.coas.oregonstate.edu

  18. Upscaling observations (and/or simulation output) Global gridded climate data Satellite SSTs and SSHs Process studies Coastal radar Letelier Seattle 2006 IERP

  19. Letelier Seattle 2006 IERP Linking physical and biological observations:Ocean conditions and Coho survival Logerwell et al. 2003, Fish. Oc. R2= .75 “Ocean Conditions” = F(wtr/spring stratification (SST), spring transition date, transport and upwelling (SL), and first winter (SST)

  20. Letelier Seattle 2006 IERP Linking physical and biological observations:Synthesis reveals physical and ecological structure 5m chlorophyll 5m temperature seabird biomass Chinook coho humpback whales Copepod biomass Batchelder et al, 2002: GLOBEC CCS program, Oceanography

  21. Letelier Seattle 2006 IERP New analytical techniques: Ecological genomics Craig Venter et al extracted microbial DNA from 1.5 m3 of surface seawater. They found 1.2 million new (unknown) genes(reported in March, 2004) This finding poses significant challenges to the emerging field of marine molecular microbial ecology and evolutionary biology. • What are these genes? • Are they unique? • How distinct are the organisms from which these genes were extracted? • Will this scope of diversity be observed in phytoplankton, zooplankton?

  22. Letelier Seattle 2006 IERP NOT EVEN THE TIP OF THE ICEBERG! T. Newberger Knowns Unknowns • Less than 1% of species • Only 1 “model” system • Novel organisms and habitats • Novel physiology/biochemistry

  23. Letelier Seattle 2006 IERP

  24. Letelier Seattle 2006 IERP Steering Committee We are somewhere within this bracket

  25. Important but not discussed • Human imprint on the ocean, particularly the coastal ocean (water cycles, hypoxia, HAB, …..) • Management implications of change due to intermittent forcing • Implications of changing ecosystem boundaries under climate change

  26. How do we evolve to tackle some future challenges ? • Marine genomics and proteomics (from bacteria to nekton) • Bringing biological diversity and functional plasticity into observations and models • Ecological Theory: Bridging observations, theories, and models • Bioinformatics: Interdisciplinary synthesis of large datasets • Observational technology development

  27. Letelier Seattle 2006 IERP How do we get from the marine food web to a global assessment of elemental fluxes??? With great difficulty!

  28. “In the absence of time-series data sets, contemporary field observations are hidden in the ‘invisible present’” John Magnuson 1990 Bioscience 40: 495

  29. We are studying a moving target !!

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