Who We Are and Why We are Here?

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Transcript Who We Are and Why We are Here?

PaCOOS Presentation to Chet Koblinski, Ned Cyr and Jack Dunnigan Scripps Institution of Oceanography, 6 June 2005

Who We Are and Why We are Here?

We are oceanographers and fisheries scientists concerned with the California Current System, the impact of climate variability on ecosystems, and ecosystem-based fisheries management.

We are appealing to NOAA to bring the power of its climate research program, ocean climate observing system, and fisheries research enterprise to study climate impacts on the California Current System Large Marine Ecosystem.

Many of us are involved in planning the Pacific Coast Ocean Observing System (PaCOOS)

Why Study Climate Impacts on Ecosystems in the California Current?

1. There is large, economically important variability of the CCS ecosystem that is connected to physical climate variability by mechanisms that are not well understood .

2.

3.

56-years of study provides a foundation of data, hypotheses and models on climate forcing of the ecosystem as well as a multi-disciplinary collaborative team committed to studying the phenomena.

There is a range of physical mechanisms by which physical climate affects the ecosystem and a range of species that respond differently to these different mechanisms.

ENSO Interannual Variability

Line 80 Line 90 of the CalCOFI Survey Jan 1996 Nutricline Depth El Niño La Niña Oct 1999 Vertically-Integrated Chlorophyll (0-100m) • • • • Rapid changes in physical structure and biological response El Niño: deep thermocline, low productivity La Niña: shallow thermocline, high productvity Monthly sampling needed to observe El Niño evolution Zooplankton Biomass Bograd and Lynn (2001)

Decadal Climate and Ecosystem Variability

CCS zooplankton volume OR coho survival

80% decline Correlation is more than coincidental but mechanisms are unknown

Northern copepods

(from Peterson and Schwing, 2003)

Pacific Salmon Populations

When Alaska salmon are abundant

1900

Washington-Oregon catches are low

2000

(from Mantua et al., 1997)

Sardine Has an Environmentally Based Harvest Plan

When 3-year SST drops below 16.85 o C the allocation drops to 5% of harvestable biomass

Why Study Climate Impacts on Ecosystems in the California Current?

1.

There is large, economically important variability of the CCS ecosystem that is connected to physical climate variability by mechanisms that are not well understood.

2. 56-years of study provides a foundation of data, hypotheses and models on climate forcing of the ecosystem as well as a multi-disciplinary collaborative team committed to studying the phenomena.

3.

There is a range of physical mechanisms by which physical climate affects the ecosystem and a range of species that respond differently to these different mechanisms.

Why Study Climate Impacts on Ecosystems in the California Current?

1.

2.

There is large, economically important variability of the CCS ecosystem that is connected to physical climate variability by mechanisms that are not well understood.

56-years of study provides a foundation of data, hypotheses and models on climate forcing of the ecosystem as well as a multi-disciplinary collaborative team committed to studying the phenomena.

3. There is a range of physical mechanisms by which physical climate affects the ecosystem and a range of species that respond differently to these different mechanisms.

Upwelling, mixing and eddies affect nutrient nutrient supply Temperature, stratification and surface forcing affect behavior and biological rates Advection affects nutrient supply and plankton/egg distribution

What are Our Goals?

To understand the mechanisms for, and extent of, climate variability impacts on CCS ecosystem To use this understanding to predict the consequences to the ecosystem of changes in climate forcing

What is Our General Strategy?

Carefully select species representing different functions in the ecosystem Observe these species well enough to understand their variability Use these observations with models/hypotheses to define mechanisms of climate impact on the ecosystem

What We Will Do

Account for (1) temporal scales from weeks to decades, (2) spatial scales from meters to mega-meters, (3) differing climate impacts on organisms according to their life stage, and (4) strong bio-geographic boundaries and water-mass boundaries that characterize the CCS Use all observational tools (in ships, satellites, moorings, etc.) to synthesize a comprehensive picture of climate and ecosystem variability in order isolate mechanisms (e.g. mixing vs. upwelling, behavior vs. advection) Use models to synthesize diverse observations, to link local and basin-scale variability, and encapsulate what is learned.

Seasonal Variability Dictates Frequent Sampling • • • • Dramatic transition in physical and biological environment • 2-4°C decrease in coastal SST • Large increase in fluorescence Followed establishment of upwelling favorable winds Duration of transition < one month Typical quarterly sampling insufficient to resolve spring transition Frequent and well-timed sampling is also needed to account for the life stages of pertinent organisms Lynn et al. (2003)

38°

Small Scales of Pertinent Variables Must Be Resolved El Nino Year La Nina Year

34° 30° 124° 120° 116° 124° 120° 116°

courtesy of F. Schwing (NOAA Fisheries)

Sampling Must Account for Biogeographic Distributions

Climate Variability Impacts Depend on Biogeographic Preferences

What We Will Do

Account for (1) temporal scales from weeks to decades, (2) spatial scales from meters to mega-meters, (3) differing climate impacts on organisms according to their life stage, and (4) strong bio-geographic boundaries and water-mass boundaries that characterize the CCS Use all observational tools (in ships, satellites, moorings, etc.) to synthesize a comprehensive picture of climate and ecosystem variability in order isolate mechanisms (e.g. mixing vs. upwelling, behavior vs. advection) Use models to synthesize diverse observations, link local and basin-scale variability, and encapsulate what is learned.

Satellites Will Help Describe Carbon Fluxes

Accuracy of ocean color products improved for 1996-2005 time period (OCTS, SeaWiFS, MODIS) compared to 1978-1986 (CZCS)

EOF_1 NOI 0.3

0.2

0.1

0 -0.1

-0.2

1996 -0.3

-0.4

1997 1998 1999 2000 2001 2002

Time

2003 2004 2005

First EOF of Ocean Color (left) shows the response to ENSO as described by the Northern Oscillation (above).

M. Kahru & G. Mitchell

Carbon Export Response to El Nino Varies by Region NOI 1. Northern oligotrophic gyre 2. California coast 3. Baja California coast 4. Gulf of Tehuantepec and the Costa Rica dome Export Flux (mg C m -2 day -1 ) is calculated from Chlorophyll, PAR and SST using the model of Laws (2004)

M. Kahru & G. Mitchell

Stratification and Thermocline Depth Affect Mixing and Upwelling

OFFSHORE COASTAL Temp dT/dZ (dT/dZ) MAX Thermocline Depth

What We Will Do

Account for (1) temporal scales from weeks to decades, (2) spatial scales from meters to mega-meters, (3) differing climate impacts on organisms according to their life stage, and (4) strong bio-geographic boundaries and water-mass boundaries that characterize the CCS Use all observational tools (in ships, satellites, moorings, etc.) to synthesize a comprehensive picture of climate and ecosystem variability in order isolate mechanisms (e.g. mixing vs. upwelling, behavior vs. advection) Use models to synthesize diverse observations, link local and basin-scale variability, and encapsulate what is learned.

Models Now Skillfully Analyze and Predict Physical Variability

Courtesy A. Miller

Ecosystem Models Have Limited Skill and Great Promise

Courtesy A. Miller

Summary

1. CCS has special scientific and personnel advantages for studying climate impacts on ecosystems 2. Correlation of climate variability and ecosystem change is evident but mechanisms are unknown, limiting utility for management and prediction 3. An empirically based approach focused on organisms representing different ecosystem functions is proposed 4.

NOAA’s climate research program and the ocean climate observing system could assist if climate variability that affects ecosystems were part of their focus

What Follows

1. Elizabeth Clarke (NWFSC) will describe the PaCOOS program to which our pilot project is complementary 2. William Peterson (NWFSC/Newport) will describe the proposed hake and sardine demonstration project 3. Frank Schwing (SWFSC/Monterey) will explain why NOAA needs this project in the California Current System 4. Peter Niiler (SIO) will discuss basic research needs for the California Current 5. The NOAA HQ team will lead a discussion of NOAA needs and plans for climate and ecosystem research in the CCS