decadal to century-scale ocean variability and its effects on terrestrial, supramarine, and...
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Decadal to Century-Scale Decadal to Century-Scale Ocean Variability and Its Ocean Variability and Its
Effects on Terrestrial, Effects on Terrestrial, Supramarine, and Submarine Supramarine, and Submarine
ClimatesClimates
A Progress ReportA Progress Report
OutlineOutline
Talk is itself an outlineTalk is itself an outline Some figures to keep you awakeSome figures to keep you awake Proceed in a “legal” rather than a Proceed in a “legal” rather than a
chronological orderchronological order
Global Temperature Datasets Global Temperature Datasets and Long Period Variabilityand Long Period Variability
Land Surface Temperatures: NOAA NCDC Land Surface Temperatures: NOAA NCDC Global Climate Perspectives System, 5 x 5 Global Climate Perspectives System, 5 x 5 degree data, only to 1993degree data, only to 1993
Sea Surface Temperatures: NOAA Sea Surface Temperatures: NOAA Extended Reconstructed Sea Surface Extended Reconstructed Sea Surface Temperature Database, 2 x 2 degree data, Temperature Database, 2 x 2 degree data, 1854-present, problems before 1878 1854-present, problems before 1878
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Spatial Patterns of Long Period Spatial Patterns of Long Period VariabilityVariability
EMD’d the global mean anomalies derived EMD’d the global mean anomalies derived from each datasetfrom each dataset
Added up the trending IMFs as trendAdded up the trending IMFs as trend Removed trend from entire datasetRemoved trend from entire dataset Added together and averaged global spatial Added together and averaged global spatial
patterns for 1/2 sigma, Positive/Negative, patterns for 1/2 sigma, Positive/Negative, AMO/PDOAMO/PDO
Apparently, my AMO convention is wrong…Apparently, my AMO convention is wrong…
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Points Worth Exploring HerePoints Worth Exploring Here
Insights Related to Circulation Change Insights Related to Circulation Change Within Basins and On LandWithin Basins and On Land
Atmospheric Bridge Effects on Other Atmospheric Bridge Effects on Other Oceans, Think Circulation ChangesOceans, Think Circulation Changes
Long Period Variability (in terms of mean Long Period Variability (in terms of mean SST) Seems Dominated by the Smaller SST) Seems Dominated by the Smaller Ocean. Why? Ocean. Why?
PC/EOF/Fourier PC/EOF/Fourier “Linear” Analysis of Local “Linear” Analysis of Local
RegionsRegions ERSST Data, Dave Camp and Xun Jiang ERSST Data, Dave Camp and Xun Jiang
codecode Five regions of interest: Extratropical Pacific Five regions of interest: Extratropical Pacific
and Atlantic (generating PDO and AMO and Atlantic (generating PDO and AMO indices, looking in greater detail); Global indices, looking in greater detail); Global Pacific and Atlantic (slices through whole Pacific and Atlantic (slices through whole basin…what changes?); Southern Indian basin…what changes?); Southern Indian Ocean (What happens here?)Ocean (What happens here?)
Region/Region/PC PC (period(periods)s)
GlobalGlobal
PacificPacific
GlobalGlobal
AtlanticAtlantic
Extra.PExtra.Pacificacific
Extra. Extra. AtlanticAtlantic
SoutheSouthern rn IndianIndian
PC 1PC 1 6.5 yrs.6.5 yrs. 3.5 yrs.3.5 yrs.
62 yrs.62 yrs.
6.5 yrs.6.5 yrs.
Flat 62Flat 62
62, 22-62, 22-2323
PositivPositive trende trend
In S. In S. oceanocean
PC 2PC 2 6.5 6.5 yrs., yrs.,
62 yrs.62 yrs.
23-24 23-24 yrs.yrs.
62, 6.5, 62, 6.5, 1818
1818 XX
PC 3PC 3 XX XX XX Like Like PC 1PC 1
XX
PC 4PC 4 XX XX Weak Weak 6262
XX XX
What’s Worth Exploring HereWhat’s Worth Exploring Here
Causes and Dynamics: The modes that are Causes and Dynamics: The modes that are most significant in analyses probably most significant in analyses probably connected to most detectable modes of connected to most detectable modes of variability; three timescales of importance variability; three timescales of importance (~3-7, 15-25, 50-70)(~3-7, 15-25, 50-70)
Indian Ocean trend of interest. Is it a direct Indian Ocean trend of interest. Is it a direct signal of greenhouse forcing?signal of greenhouse forcing?
EMD Analyses of PCsEMD Analyses of PCs
What It Sounds Like: Mainly Indicates AMO What It Sounds Like: Mainly Indicates AMO Dominates Global Signal on 50-70 year Dominates Global Signal on 50-70 year timescaletimescale
Reconstructed PDO AnalysisReconstructed PDO Analysis
Shen et al. use strong East China rainfall Shen et al. use strong East China rainfall correlation with PDO index to correlate back correlation with PDO index to correlate back to 15th century (hmm…sardines would be to 15th century (hmm…sardines would be nice)nice)
EMD’d the timeseries, came up with various EMD’d the timeseries, came up with various interesting modes: 15.5 yrs., 20-30 yrs., but interesting modes: 15.5 yrs., 20-30 yrs., but the clincher is next with 50-60 vs. 100 yr. the clincher is next with 50-60 vs. 100 yr. modes modes
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What’s Important HereWhat’s Important Here
58, 72-77, 102-106 yr. Modes of variability 58, 72-77, 102-106 yr. Modes of variability common to Pacific sardines and Northern common to Pacific sardines and Northern anchovies from Santa Barbara Basin record anchovies from Santa Barbara Basin record (they anticorrelate in the recent); this (they anticorrelate in the recent); this analysis shows the 102-106 year mode wellanalysis shows the 102-106 year mode well
Some association between century-scale Some association between century-scale mode and Little Ice Age, cold water source mode and Little Ice Age, cold water source in Bering Sea (?), tipping points; Okhotsk in Bering Sea (?), tipping points; Okhotsk (cold now, by the by). (cold now, by the by).
Cursory Forays into Ocean Cursory Forays into Ocean DynamicsDynamics
Why does the switch happen so quickly?Why does the switch happen so quickly? I proposed positive feedback associated I proposed positive feedback associated
with the Aleutian Lowwith the Aleutian Low First Step: Is there a change in the character First Step: Is there a change in the character
of Pacific storminess between PDO of Pacific storminess between PDO phases?phases?
Mean Wind Events Above 23 Mean Wind Events Above 23 ms^-1ms^-1
Mean Wind Events Above 28 Mean Wind Events Above 28 ms^-1ms^-1
Entrainment ExperimentsEntrainment Experiments
C. Pasquero gave me a C. Pasquero gave me a model originally designed model originally designed for nutrient transport for nutrient transport (Price/Weller/Pinker)(Price/Weller/Pinker)
Chose point in middle of Chose point in middle of Pacific, reasonably strong Pacific, reasonably strong winds, repeat buoy data in winds, repeat buoy data in early December, early early December, early January, early February, January, early February, used NOAA Reanalysis used NOAA Reanalysis data to force itdata to force it
Entrainment Experiment Wrap-Entrainment Experiment Wrap-UpUp
Horizontal Transport seems to be important Horizontal Transport seems to be important even on “short” timescaleseven on “short” timescales
Initially thought that heavy storminess could Initially thought that heavy storminess could stir up cooler water from thermoclinestir up cooler water from thermocline
Entirely possible that feedback involves a Entirely possible that feedback involves a change in stratification, in which the upper change in stratification, in which the upper waters become a thin skin that is drained of waters become a thin skin that is drained of heat; need better modelheat; need better model
““Better Models”Better Models”
Linear Analysis of Kirtman AOGCM and Linear Analysis of Kirtman AOGCM and UKMO IPCC RunsUKMO IPCC Runs
Did not produce recognizable patterns of Did not produce recognizable patterns of present behavior, nor did it produce correct present behavior, nor did it produce correct frequency behavior, even on short-termfrequency behavior, even on short-term
ConclusionsConclusions
At present, the work so far done really is of a At present, the work so far done really is of a motivational character rather than a minor motivational character rather than a minor contribution to knowledge; if something is defensible, contribution to knowledge; if something is defensible, it requires further and less desultory defenseit requires further and less desultory defense
The problems that could be tackled are potentially The problems that could be tackled are potentially large and expansivelarge and expansive
We would do better if we restricted our purview to We would do better if we restricted our purview to some minor aspect that would shed some light but some minor aspect that would shed some light but utilize local expertise (remote sensing and/or data utilize local expertise (remote sensing and/or data analysis); and then we talk to the oceanographers…analysis); and then we talk to the oceanographers…
Postlude: Fishy StoriesPostlude: Fishy Stories
Mantua’s Salmon Switch Between Alaskan and Mantua’s Salmon Switch Between Alaskan and Cascadian fisheriesCascadian fisheries
Sardines and Anchovies Out of Phase Population-Sardines and Anchovies Out of Phase Population-Wise During 1970s-1980s transition (Japan, Wise During 1970s-1980s transition (Japan, Peru/Chile, California)Peru/Chile, California)
Benguela Anchovies and Sardines Likewise Out of Benguela Anchovies and Sardines Likewise Out of Phase (But Opposite in Direction)Phase (But Opposite in Direction)
SEAWifs + CalCOFI + Last 8 Years off California, SEAWifs + CalCOFI + Last 8 Years off California, is it possible?is it possible?