Western Tropical Pacific Teleconnections to the Northeast Pacific

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Western Tropical Pacific Teleconnections to the
Northeast Pacific William Crawford Institute of
Ocean Sciences, Fisheries and Oceans Canada,
Sidney, BC, Canada Skip McKinnell Institute of
Ocean Sciences, North Pacific Marine Sciences
Organization, Sidney ,BC Canada Workshop on
Western Tropical Pacific Hatchery for ENSO and
Global Teleconnections, Guangzhou, China, 26-28
November 2007
SST anomaly October 2007
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Links across the Pacific
Catches of Fraser River sockeye salmon are
allotted to Canadian and American fisheries based
on salmon migration routes. This is the richest
Canadian fishery. Both countries negotiate this
treaty based on predictions of return routes in
future years and decades. Salmon prefer the
northern route in warm years. Tempera-ture at
Kains Island in April has been the best predictor
of return routes for 50 years. Early predictions
of temperature at Kains Island help to manage
this fishery.
USA
Fraser River
CANADA
Northern route
Fraser River
Kains Island x
Southern route
Amphitrite Point x
USA
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x
Kains Island Lighthouse is exposed to the
northeast Pacific Ocean. Lighthouse keepers
have measured temperature and salinity daily
since 1934.
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X Kains Island
Correlation between sea surface temperature at
Kains Island in April versus sea level pressure
in January, same year. Data are from
1948-2007. One data pair per year. SLP is
provided by US National Oceanic Atmospheric
Administration (NOAA). The WTP Index in other
plots is from 7.5S 152.5E, in the region of
highest positive correlation.
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Horizontal axis Average sea level pressure (SLP,
millibars) in the western tropical Pacific for
the months of December, January, February.
Vertical Axis Sea surface temperature (SST,
deg. C) measured at Kains Island along Vancouver
Island, the following April. Each years
observations provide a dot on this graph, with
data coverage from 1948 to 2005.
The warmest SST and highest SLP occurred in 1983,
1998 and 1992 all followed El Niño events. The
past two decades have been warmer than in 1950 to
1976. SLP is provided by US National Oceanic
Atmospheric Administration (NOAA).
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El Niño (warm) minus La Niña (cold) composite
average of 200 millibar height in the atmosphere
during January and February (JF). Shading
indicates areas where the warm and cold
composites are significantly different from each
other at the 95 and 99 level ... Heights are
from NCEP reanalysis for events between 1950 and
2000. From Liu Alexander, 2007 Atmospheric
bridge, oceanic tunnel, and global climate
teleconnections. Reviews of Geophysics, 45,
RG2005, doi10.1029/2005RG000172.
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El Niño (warm)La Niña (cold) composite average
of near-surface air temperature during January
and February (JF). Shading indicates areas where
the warm and cold composites are significantly
different from each other at the 95 and 99
level ... Temperatures are from NCEP reanalysis
for events between 1950 and 2000. From Liu
Alexander, 2007 Atmospheric bridge, oceanic
tunnel, and global climate teleconnections.
Reviews of Geophysics, 45, RG2005,
doi10.1029/2005RG000172.
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Average Aleutian Low and North Pacific High for
November to March, 1968-1996
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1983 to present Signals often out of phase
1937 to 1982 Signals mostly in phase
Aleutian Low Pressure Index (ALPI) developed by
McFarlane and Beamish, 1992.
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Warm, ALPI 2.2
Warm, ALPI 0.6
Warm, ALPI 1.9
November-to-March averages over warm and cold
winters
Cold, ALPI 1.8
Cold, ALPI -1.7
Cold, ALPI -1.5
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Anomalies of air pressure at sea level.
Low
La Niña, Victoria Mode, NPGO
High
Warm, ALPI 2.9
Winter average, Nov 2002 to Mar 2003
Low
El Niño, PDO
High
Credit for air pressure maps NOAA/ESRL
Low
Cooler winters always are due to winds blowing
more from the west than southwest.
Cool, ALPI -0.3
High
High
Winter average, Nov 2006 to Mar 2007
http//www.cdc.noaa.gov/cgi-bin/Composites/printpa
ge.pl
http//www.cdc.noaa.gov/cgi-bin/Composites/printpa
ge.pl
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Impacted area is about 250,000 km2, which is 30
larger than the area of Guangdong province of
China.
500 kilometres
The beetle is moving to the NW, but its migration
slowed in 2006-07.
500 kilometres
This beetle kills coniferous trees. In the
winter, temperatures must consistently be below
-35 C or -40 C for several consecutive days to
kill off large portions of mountain pine beetle
populations. In the early fall or late spring,
sustained temperatures of -25 C can kill mountain
pine beetles.
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Analyses of minimum January air temperatures in
100 years of observations (red circles) at eleven
British Columbia meteorological stations. We are
now (2006-2007) at a tidal mixing maximum, which
suggests a winter air temperature minimum.
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X
Wilson, R., Wiles, G., D'Arrigo, R., Zweck, C.,
2006 Cycles and shifts 1,300 years of
multi-decadal temperature variability in the Gulf
of Alaska. Climate Dynamics, doi
10.1007/s00382-006-0194-9. Lunar Nodal Cycle
18.61 years.
X
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McKinnell, S. M., Crawford, W.R., 2007 The
18.6-year lunar nodal cycle and surface
temperature variability in the northeast Pacific.
Journal of Geophysical Research - Oceans, 112,
C02002 doi10.1029/2006JC003671.

• Temperature records reveal convincing evidence of
  an impact of the 18.61-year lunar cycle on
  temperatures from San Diego to Alaska. Although
  no mechanisms have been proven, the Indonesian
  Throughflow and Sea of Okhotsk Outflow are the
  most likely generation regions for oceanic
  anomalies to set up atmospheric teleconnections.

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• Conclusions
• Changes in temperature of Western Pacific Warm
  Pool are linked to changes in temperature of
  coastal regions of the northeast Pacific Ocean.
  These links provide predictability for
  temperatures and also for management of
  fisheries, forests, and other resources and
  activities (2010 Olympics?)
• Temperature records reveal convincing evidence of
  an impact of the 18.61-year lunar cycle on
  temperatures in this region. Although no
  mechanisms have been proven, the Indonesian
  Throughflow and Sea of Okhotsk Outflow are the
  most likely generation regions.
• A stronger Aleutian Low since 1977 is likely
  linked to a warmer Western Warm Pool, and warmed
  the coastal northeast Pacific in the past 30
  years.
• Recently this warming has stopped, likely due to
  stronger westerlies.
• An ensemble of 10 climate models approved by IPCC
  suggests this northward movement of the Aleutian
  Low and increased westerlies is consistent with
  expected climate warming.