TROPICAL -- EXTRATROPICAL CONNECTIONS INCLUDING MARK A. CANE
LAMONT-DOHERTY EARTH OBSERVATORY OF COLUMBIA UNIVERSITY PALISADES,
NY 10964 + PAUL GOODMAN AND WILCO HAZELEGER ENSO With Thanks To:
Tony Busalacchi Roger Lukas Rui Xin Huang Jay McCreary Greg Johnson
Mike McPhaden Mojib Latif Mosami Nonaka Zengyu Liu Paola Rizzoli
Slide 2 Which way and where from? From the Tropics to the Globe To
the Equatorial Ocean from the Extratropics Subtropics Tropics What
can change equatorial SST? How? Waves [Adjustment] or Advection: v
T, v T On what time scales? Centennial, Millennial and beyond
Interannual (ENSO) Decadal: Pacific (PDO) Atlantic (NAO) Slide 3
Slide 4 Slide 5 Slide 6 Slide 7 Poleward shift Equatorward shift
Courtesy of Clara Deser r =.60; r =.76 with a 5-year lowpass (sig.=
99%) Slide 8 Slide 9 Advection of anomalous Temperature v T Gu and
Philander Science 1997 Latif and Barnett Science 1994 Deser et al
J. Climate 1996 Zhang et al Science 1998 Slide 10 Hazeleger et al
JGR 2001 Slide 11 Decadal anomalies of the depth of the 0 = 25.5
isopycnal zonally averaged in the shaded region From Schneider et
al, GRL 1999 From a coupled model Slide 12 Hazeleger et al.,
JPO,2001 Change in overturning stream function with added cooling
due to storms Slide 13 Anomalous Advection of mean Temperature
McCreary and Lu JPO 1994 Liu; Liu, Philander and Pacanowski JPO
1994 FIne, Peterson and Ostlund JPO 1987 Johnson and McPhaden JPO
1999 McPhaden and Zhang Nature 2002 the Subtropical Cell v'Tv'T
Slide 14 Meridional Stream Function OCCAM model Eulerian Lagrangian
L-E Hazeleger et al., GRL, 2001 z Slide 15 McPhaden and Zhang
Nature, 2002 Potential Vorticity Zhang et al., JPO submitted. (See
Rizzoli et al., DOA 2000 for a model version) Slide 16 Interior
communication window identified from the virtual streamfunction (in
Sv) Huang and Wang, JPO, 2001 Slide 17 Johnson and McPhaden, JPO,
1999 8S 8N Mass Flux Accumulated down Goodman et al, 2002 To appear
Slide 18 Goodman et al., 2002 Volume Ventilated (10 3 m 3 /s) Slide
19 Goodman et al., 2002 to appear Time Between Subduction and the
EUC (years) Slide 20 10N Eq 5S 13S 6.3 3.8 1.8 8.3 3.50.6 2.0 Slide
21 McPhaden and Zhang Nature, 2002 Slide 22 McPhaden and Zhang,
Nature, 2002 Slide 23 Heat Transports in a model Indo-Pacific Ocean
Hezeleger et al JPO submitted Slide 24 Adjustment Wave Processes
Rossby JMR 1937 Cane and Sarachik JMR 1977, 1981;JPO 1983 Johnson
and Marshall JPO, JGR 2002 Slide 25 Temperature along the equator
Halpern, 1980 Slide 26 H Slide 27 Slide 28 So, a wind anomaly scale
of ~ 10 increases the temperature of upwelled water by ~ 1K. With w
~ 1m/day, Q ~ 50W/m 2 A change in the STC of 0.1 PW (estimated from
the same 0.02 N/m 2 spread from 10S to 10N over 1/3 of the width of
the Pacific is ~10W/m 2 Slide 29 Decadal anomalies of the depth of
the 0 = 25.5 isopycnal zonally averaged in the shaded region From
Schneider et al, GRL 1999 From a coupled model Slide 30 PC
timeseriesDecadal Pattern Forcing region 12N/S 10N/S 7N/S 5N/S
Karspeck and Cane, JPO 2002 Slide 31 McPhaden and Zhang Nature,
2002 Slide 32 Discussion The longer the period the more poleward
the reach. Why is there decadal variability? Is there anything
special about decadal? Decadal Variability is most likely generated
in the tropics the southern hemispere is the next place to go
adjustment is more important than advection Slide 33 It would be
nice to quantify decadal variations in heat budgets. And even nicer
to have a usable theory for what sets and what can change ocean
stratification. But even these wont tell us the sources of decadal
variability: Slide 34 It is a coupled system* ocean atmosphere *at
least in the tropics
