clara deser, ncar symposium in honor of maurice blackmon

Clara Deser, NCAR

Symposium in Honor of Maurice Blackmon

Clara Deser, NCAR

Symposium in Honor of Maurice Blackmon Mentor Extraordinaire

CDCPostdoc 1990-1991Res. Sci. 1992-1996NCARScientist 1997-

Clara Deser Marika HollandBette Otto-Bliesner

CGD Women Scientists Hired by Maurice Blackmon

Blackmon and Bjerknes:Air-Sea Interaction in the North Atlantic

Clara Deser, NCAR

Blackmon J.Bjerknes

Synoptic MeteorologyENSO

North Atlantic Air-Sea Interaction

Year-to-year variability

Multi-decadal trends:Ocean forcing atmosphere?

Composite SLP, SSTHigh (1904, 1913, 1920) minusLow (1902, 1909, 1915)

1920-1924 minus 1894-1898

“Atlantic Air-Sea Interaction” Jacob Bjerknes, 1964, Adv. in Geophysics 82 pp

Year-to-year variability:

Multi-decadal trends:Ocean forcing atmosphere?

Composite SLP, SSTHigh (1904, 1913, 1920) minusLow (1902, 1909, 1915)

1920-1924 minus 1894-1898

W

C

H

L

“Atlantic Air-Sea Interaction” Jacob Bjerknes, 1964, Adv. in Geophysics 82 pp

Year-to-year variability:Atmosphere forcing ocean

Multi-decadal trends:Ocean forcing atmosphere?

Composite SLP, SSTHigh (1904, 1913, 1920) minusLow (1902, 1909, 1915)

1920-1924 minus 1894-1898

W

C

H

L

“Atlantic Air-Sea Interaction” Jacob Bjerknes, 1964, Adv. in Geophysics 82 pp

Year-to-year variability:Atmosphere forcing ocean

Multi-decadal trends:Ocean forcing atmosphere?

Composite SLP, SSTHigh (1904, 1913, 1920) minusLow (1902, 1909, 1915)

1920-1924 minus 1894-1898

W

C

H

L

H

L

C

W

“Atlantic Air-Sea Interaction” Jacob Bjerknes, 1964, Adv. in Geophysics 82 pp

Year-to-year variability:Atmosphere forcing ocean

Multi-decadal trends:Ocean forcing atmosphere?

Composite SLP, SSTHigh (1904, 1913, 1920) minusLow (1902, 1909, 1915)

1920-1924 minus 1894-1898

W

C

H

L

H

L

C

W

Gulf Stream “Warming”(Bjerknes, 1964)

+3 °C

+3 °C

1890 1900 1910 1920 1930

Year-to-year variability:Atmosphere forcing ocean

Multi-decadal trends:Ocean forcing atmosphere?

Composite SLP, SSTHigh (1904, 1913, 1920) minusLow (1902, 1909, 1915)

1920-1924 minus 1894-1898

W

C

H

L

H

L

C

W

“Atlantic Air-Sea Interaction” Jacob Bjerknes, 1964, Adv. in Geophysics 82 pp

North Atlantic Air-Sea Interaction Revisited

“Surface Climate Variations over the North Atlantic Ocean during Winter: 1900-1989”

Deser and Blackmon (J. Climate 1993)

“Interdecadal Variations in North Atlantic Sea Surface Temperature and Associated Atmospheric Conditions”

Kushnir (J. Climate 1994)

Comprehensive Ocean-Atmosphere Data Set (COADS)

NOAA OGP “Atlantic Climate Change Program”

Percent of months with data

1901-1920

1881-1900 1941-1960

1961-1980

1861-1880 1921-1940C

OA

DS

Dat

a C

over

age

Warm minus Cold Years 50-60NYear-to-year variability:

Atmosphere forcing oceanW

C

H

L

H

L

C

W

Kushnir 1994

W

W

C

H

L

Kushnir 1994

1950-1964 minus 1970-1984

Multi-decadal trends:Ocean forcing atmosphere?

W

L

Deser and Blackmon (1993)Objective Analysis of Sea Surface Temperature Variability

1960 1970 1980 1990

Sea Ice

SST

EOF 2 (1900-1989)

+-

Deser and Blackmon (1993)Objective Analysis of Sea Surface Temperature Variability

1960 1970 1980 1990

Sea Ice

SST

EOF 2 (1900-1989)

C

W

Associated Surface Winds

+-

Deser and Blackmon (1993)Objective Analysis of Sea Surface Temperature Variability

1960 1970 1980 1990

Sea Ice

SST

EOF 2 (1900-1989)

C

W

Associated Surface Winds

SST, Air T

+-

Deser and Blackmon (1993)Objective Analysis of Sea Surface Temperature Variability

1960 1970 1980 1990

Sea Ice

SST

EOF 2 (1900-1989)

C

W

Associated Surface Winds

ICE

SST, Air T

ICE

SST1960 1970 1980 1990

+-

Atmospheric Response toNorth Atlantic Sea Ice and Sea

Surface Temperature Anomalies

Recent Work

Atmospheric Response toNorth Atlantic Sea Ice and Sea

Surface Temperature Anomalies

Recent WorkShiling Peng

with Ting, Whittaker, Hoerling, Alexander, LiNOAA Climate Diagnostics Center

“The Transient Atmospheric Circulation Response to North Atlantic SST and Sea Ice Anomalies”

(Deser, Tomas and Peng: J. Climate 2007)

Transient Atmospheric Response

Imposed SST AnomalyDec 1 Apr 30

SST climatology + anomaly

SST climatologyInitialCondition

1

InitialCondition

240SST climatologySST climatology + anomaly

Atmospheric GCM Experiments (NCAR CCM3)

+6 °C

Geopotential Height ResponseDay 1 Day 2 Day 3 Day 4 Day 5

Positive Negative Contour interval = 10 mshading: 95% significance

WeeklyResponse 1-5

6-10

11-15

WeeklyResponse 1-5

6-10

11-15

Baroclinic Barotropic

Amplification

Local Hemispheric

Spatial Correlations Between1000mb and 300mb Geopotential Height Responses

Transition at 4 weeks

Bar

ocl

inc

B

aro

tro

pic

Geopotential Height Response

Intrinsic Variability

Geopotential Height Response

Forced byDiabatic Heating

Transient eddy vorticityflux convergence

+ SST - SST

Equilibrium Geopotential Height Response

+ SST

Clara Deser, NCAR

Symposium in Honor of Maurice Blackmon