CM3: Tropical Climate and ENSO

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CM3 Tropical Climate and ENSO
Andrew Wittenberg NOAA/GFDL
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The way we were Annual-mean SST
Obs
CM2.1
Bias
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cube sphere, Zhang closure
CM2.1 cube
CM2.1
DonnerUW
BL TKE
Online aerosols
Zhang -gt CAPE/tau
L48 chemistry
cloud/convect tunings
CM3X
CM3Y
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Annual-mean SST
Obs
CM2.1
CM3X
CM2.1 Bias
CM3X Bias
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Annual-mean precip
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Koppen climate zones (Amazon)
more rain
rainforest
savanna/arid
monsoon/savanna
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Annual-mean zonal wind stress
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Equatorial upper-ocean temperature
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Near-surface ocean temperature stratification
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SST seasonal cycle amplitude
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Precip seasonal cycle amplitude
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ENSO SST amplitude
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NINO3 SST spectrum
semiannual
annual
CM3X
CM2.1
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cube sphere, Zhang closure
CM2.1 cube
CM2.1
DonnerUW
BL TKE
Online aerosols
Zhang -gt CAPE/tau
L48 chemistry
cloud/convect tunings
CM3X
CM3Y
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100yr of equatorial Pacific SSTAs
Obs (ERSST.v3)?
CM2.1
CM3X
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Precip response to ENSO
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Zonal wind stress response to ENSO
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Net surface heat flux response to ENSO
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Low cloud response to ENSO
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Summary of tropics in CM3X (1990 control)?
1. Annual-mean SST, precip, Koppens slightly
better than CM2.1 - except cold Indian Ocean,
seasonally-alternating ITCZ 2. Trade winds
weaker/better over the Pacific - but too strong
over Indian Ocean, too weak over Atlantic 3. Big
cloud changes relative to CM2.1 - convective
zones more high cloud, less low cloud -
equator more low cloud 4. Weaker annual cycle of
equatorial SST - east Pacific cold water is
deeper than in CM2.1 5. Weaker ENSO SSTAs (good),
but shorter period (3.5yr -gt 2.5yr)? - narrower
tau_x response (equatorial cold bias)? - more
westward propagation of SSTAs - weaker damping
(low cloud bias)? - worse semiannual locking
(alternating ITCZ)?
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Subannual zonal wind stress amplitude
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Tropical cyclone frequency
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Tropical cyclone duration
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Net surface heat flux into ocean
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Latent heat flux into ocean
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Shortwave flux into ocean
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High cloud
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Low cloud
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Annual-mean surface relative humidity
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Annual-mean air-sea temperature difference
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Annual-mean OLR
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Upper-ocean heat content
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Indonesian Throughflow
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Wind stress curl response to ENSO
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Latent heat flux response to ENSO
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Shortwave flux response to ENSO
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High cloud response to ENSO
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OLR response to ENSO
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NINO3 wavelet analysis (models)
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NINO3 wavelet analysis (obs)
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Global-mean fluxes at surface TOA
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Tropical-mean fluxes at surface TOA
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Koppen climate zones (Africa)
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Koppen climate zones (Australia)
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Tropical cyclogenesis
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Tropical cyclone distribution