AIRS and the GCSS Pacific Cross-section Intercomparison (GPCI): - - PowerPoint PPT Presentation

▶
airs and the gcss pacific cross section intercomparison
SMART_READER_LITE
LIVE PREVIEW

AIRS and the GCSS Pacific Cross-section Intercomparison (GPCI): - - PowerPoint PPT Presentation

Apr 01, 2023 210 likes •400 views

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California AIRS and the GCSS Pacific Cross-section Intercomparison (GPCI): Evaluating the Physics of Climate Models Joao

slide-1
SLIDE 1

1

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

Joao Teixeira(1), S. Cardoso (NCAR/IDL) and the GPCI Team (1) Jet Propulsion Laboratory California Institute of Technology Pasadena, California, USA AIRS STM meeting, Caltech, April 2008

AIRS and the GCSS Pacific Cross-section Intercomparison (GPCI): Evaluating the Physics of Climate Models

For more info contact Joao Teixeira at: teixeira@jpl.nasa.gov

slide-2
SLIDE 2

2

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

IPCC 2007:

  • “Water vapor changes represent the largest feedback

affecting climate sensitivity and are now better understood”

  • “Cloud feedbacks remain the largest source of uncertainty”

Climate Change and the Water Vapor and Cloud feedbacks

Cloud regimes in tropical/sub-tropical regions play a key role

slide-3
SLIDE 3

3

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

GCSS/WGNE Pacific Cross-section Intercomparison (GPCI) Sea Surface Temperature

GPCI is a working group of the GEWEX Cloud System Study (GCSS) – funded by the NASA MAP Program Models and observations are analyzed along a transect from

stratocumulus, across shallow cumulus, to deep convection

Models: GFDL, NCAR, UKMO, JMA, MF, KNMI, DWD, NCEP, MPI, ECMWF, BMRC, NASA/GISS, UCSD, UQM, LMD, CMC, CSU, GKSS

  • 1 2

5 8 11 14 17 20 23 26 29 32 35 288 290 292 294 296 298 300 302

SST (K) latitude (degrees) AM2 ARPEGE CAM 3.0 GSM0412 HadGAM RAC GME JJA 1998

ISCCP Low Cloud Cover (%)

slide-4
SLIDE 4

4

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

GPCI Motivation

  • To study important physical regimes and transitions: stratocumulus,

shallow cumulus and deep convection

  • To evaluate models and observations in the tropics and sub-tropics in

terms of the atmospheric hydrologic cycle

  • To utilize a new generation of satellite datasets (e.g. AIRS)
  • To help the development of new cloud, convection and turbulence

parameterizations in climate/weather models

  • To create a database of models and observations for future studies of

the tropics and sub-tropics

slide-5
SLIDE 5

5

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

  • 1 2 5 8 111417202326293235

AM2 cloud cover (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 1 9 9 8

  • 1 2 5 8 111417202326293235

CAM 3.0 cloud cover (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 1 9 9 8

1 2 3 4 5 6 7 8 9

1 2 3 4 5 6 7 8 9

  • 1 2 5 8 111417202326293235

latitude (degrees)

ECMWF cloud cover (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 1 9 9 8

  • 1 2 5 8 111417202326293235

NCEP G&M3 cloud cover (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 1 9 9 8

Cloud Cover along GPCI

Boundary layer clouds Large differences in clouds between models Deep convection clouds

slide-6
SLIDE 6

6

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

  • 1 2 5 8 111417202326293235

latitude (degrees)

AIRS relative humidity (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

10 20 30 40 50 60 70 80 90 10 20 30 40 50 60 70 80 90

  • 1 2 5 8 111417202326293235

latitude (degrees)

NCARv2 relative humidity (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

  • 1 2 5 8 111417202326293235

latitude (degrees)

GFDL relative humidity (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

  • 1 2 5 8 111417202326293235

latitude (degrees)

METOFF relative humidity (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

GPCI mean relative humidity – JJA 2003

slide-7
SLIDE 7

7

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

  • 1 2 5 8 111417202326293235

latitude (degrees)

NCARv2 - AIRS relative humidity (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

  • 100
  • 75
  • 50
  • 40
  • 30
  • 20
  • 10
  • 5

5 10 20 30 40 50 75 100

  • 1 2 5 8 111417202326293235

latitude (degrees)

GFDL - AIRS relative humidity (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

  • 1 2 5 8 111417202326293235

latitude (degrees)

METOFF - AIRS relative humidity (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

Relative humidity differences: model- AIRS (JJA03)

  • 1 2 5 8 111417202326293235

latitude (degrees)

AIRS relative humidity (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

10 20 30 40 50 60 70 80 90

Models are much drier above Sc: AIRS sampling …? UKMO PBL is deeper and/or moister/colder

slide-8
SLIDE 8

8

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

  • 1 2 5 8 111417202326293235

latitude (degrees)

NCARv2 - AIRS relative humidity (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

  • 100
  • 75
  • 50
  • 40
  • 30
  • 20
  • 10
  • 5

5 10 20 30 40 50 75 100

  • 1 2 5 8 111417202326293235

latitude (degrees)

METOFF - AIRS relative humidity (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

Model RH only for TCC < 70%: model- AIRS (JJA03)

  • 1 2 5 8 111417202326293235

latitude (degrees)

NCARv2 - AIRS TCC 70% relative humidity (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

  • 1 2 5 8 111417202326293235

latitude (degrees)

METOFF - AIRS TCC 70% relative humidity (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

Slightly smaller bias above Sc Moist biases decrease Dry biases increase (tropics)

slide-9
SLIDE 9

9

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

10 20 30 40 50 60 70 80 90

  • 1 2 5 8 111417202326293235

latitude (degrees)

AIRS relative humidity STDev (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

AIRS and models relative humidity standard deviation

  • 1 2 5 8 111417202326293235

latitude (degrees)

NCARv2 TCC 70% relative humidity STDev (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

  • 1 2 5 8 111417202326293235

latitude (degrees)

GFDL TCC 70% relative humidity STDev (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

  • 1 2 5 8 111417202326293235

latitude (degrees)

METOFF TCC 70% relative humidity STDev (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

UKMO variability is very different from AIRS, NCAR and GFDL

slide-10
SLIDE 10

10

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

  • 1

2 5 8 11 14 17 20 23 26 29 32 35

latitude (degrees) 0400 hPa JJA 2003 ECMWF AIRS ANALYSIS run_5D_mean RH (%)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (steps)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (steps)

10 20 30 40 50 60 70 80 90

  • 1

2 5 8 11 14 17 20 23 26 29 32 35

latitude (degrees) 0700 hPa JJA 2003 ECMWF AIRS ANALYSIS run_5D_mean RH (%)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (steps)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (steps)

  • 1

2 5 8 11 14 17 20 23 26 29 32 35

latitude (degrees) 0850 hPa JJA 2003 ECMWF AIRS ANALYSIS run_5D_mean RH (%)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (steps)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (steps)

AIRS and ECMWF relative humidity Hoevmoller

  • 1

2 5 8 11 14 17 20 23 26 29 32 35

latitude (degrees) 0400 hPa JJA 2003 AIRS run_5D_mean RH (%)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (steps)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (steps)

  • 1

2 5 8 11 14 17 20 23 26 29 32 35

latitude (degrees) 0700 hPa JJA 2003 AIRS run_5D_mean RH (%)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (steps)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (steps)

  • 1

2 5 8 11 14 17 20 23 26 29 32 35

latitude (degrees) 0850 hPa JJA 2003 AIRS run_5D_mean RH (%)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (steps)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (steps)

ECMWF and AIRS free troposphere is similar Boundary layer is very different

400 hPa 700 hPa 850 hPa

AIRS ECMWF

slide-11
SLIDE 11

11

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (steps) 8 degN JJA 2003 ECMWF AIRS ANALYSIS run_5D_mean RH (%)

1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (steps) 20 degN JJA 2003 ECMWF AIRS ANALYSIS run_5D_mean RH (%)

1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (steps) 32 degN JJA 2003 ECMWF AIRS ANALYSIS run_5D_mean RH (%)

1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

10 20 30 40 50 60 70 80 90

AIRS and ECMWF RH: pressure versus time

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (days) 8 degN JJA 2003 AIRS run_5D_mean RH (%)

1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (days) 20 degN JJA 2003 AIRS run_5D_mean RH (%)

1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

JJA (days) 32 degN JJA 2003 AIRS run_5D_mean RH (%)

1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

AIRS ECMWF Deep cumulus shallow cumulus Stratocumulus Differences are larger in deep cumulus regions

slide-12
SLIDE 12

12

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

Low cloud climate feedback is a surface/boundary- layer/free-troposphere coupled problem

Boundary layer height function of subsidence + entrainment:

LS PBL

dh w w dt = +

Low cloud cover function of low tropospheric

700

stability SST

  • =
  • Cloud cover is function of PBL height: deeper PBL=> less cloud

Klein and Hartman 93

slide-13
SLIDE 13

13

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California 1 6 11 16 21 26 31 36 41 46 51 56 61 66 71 76 81 86 4 8 12 16 20 24 28 32 36 NOTE: LCC from ERAAIRS

LTSS = (700 hPa) - (surface)

AIRS

LTSS 20 deg N

JJA 2003

LTSS (K) days

10 20 30 40 50 60 70 80 90 100

LCC

low cloud cover (%)

1 6 11 16 21 26 31 36 41 46 51 56 61 66 71 76 81 86 4 8 12 16 20 24 28 32 36 NOTE: LCC from ERAAIRS

LTSS = (700 hPa) - (surface)

AIRS

LTSS 29 deg N

JJA 2003

LTSS (K) days

10 20 30 40 50 60 70 80 90 100

LCC

low cloud cover (%)

1 6 11 16 21 26 31 36 41 46 51 56 61 66 71 76 81 86 4 8 12 16 20 24 28 32 36

NCAR

LTSS LTSS = (700 hPa) - SST 08 deg N

JJA 2003

LTSS (K) days

10 20 30 40 50 60 70 80 90 100

LCC

low cloud cover (%)

1 6 11 16 21 26 31 36 41 46 51 56 61 66 71 76 81 86 4 8 12 16 20 24 28 32 36

NCAR

LTSS LTSS = (700 hPa) - SST 20 deg N

JJA 2003

LTSS (K) days

10 20 30 40 50 60 70 80 90 100

LCC

low cloud cover (%)

1 6 11 16 21 26 31 36 41 46 51 56 61 66 71 76 81 86 4 8 12 16 20 24 28 32 36

NCAR

LTSS LTSS = (700 hPa) - SST 29 deg N

JJA 2003

LTSS (K) days

10 20 30 40 50 60 70 80 90 100

LCC

low cloud cover (%)

1 6 11 16 21 26 31 36 41 46 51 56 61 66 71 76 81 86 4 8 12 16 20 24 28 32 36 NOTE: LCC from ERAAIRS

LTSS = (700 hPa) - (surface)

AIRS

LTSS 08 deg N

JJA 2003

LTSS (K) days

10 20 30 40 50 60 70 80 90 100

LCC

low cloud cover (%)

NCAR exhibits a severe lack of LTS variability compared with AIRS

slide-14
SLIDE 14

14

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

Summary

  • Water vapor and cloud feedbacks remain large sources of uncertainty in

climate prediction

  • Cloud regimes in tropics/sub-tropics play a key role
  • GCSS Pacific Cross-section Intercomparison (GPCI) allows for in-depth

study of tropics and sub-tropics

  • AIRS is a key instrument for model evaluation
  • Clouds and thermodynamic variability can be very different between

models and observations

  • Differences between AIRS and models are larger in deep tropics and

boundary layer

slide-15
SLIDE 15

15

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

  • 1

2 5 8 11 14 17 20 23 26 29 32 35

latitude (degrees) cam_av_cling.98000099 (g/Kg)

1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

  • 1

2 5 8 11 14 17 20 23 26 29 32 35

latitude (degrees) hadgam_av_cling.98000099 (g/Kg)

1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

0.005 0.01 0.015 0.02 0.025 0.03 0.035 0.04 0.06 0.08 0.1 0.15 0.2 0.3

g/kg

MeteoFrance NCAR UKMO

Mean liquid water content - JJA98

liquid water

There is a need for observations of cloud and boundary layer (PBL) parameters: PBL height, liquid water,… Too shallow -> fog

Is this too much liquid water?

How deep should the PBL be..?

slide-16
SLIDE 16

16

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

  • 1 2 5 8 111417202326293235

latitude (degrees)

AIRS relative humidity (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

  • 1 2 5 8 111417202326293235

latitude (degrees)

AIRS [ECMWF ANALYSIS] relative humidity (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

10 20 30 40 50 60 70 80 90 10 20 30 40 50 60 70 80 90

  • Rel. humidity: AIRS and ECMWF analysis (with AIRS)
  • 1 2 5 8 111417202326293235

latitude (degrees)

ECMWF AIRS an - AIRS relative humidity (%) 1000 900 800 700 600 500 400 300 200 100

pressure (hPa)

J J A 2 3

  • 100
  • 75
  • 50
  • 40
  • 30
  • 20
  • 10
  • 5

5 10 20 30 40 50 75 100

Smaller bias above stratocumulus Small differences in subtropical upper troposphere

slide-17
SLIDE 17

17

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

10 20 30 40 50 60 70 80 90 10 20 30 40 50 60 70 80 90

160 170 180 190 200 210 220 230 240

longitude (degrees)

AIRS 850hPa relative humidity (%)

  • 5

5 10 15 20 25 30 35 40 45

latitude (degrees) J J A 2 3

160 170 180 190 200 210 220 230 240

longitude (degrees)

NCARv2 - AIRS 850hPa relative humidity (%)

  • 5

5 10 15 20 25 30 35 40 45

latitude (degrees) J J A 2 3

  • 100
  • 75
  • 50
  • 40
  • 30
  • 20
  • 10
  • 5

5 10 20 30 40 50 75 100

160 170 180 190 200 210 220 230 240

longitude (degrees)

GFDL - AIRS 850hPa relative humidity (%)

  • 5

5 10 15 20 25 30 35 40 45

latitude (degrees) J J A 2 3

160 170 180 190 200 210 220 230 240

longitude (degrees)

METOFF - AIRS 850hPa relative humidity (%)

  • 5

5 10 15 20 25 30 35 40 45

latitude (degrees) J J A 2 3

North-East Pacific tropics and sub-tropics 850 hPa RH – climate models versus AIRS

slide-18
SLIDE 18

18

National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, California

Histograms of TCC: ISCCP versus models

0 10 20 30 40 50 60 70 80 90 100

total cloud cover (%)

ISCCP number of events (%)

  • 1

2 5 8 11 14 17 20 23 26 29 32 35

latitude (degrees)

J J A 1 9 9 8

1 2 3 4 5 6 7 8 9

0 10 20 30 40 50 60 70 80 90 100

total cloud cover (%)

HadGAM number of events (%)

  • 1

2 5 8 11 14 17 20 23 26 29 32 35

latitude (degrees)

J J A 1 9 9 8 0 10 20 30 40 50 60 70 80 90 100

total cloud cover (%)

CAM 3.0 number of events (%)

  • 1

2 5 8 11 14 17 20 23 26 29 32 35

latitude (degrees)

J J A 1 9 9 8

ISCCP is between continuous and bimodal

NCAR UKMO

  • NCAR low cloud parameterization is based on climatology =>

continuous transition

  • UKMO (and partly GFDL) cloudy-PBL parameterizations are based
  • n the idea of distinct-regimes => discontinuous transition
  • ISCCP suggests that none of these two “extreme” concepts is fully

valid => relevant for parameterization development