Validation of model clouds using synthetic brightness temperature

model and satellite images

Zhian Sun1, Lawrie Rikus1, Charmaine Franklin1 , Luo San2 and Xiaogu Zheng2

1Center for Australian Weather and Climate Research2 College of Global Change and Earth System Science,

Beijing Normal University, China

The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

Synthetic brightness temperature model

• Offline radiation code same as one used in NWP model but generates radiance brightness temperature as seen by satellite.

• Physical parameterizations same as those in NWP model, e.g. Cloud cover, microphysics, optical properties.

• BT is determined using the model forecast fields and compared with real-time satellite imagery.

• Synthetic BT code has been operational at Bureau for more than 10 years

• Synthetic BT images are available on web once NWP forecasting finishes

• Results can be directly compared with the real time satellite images

The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology

TC LuaBase Date: 20120315 Base Time: 12UTC

The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

GMS5 min 196K

Model min 222K

7th June 2002 GMS5: MIN 186K 4/7/01

Model: MIN 227K

The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

Factors influencing BT

• Cloud top height

• Cloud optical properties

• Cloud microphysical properties

• Cloud amount

The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

GMS5 MIN 196K

Model MIN 205K

MIN: 227K

The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

50 hPa 100 hPa

200 hPa850 hPa

TROP

The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

IAP AREM model

The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

Satellite FY-2CGOES-8/9/10

METEOSAT-5/6

MODIS MTSAT-1R MTSAT2

NOAA-7/8/9/10/11/

12/14/15/16/17

Number of Channels

3 9 6 10 3 3 18

Number of bands

12 24 26 32 9 8 48

SatelliteChannels

ir1

ir2

wv

ir1

ir2

wv

ir1

wv

27/28/ 29/30/ 31/32/ 33/34/ 35/36

ir1

ir2

wv

ir1

ir2

wv

Ch4

Ch5

The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology

JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 115, D00H34, doi:10.1029/2009JD012384, 2010

Our plan• Using BT code to diagnose possible problems in

cloud properties in southern hemisphere• Implement visible and microwave channels to

enhance BT code ability for diagnosing properties in low level clouds

• Produce large amount of model and satellite BT covering the southern ocean areas for diagnostic and statistic studies

• This work may be combined with COSP for analysis of ACCESS model clouds

The Centre for Australian Weather and Climate ResearchA partnership between CSIRO and the Bureau of Meteorology