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Centre de Météorologie Spatiale

DP/CMS/R&D – Guy Rochard 28/11/2002

Direction de la Production

PASSIVE MICROWAVE PROTECTION

[email protected]

WMO / EUMETNET / ITWG / SFCGand METEO-FRANCE




ATMOSPHERIC OPACITY IN FREQUENCY RANGE 1-275 GHz

1.E-07

1.E-06

1.E-05

1.E-04

1.E-03

1.E-02

1.E-01

1.E+00

1.E+01

1.E+02

1.E+03

1 26 51 76 101 126 151 176 201 226 251

Frequency (GHz)

Vert

ical

opa

city

(dB

)

Minor constituents

OxygenWater vapour tropical

Water vapour sub-arctic




Sensitivity of brightness temperatureto geophysical parameters over ocean surface

01 0 2 0 3 0 4 0

W IN D S P E E DS A L IN IT Y

L IQ U ID C L O U D S

W A T E R V A P O U R

S E A S U R F A C ET E M P E R A T U R E

F r e q u e n c y ( G H z )∆ T b∆ P i

+

_




Sensitivity of brightness temperatureto geophysical parameters over land surfaces

5 10 15 20 25 30 35 40Frequency (G H z)

Soil m o isture

Vege tation biom assS urface roughness

Integrated w ater vapour

C loud liquid w ater

TbPi




O2 absorption spectrum along a vertical path around 60 GHz (multiple absorption lines)

PASSIVE SENSORS REQUIREMENTS IN O 2 ABSORPTION SPECTRUM AROUND 60 GHz(U.S. standard atmosphère - Absorption model: Liebe 1993)

55.22 GHz

55.78 GHz

RESONANCE FREQUENCIES (GHz)

51.503452.021452.542453.066953.595754.130054.671255.221455.783856.264856.363456.968257.612558.323958.446659.164259.591060.306160.434861.150661.800262.411262.486362.998063.568564.127864.678965.224165.764866.302166.836867.369667.9009

52.6 GHz

50.2-50.4 GHz

Excl.

Excl.

Shared

Tota

l oxy

gen

abso

rptio

n al

ong

a ve

rtica

l pat

h (d

B)

200

100

0

59.3 GHz

50 55 60 65 70Frequency (GHz)




Weigthing functions at 50 to 60 GhZ




Water vapourabsorption spectrumalong a vertical path

around 183 GHz

0

20

40

60

80

100

120

140

160

180

200

174,

81

175,

81

176,

81

177,

81

178,

81

179,

81

180,

81

181,

81

182,

81

183,

81

184,

81

185,

81

186,

81

187,

81

188,

81

189,

81

190,

81

191,

81

Frequency (GHz)

Tota

l abs

orpt

ion

alon

g a

verti

cal p

ath

(dB

Mid-latitudeTropicalSub-arctic




The SAPHIR channelsover the water vapor line

180

185

190

GH

z

175

O L

1 2 3 654123456

183,

31

195

Central Frequencies (GHz)

183,31 ± 0,20

183,31 ± 1,10

183,31 ± 2,70

183,31 ± 4,20

183,31 ± 6,60

183,31 ± 11,00




Weigthing functions at 183 GhZ




ATM OSPHERIC ABSORPTION IN FREQUENCY RANGE 275-1000 GHz

1.E-03

1.E-02

1.E-01

1.E+00

1.E+01

1.E+02

1.E+03

1.E+04

1.E+05

1.E+06

275 325 375 425 475 525 575 625 675 725 775 825 875 925 975

Frequency (GHz)

Vert

ical

opa

city

(dB

)

W ater vapour tropical

W ater vapour sub-arctic

Oxygen

Minor constituents




GOMAS or GEM

Antenna Ø 54 GHz 118 GHz 183 GHz 380 GHz 425 GHz

1 m 242 km 112 km 73 km 35 km 31 km

2 m 121 km 56 km 36 km 18 km 16 km

3 m 81 km 37 km 24 km 12 km 10 km

4 m 60 km 28 km 18 km 8.8 km 7.8 km




INTERNATIONAL TELECOMMUNICATION UNION

RADIOCOMMUNICATIONSTUDY GROUPS

February 2002English only

Draft Revision Of RECOMMENDATION ITU-R SA.515-3Frequency bands and bandwidths used for satellite passive sensing

(Question ITU-R 140/7(1978-1990-1994-

1997-2002)The ITU Radiocommunication Assembly,consideringa) that environmental data relating to the Earth is of increasing importance;




ITU draft REC. SA 515Spectral

Line(s) or Centre

frequency (GHz)

MeasurementFrequency Band(s)(1)

(GHz)

Total BW

required (MHz)

Scan modeN, L(4)

1.37-1.4s,1.4-1.427P

100 1.4 Soil moisture, ocean salinity, sea surface

temperature, vegetation index

N

2.64-2.655s, 2.655-2.69s,

2.69-2.7P

45 2.7 Ocean salinity, soil moisture, vegetation index

N

4.2-4.4s,4.950-4.990s

200 4.3 Sea surface temperature N

6.425-7.25 200 6.85 Sea surface temperature N

10.6-10.68p,10.68-10.7P

100 10.65 Rain rate, snow water content, ice morphology,

sea state, ocean wind speed

N

Spectrumrequirements

for passive sensingof environmental data

Up to

1000 GhZ





RADIOCOMMUNICATIONSTUDY GROUPS February 2002

English only

DRAFT REVISION oF RECOMMENDATION ITU-R SA.1028-1PERFORMANCE CRITERIA FOR SATELLITE PASSIVE

REMOTE SENSING(Question ITU-R 140/7)

(1994-1997-2002)The ITU Radiocommunication Assembly,consideringa) that certain frequency bands, including some absorption bands of atmospheric gases (e.g., O2 (oxygen) and H2O (water vapour) ), have been allocated for spaceborne passive microwave remote sensing;



Direction de la Production ITU draft REC. SA 1028Frequency Band(s) (1)

(GHz)Total BWRequired

(MHz)

Required Te

(K)

Data avaibility

(%)(7)

ScanMode (N,L)(4)

1.37-1.4s,1.4-1.427P

100 0.05 99.9 N

2.64-2.655s,2.655-2.69s,

2.69-2.7P

45 0.1 99.9 N

4.2-4.4s,4.950-4.990

200 0.3/0.05(6) 99.9 N

6.425-7.25 200 0.3/0.05(6) 99.9 N

10.6-10.68p,10.68-10.7P

100 1.0/0.1(6) 99.9 N

15.2-15.35s,15.35-15.4P

200 0.1 99.9 N

18.6-18.8p 200 1.0/0.1(6) 95/99.9(6) N

21.2-21.4p 200 0.2/0.05(6) 99/99.9(6) N

22.21-22.5p 300 0.4/0.05(6) 99/99.9(6) N

23.6-24.0P 400 0.05 99.99 N

Spectrumrequirementsfor passive

sensingof environmental

data

Up to

1000 GhZ





RADIOCOMMUNICATIONSTUDY GROUPS

February 2002English only

DRAFT REVISION of RECOMMENDATION ITU-R SA.1029-1PERMISSIBLE INTERFERENCE CRITERIA LEVELS FOR SATELLITE

PASSIVE REMOTE SENSING(Question ITU-R 140/7)

(1994-1997-2002)The ITU Radiocommunication Assembly,consideringa) that certain frequency bands, including some absorption bands of atmospheric gases (e.g., O2(oxygen) and H2O (water vapour) ), have been allocated for spaceborne passive microwave remote sensing;




DATA AVAILABILITY

Data availability is the percentage of area or time for which accurate data is available for a specified sensor measurement area or sensor measurement time. For a 99.99% data availability, the measurement area is a square on the Earth of 2,000,000 km2, unless otherwise justified; for a 99.9% data availability, the measurement area is a square on the Earth of 10,000,000 km2 unless otherwise justified; for a 99% data availability the measurement time is 24 hours, unless otherwise justified




Long-term objectives for passive sensor sensitivities

Frequencyband(s)((GHz Objective ∆Te (K)

1.37-1.4s,1.4-1.427P 0.05

2.64-2.655s, 2.655-2.69s,

2.69-2.7P 0.05

4.2-4.4s,4.950-4.990s 0.05

6.425-7.25 0.05

10.6-10.68p, 10.68-10.7P 0.1

THE WMO TABLE IS A

DRAFT DEFINED UP TO

1000 GhZ

(not clear for 1000 to 3000 GHz range)




N.B.The updated and consolidated WMO table quoted above

should and must be as well the reference for a correct

agreement between « local » and « global » 1b radiances.

Same concerning the computation of synthetic radiances.

This is …not yet …the case today .

What about tomorrow when using togetherNPOESS, METOP,FY-3 etc …?




WEB(s) sites fore more infos.http://cimss.ssec.wisc.edu/itwg/groups/frequency/

http://guy.rochard.free.fr/meteo/

http://www.eumetnet.eu.org/

http://www.wmo.ch/web/www/TEM/SG-RFC/Handbook.htm

http://www.itu.int/ITU-R/index.html

http://www.sfcgonline.org

[email protected] fore more questions

http://cimss.ssec.wisc.edu/itwg/groups/frequency/

http://www.wmo.ch/web/www/TEM/SG-RFC/Handbook.htm

http://www.itu.int/ITU-R/index.html

http://www.eumetnet.eu.org/

mailto:[email protected]

http://guy.rochard.free.fr/meteo/

http://www.sfcgonline.org/




Some big problems to solve …

To conclude what is needed above 275 GHz (central frequencies and bandwidths)

To conclude about ‘Delta T ‘ tables between WMO and ITU proposals

To archive emissivity pictures of the Earth in microwaves below 50 GHz.

To save 23.6-34 GHz as a key exemple for ever !




Contamination around 7 GHz




Measurementsin the 10.6 to

10.7 GHz band with the

Effelsberg100m radio

telescope

1990

2000




The global problem :

1) To get a clear, consolidated and justificated request (that include for our instruments to avoid « wrong » bands).

2) To make lobbying against those which don’t respect WMO and ITU rules…

3) A first way is to cooperate with SFCG and a complementary way is to react country by country now.




Suggestions from now to next ITSC-14 :

* To have a one hour meeting ,here, with interested people

* To clean and update the informations on ITWG Web

* To host next SFCG/24 in Perros-Guirec in one year

if ITWG agrees

if some money can be collected from :

NASA, NOAA, ESA, EUMETSAT, NASDA, WMO, CNES, ISRO, CSA and some others…

(SFCG-25 is planned in Beijing by september 2005).




SFCG-24 ( 60 people)

A) Two actions given to the ITWG representative :* one bout how to update the WMO/ITU handbook* the other about to complete and consolidate the « table »

from 1 to 3000 GHz for passive microwaves

B) Evaluation of the cost of SFCG-24 at Perros-Guirec30 KEUROS for the facilities of the Conference Center4 KEUROS for the coffee breaks4 KEUROS for the SFCG-24 dinner2 KEUROS for the busTotal 40000 Euros …so around 4000 Euros by Organism.

( answer needed urgently )

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