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11/18/02 University of Kansas

Microwave Remote Sensing: Principles andApplications

Outline² Introduction to RSL at the University of Kansas² Introduction and History of Microwave Remote Sensing² Active Microwave Sensors

Radar Altimeter. Scatterometer.

Imaging Radar.

² Applications of Active Sensors

Sea ice. Glacial ice Ocean winds. Soil Moisture. Snow. Vegetation. Precipitation. Solid Earth.




Microwave Remote Sensing: Principles andApplications

Passive Microwave Sensors² Radiometers

Traditional Interferometer

Polarimetric Radiometer Application of Passive Microwave Sensors

Sea ice. Glacial ice Soil Moisture.

Atmospheric sounding Snow. Vegetation. Precipitation




Radar Systems and Remote Sensing

Laboratory

WindvectorMeasurements overthe Ocean

Radar at 14 GHz.Concept developed at

KU.

USA, Europe and

Japan are planningto launch satellitesto obtain datacontinuously.





Laboratory

Founded in 1964.

4 Faculty members, 20 Graduate students - Ph. D & M.S.4-6 Undergraduate students, 2 Staff

Now satellites based on concepts developed at RSL are in

operation. NSCAT, QUICKSCAT- Radars to measure ocean surface winds.

ADEOS-2 (JAPAN), Europeans Met Office is planning to launchsatellite to support operational applications.ScanSAR-

Radarsat- Canadian satellite

Envisat - EuropeanSRTM -Shuttle Radar Topography Mission.Radar Systems

and Remote Sensing Laboratory





Laboratory Shuttle Radar TopographyMission (SRTM)² to collect three-

dimensionalmeasurements of theEarth's surface.

² Acquired data to obtainthe most completenear-global mapping ofour planet's topographyto date.

² This would not have

been possible withoutScanSAR operation---concept developed atKU.




ITTC² Information Technology &Telecommunication Center

Communications academic emphasis andresearch programs established in 1983.

Now RSL is a part of the Center

Graduated students² degrees in EE, CS, CoE, Math29 faculty, 15 staff researchers, 6 Centerstaff

Current student population ~ 130² ~ 13 Ph.D., ~81 M.S., ~37 B.S.




EM Spectrum

Microwave region 300 MHz ² 30 GHz.

Millimeter wave

30 GHz ² 300 GHz.

IEEE uses a differentdefinition

300 MHz ² 100 GHz




Microwave Remote Sensing: Principles andApplications.

Advantages² Day/night coverage.

² All weather except duringperiods of heavy rain.

² Complementaryinformation to that inoptical and IR regions.

Disadvantages

² Data are difficult tointerpret.

² Coarse resolution exceptfor SAR.




Microwave Remote Sensing³ history

US has a long history in Microwave Remote Sensing.

² Clutter Measurement program after theWW-II.

Ohio State University collected a large data

base of clutter on variety of targets.

² Earnest studies for the remote sensing of theearth can be considered to have began 1960s.

In 1960s NASA initiated studies to investigatethe use of microwave technology to earthobservation.




Microwave Remote Sensing³ history

The research NASA and other agencies initiated resulted in:

² Development of ground-based and airborne sensors.² Measurement of emission and scattering characteristics of

many natural targets.² Development of models to explain and understand measured

data.² Space missions with microwave sensors.

NIMBUS

² Radiometers. SKYLAB² Radar and Radiometers




Microwave Remote Sensing

Radar² Radio Detection and

Ranging.

² Texts: Skolnik, M. I.,Introduction to RadarSystems, McGraw Hill,1981.

Stimson, G.W.,Introduction to AirborneRadar, SciTechPublishing, 1998.

Applications

Civilian

Navigation and

tracking

Search and

surveillance

Imaging &

Mapping

Weather

Sounding

Probing

Remote sensing

MilitaryNavigation and

tracking

Search and

surveillance

Imaging &

Mapping

Weather

Proximity fuses

Counter measures




Review ² EM theory and Antennas

Propagation of EMwaves is governed byMaxwell equations.

For time-harmonicvariation we can

write the aboveequations as

V

[Q

[I

V

!

!

!v

!v

!

!x

x!v

x

x!v

D

B

H j E

E j J H

D

B

t

B E

t

D J H

.

0.

.

0.




EM Theory

Helmholtz Equation² From the four

Maxwell equations,

we can derive vectorHelmholtz equations

² For each component

of E and H field wecan write a scalarequation

0

0

0

0

0

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

!x

x

x

x

x

x

!x

x

x

x

x

x

!x

x

x

x

x

x

!

!

!

z z z z

y

y y y

x x x x

E z

E

y

E

x

E

E z

E

y

E

x

E

E z

E

y

E

x

E

where

H H

E E

K

K

K

QI[K

K

K




Uniform plane wave

Amplitude and phase are constant onplanes perpendicular to the direction of

propagation.TEM case² no component in the directionof propagation.

For a TEM wave propagating in z directionEz = 0 and Hz =0

Ex(z,t) = Eo e-z Cos(t-jz)




EM theory

and aredetermined bymaterial properties.

Materials areclassified as

insulators andconductors²

2

conductor aFor

media.loss-lowof examplesaresoildry

andsnowdryice,r Fresh wate

2

mediumloss-lossaFor

[QW FE

[IW

QI[ FI

QWE

[IW

[IW[Q FEK

!!

""

!

}

!! j j j




EM Theory

Reflection andrefraction² Whenever a wave

impinges on adielectric interface,part of the wave willbe reflected andremaining will betransmitted into thelower medium.

i r

t




EM Theory--Scattering

Microwave Scattering from adistributed target depends on

² Dielectric constant.² Surface roughness.

² Internal structure. Homogeneous

Inhomogeneous² Wavelength or Frequency.

² Polarization.




Microwave Scattering

Surface scattering² A surface is classified as

smooth or rough bycomparing its surfaceheight deviation withwavelength.

Smooth h < /32cos()

For example at 1.5

GHz and = 60 deg., h < 1.25 cm

i r

Smooth surface

Moderately roughsurface

Very rough surface





Rough surface scattering





Volume scattering² Material is

inhomogeneous such

as Snow

Firn

Vegetation

Multiyear ice

)()(20

t

o

v s

o

T T UW UWW !





Surface scattering models² Geometric optics model

Surface height standard deviation is large compared to thewavelength.

² Small perturbation model Surface height standard deviation is small compared to the

wavelength.

² Two-scale model

Developed to compute scattering from the ocean² Small ripples riding on large waves.




Antennas

Antennas are used to couple electromagneticwaves into free space or captureelectromagnetic waves from free space.

Type of antennas² Wire

Dipole

Loop antenna

² Aperture Parabolic dish

Horn




Antennas

Antennas are characterizedby their:² Directivity

It is the ratio of maximumradiated power to thatradiated by an isotropic

antenna.² Efficiency

Efficiency defines howmuch of the power is thetotal power radiated by theantenna to that delivered tothe antenna.

² Gain It is the product ofefficiency and directivity

² Beamwidth Width of the main lobe at

3-dB points.

dipole




Antenna gain



11/18/02University of Kansas

Antennas

An array of antennasis used wheneverhigher than

directivity isneeded.² Can be used to

electronic scanning.

² Most of the SARantennas are arrays.




Antenna Array

Let us considersimple arrayconsisting of

isotropic radiators.

sinx

E

.expressionresultingthereduceand

degrees90to0from increaseweIf

sin2cos

)sincos2

sin2

sin

sin

t

)sin2

sinsinsin2

sin(22

1

0

0

0

x

d E E

d ee E E

eeee E E

ee E E

d

d R

d R R

i

oit

d j

R j

ot

d j

d j

d j

R j

ot

d R j

R j

ot

o

o

w

¹ º

¸©ª

¨w

!

¹¹ º

¸©©ª

¨!

¹¹ º

¸©©ª

¨!

!x

!x

!

§

P

UT

P UT

UP

TN

U

U

P

UT

P

T

P

UT

P

UT

P

UT

P

T

P

UT

P

T

P

Ro

d

R1

U




Radar Principles

Radar classifiedaccording to thetrasmit waveform.

² Continuous Doppler

Altimeter

Scatterometer

² Pulse Wide range ofapplications




Radar Principles

Radar measuresdistance bymeasuring time delay

between thetransmit andreceived pulse.² 1 us = 150 m

² 1 ns = 15 cm

Radar

jet.thetoRangeR

n propagatioof velocityc

receptionand

ansmission between tr delaytime

2

!

!

!

!

X

Xc R




Radar³ principle

Unambiguous rangeand Pulse RepetitionFrequency (PRF)

² PRF also determinesthe maximum dopplerwe can measure witha radar³ SAR.

² PRF > 2 fdmax

s1for 150 ,2

10015002

103R

Hz1500f radar withaFor

2

1,

p

8

un

p

QXX

!!(!(

!!

!

!

!

!

mr c

r

k m x

x

f

C R

T f PRF

T PRI

p

p

un

p




Radar³Principle

Radar equation For a monostatic radar

GT = GR

Radar sensitivity is determinedby the minimum detectablesignal set by the receiver noise.

No = kTBF

F= noise figure

Signal-to-noise ratio

2

43

2

T

22

Tr

22

T

ri

2

Tdr

2

Td

4

)4(

P

44

PP

bygivenisitandsignalincidentAe,aperture,effectiveanwithantennareceiveThe

4

1

4

P

P

bygivenisantennaon theincident power Reradiated

4

PP

radar.theof directionin the

reradiatesandsignalthisof parta

intercepts,section,crossradar hTarget wit

4

P P

byPgivenistargetat thedensityPower

P

T

T

WP

TW

T

TWT

WT

W

T

e R

RT r

eT

T

T

T

AGwhere

R

GG P

R

A

R

G

R R

G

R

G

R

G

!

!

!

!

!

!

PT

GT R

4

1

3

22

max

43

22

)4(

)4(

K TB F N

S

G P R

K TB F R

G P

N

P

N

S

T T

T T

o

r

T

WP

T

WP

!

!!

I1



Slide 30

I1 ITTC, 11/11/2002





Radar cross sectioncharacterizes thesize of the object as

seen by the radar.Where

Es = scattering field

Ei = incident field

2

2

2

4

i

s

R Lim

E

E RTW gp!

r

2

r TW !




Radar Equation

A distributed targetcontains manyscattering centers

within theilluminated area. Itis characterized byradar cross sectionper unit area, which

is refereed to asscatteringcoefficient

areaated Illu A

t coe fficien scatter ing

A

o

o

min

!

!

!

W

WW

43

022

)4( R

AG P P T T

r

T

WP!

Fe

R Uo

ae

aeo

eo

R A

If

R R A

F FT

F U

F F U

F U U

T

2

0

0

4

1&1

)2

tan()2

tan()2

tan()cos(2

}

¹ º

¸©ª

¨!

Fa




Radar Equation

16)4(

4)4(

22

022

43

022

aeT T

r

aeT T r

R

G P P

R R

R

G P P

F F

T

WP

F FT

T

WP

!

!

For a distributed power received falls off as 1/R2

For a point target power received falls off as 1/R4




Antenna Array



sinx

E



sin2cos

)sin

cos2

sin2

sin

sin

t

)sin2

sinsinsin2

sin(22

1

0

0

0

x

d E E

d ee E E

eeee E E

ee E E

d

d R

d R R

i

oit

d j

R j

ot

d j

d j

d j

R j

ot

d R j

R j

ot

o

o

w

¹ º

¸©ª

¨w

!

¹¹ º

¸©©ª

¨!

¹¹ º

¸©©ª

¨!

!x

!x

!

§

P

UT

P

UT

UP

TN

U

U

P

UT

P

T

P

UT

P

UT

P

UT

P

T

P

UT

P

T

P

Ro

d

R1

U




Microwave Remote Sensing: Principles andApplications³ History

Active Microwave sensing² Studies related to active sensing of the

earth beagn in 1960s. Clutter studies

SkYLab ² radar altimeter and scatterometer in1960s

SEASAT in 1978

ERS-1, JERS-1, ERS-2, RADARSAT, GEOSAT,Topex-Posoidon




Active Sensors ² Radar Altimeter

Radar altimeter is a short pulse radarused for accurate height measurements.² Ocean topography.

² Glacial ice topography

² Sea ice characteristics Classification and ice edge

Vegetationhttp://topex-www. j pl.nasa.gov/technology/images/P38232. j pg




Radar Altimeter

MissionsSatellite Radar Altimeters

Mission Frequency Accuracy Period

SKYLAB Ku 10 m 1973

GEOS Ku 1-5 M 1976

SEASAT Ku ~1 m 1978

GEOSAT Ku 10 CM 1985-1990

ERS-1 Ku < 10 cm 1992-1998

TOPEX C &Ku < 10 cm 1992-

ERS-2 Ku < 10 cm 1996-

GFO Ku <10 cm 1998-

ENVISAT Ku &S <10 CM 2001-

Jason-1 Ku &C <10 cm 2000-

CRYOSAT and other

missions Ku Few cm 2003-




Radar Altimeter³Waveform

Satellite altimeters operatein pulse-limited mode.

k m R

F or

H cY solut ion R H

cY

Y H c

H c H

H c

Y H c

H

c H R

Y H R

7.1

ns3.3 km,800H

22Re

)2

(

2

2

2

2222

22

2

222

!

!!

!!!}

!

!¹ º

¸©ª

¨

!

!

H

XHX

XX

X

X

X




Radar Altimeter

A short pulse radar² Uses pulse compression to obtain fine range

resolution or height measurement.

² Range measurement uncertainty of a pulse radar.

cmr

F or N

S B

c

r

5.3

100S/NMHz,300Bexample

22

s!(

!!

s!(




Radar altimeter

Other sources of errors² Atmospheric delays² Troposheric delays.² EM bias² Pointing errors

² Orbit errors² Accuracies of few cms are

being achieved with newgeneration sensors. Dual-frequency Water vapor³

radiometers

GPS ² orbit determination Calibration.

Resti et al, ³The Envisat Altimeter System RA-2,´ESABulletin 98, June 1999

sigma=5.5 cm




Radar Altimeter³typical system

Resti et al, ³The Envisat Altimeter System RA-2,́ ESA Bulletin 98, June 1999




Radar Altimeter

Waveform analysis² Time delay is measured

very accurately andconverted into

distance.² Spreading of the pulse

is related to SWH.

² Scattering coefficient

can be obtained bydetermining the power.

Resti et al, ³The Envisat Altimeter SystemRA-2,́ ESA Bulletin 98, June 1999




Radar Altimeter- typical system

Block diagram of Envisat RA

Resti et al, ³The Envisat Altimeter System RA-2,́ ESA Bulletin 98, June 1999




Active sensors

Scatterometer² Scatter o Meter ² A calibrated radar used to

measure scattering coefficient.² They are used to measure radar backscatter as a

function of incidence angle.² Ground and aircraft-based scatterometers arewidely used.

² Experimental data on variety of targets to support modeland algorithm development activities.

» Developing algorithms for extracting target

characteristics from data.» Understanding the physics of scattering to developempirical or theoretical models.

» Developing target classification algorithms




Active sensors³ Scatterometers

Wide range of applications² Wind vector measurements

² Sea and glacial ice

² Snow extent.

² Vegetation mapping

² Soil moisture

Semi-arid or dry areas.




Microwave Remote Sensing³ Atmosphereand Precipitation

Global precipitation mission² Will consist of a primary spacecraft and a

constellation. Primary Spacecraft

² Dual-frequency radar.

» 14 and 35 GHz.

² Passive Microwave Radiometer

² Constellation Spacecraft Passive Microwave Radiometer



Microwave Remote Sensing³Active

Sensors

Imaging Radars




Imaging Radars & Scatterometers

Imaging Radars Real Aperture Radar (RAR)

Synthetic Aperture Radar (SAR) Widely used for military and civilian

applications.

RAR

Thin long antenna mounted on the side of anaircraft.




Imaging radars

RAR² Resolution is

determined by

antenna beamwidth inthe along trackdirection

² Pulse width in thecross-track direction

RAR geometry

factor weighting!

!!

k

D

Rk Rr

aa

P FH

)sin(2 U

XH

c

r c!




Imaging radars

For a radar operatingat f=10 GHz with a 3-mlong antenna in thealong track directionand 0.5 us pulse,resolution at 45 degreeincidence and range of10 km is given by

Assume k=0.8

m106

)45sin(2

105.0103

8003

03.01000008.0

100

106)45sin(2

105.0103

803

03.0100008.0

68

68

!!

!!

!

!!

!!

x x xr

m

xr

k m R

m

x x xr

m

xr

c

a

c

a

H

H

H

H




Imaging Radars: RAR

ResolutionRARs were used

until 1990s.

They are replaced

by SARs.Resolution should

1/20 about thedimensions of thetarget we want torecognize

MRS: vol. II, Ulaby, Moore and Fung




SAR

Synthetic Aperture Radar Use the forward motion of an aircraft or a

spacecraft to synthesize a long antenna. Satellite SARs

ERS-1, ERS-2, RADARSAT, ENVISAT, JERS-1,SEASAT, SIR-A,B& C. Applications

Ocean wave imaging Oil slick monitoring Sea ice classification and dynamics

Soil moisture Vegetation Glacial ice surface velocity




SAR

We can use a small physical antenna

For focused SAR resolution is

independent of Wavelength

Range

Best possible resolution is L/2 Where L= length of the physical antenna




RF Spectrum

Microwave Radiometry covers a range of frequencies.

1 GHz 10 GHz 100 GHz 1000 GHz

Soil

Moisture

1-3 GHz

Resolution /

aperture

Atmospheric

Temperature

54, 118 GHz

Accuracy

Atmospheric

Water Vapor

22, 24, 92, 150,

183 GHz

Accuracy

Sea Surface Salinity

1-3 GHz

Receiver sensitivity/

stability

Precipitation

11, 31,37,89 GHz

Frequent global

coverage

Atmospheric

Chemistry

190, 240, 640,

2500 GHz

High frequency

Sea Ice

37 GHz

Polar coverage

Ocean Surface Wind

19, 22 GHz

Polarimetry

Cloud Ice

325, 448, 643 GHz

High frequency

30 cm 3 cm 3 mm 0.3 mmP

R

L band S band C band X band Ku/K/Ka band Millimeter Submillimeter

Hartley, NASA




Microwave Radiometers³ theory

Planck·s Law of radiation

Where S(,T) =Intensity of

radiation in w/m2 T = temperature in Kelvins h = Planck·s constant, 6.625 ×

10-34 J·s c = velocity of propagation

m/s

k = Boltzmann constant,1.380 × 10-23 J/K

= wavelength, m

1

12),(

5

2

!kT

ch

e

hcT s

PP

TP

4

2),(

Approx

P

TP

P

ckT T S

kT ch

Jean s Ra yl eig h

!




Microwave Radiometer

At microwave frequencies radiationintensity is directly proportional to thetemperature.

For gray bodies² Pa = kT b B² k =Boltzman constant, B = bandwidth, Hz.

² T b = Brightness temperature, K² T b =e T phy

² e = Emissivity of the object or media





Two basic types of radiometers² Total power radiometer

Highest sensitivity

² Switching-type radiometers and its variants.

Typical total power radiometer

K T

K T

s MH z B

t imee g r at ion

band wid th B

where

B

T T

tot al

in

in

in

Tot al

2.0

500

1,6

int

TTTsysaltota

!(

!

!!

!

!

!

!(

X

X

X





Dicke or Switching-type radiometer² Any fluctuations in gain of the receiver will

reduce radiometer sensitivity.

² To eliminate system effects, Dickedeveloped switching type radiometer. It consists of switch and a synchronous

detector. The input is switched between theantenna and noise source. If the injected noisepower is equal to input signal power, the effectof gain fluctuations is eliminated.





Typical Dicke-type radiometer

in BXH total1.4TT

50% byreducedisn timeintegratio 50%,iscycledutytheIf

!




RF Radiometry Characteristics

Moden Radiometer

Digital processor

To eliminate down conversion process

digitalprocessor/

correlator

scan

low noise

amplifier

multiplexer/

spectrometer

detector/

digitizer mixer

LO

Receiver

Antenna

Hartley, NASA





Research and application ofmicrowave technology to remote

sensing of² Oceans and ice

² Solid earth and Natural hazards..

² Atmosphere and precipitation.² Vegetation and Soil moisture




Microwave Remote Sensing³ Ocean andIce

Winds

² Scatterometer.

Quickscat, Seawinds

² Polarimetric radiometer

Ocean topography² Radar altimeters

Ocean salinity

² AQUARIUS

Radiometer and radar combination.

² Radar to measure winds for correcting for the effectof surface roughness.




Ocean Vector Winds² Scatterometers

QuikScat Replacement mission for NSCAT, following loss of ADEOS Launch date: June 19, 1999SeaWinds

EOS instrument flying on the Japanese ADEOS II Mission

Launch date: December 14, 2002 ????Instrument Characteristics of QuikScat and SeaWinds Instrument with 120 W peak (30% duty) transmitter at 13.4

GHz, 1 m near-circular antenna with two beams at 46o and 54o

incidence angles

Scatterometers send microwave pulses to the

Earth's surface, and measure the power scattered

back. Backscattered power over the oceans

depends on the surface roughness, which in turn

depends on wind speed and direction.

QuikScat

SeaWinds

Advanced sensors± larger aperture

antennas.Passive polarimetric sensors.

Courtesy: Yunjin Kim, JPL

Ocean Topography Missions




Ocean Topography Missions

TOPEX/Poseidon and Jason-1

Joint NASA-CNES Program ± TOPEX/Poseidon launched on August 10, 1992

± Jason-1 launched on December 7, 2001

Instrument Characteristics

± Ku-band, C-band dual frequency altimeter

± Microwave radiometer to measure water vapor

± GPS, DORIS, and laser reflector for precise orbit determination

Sea-level measurement accuracy is 4.2 cm

TOPEX/Poseidon & Jason-1 tandem mission for high resolution oceantopography measurements

TO P EX/ P oseid on Ocean to po g r a ph y

o f the P acific Ocean dur ing E l Niño

and La Niña.

The most effective measurement of ocean currents

from space is ocean topography, the height of the sea

surface above a surface of uniform gravity, the geoid.

T he priority is to continue the measurement

with TOPEX/P oseidon accuracy

on a long-term basis for climate studies.


Ocean Surface Topography Mission




Ocean Surface Topography Mission An Ex perimental Wide-Swath Altimeter

By adding an interferometric radar system to a conventional radar altimeter

system, a swath of 200 km can be achieved, and eddies can be monitored over

most of the oceans every 10 days. The design of such a system has

progressed, funded by NASA¶s Instrument Incubator Program. This

experiment is proposed to the next mission, OSTM (Ocean Surface

Topography Mission)

South AmericaCourtesy: Yunjin Kim, JPL

Global Ocean Salinity




Global Ocean Salinity

Aquarius (JPL, GSFC, CONAE)

ESSP-3 mission in the riskmitigation phase

First instrument to measure g lobal

ocean salinity

± Passive and active microwaveinstrument at L-band

± Resolution

Baseline 100km, Minimum200km

± Global coverage in 8 days

± Accuracy: 0.2 psu

± Baseline mission life: 3

years

1 week of salinity measurements from space

100 yrs of salinity measurements by shipCourtesy: Yunjin Kim, JPL




SRTM (Shuttle Radar Topography Mission)

C-band single pass interferometric SAR for

topographic measurements using a 60m

mast

DEM of 80% of the Earth¶s surface in a

single 11 day shuttle flight

± 60 degrees north and 56 degrees southlatitude

± 57 degrees inclination

225 km swath

WGS84 ellipsoid datum

JPL/NASA will deliver all the processed data

to NIMA by January 2003

Absolute accuracy requirements

± 20 m hori zontal

± 16 m vertical

The current best estimate of the SRTM

accuracy is

10 m horizontal and 8 m vertical

P artnership between N AS A and NIM A

(National Imag ery and Mapping Ag ency) X -band from German and Italian space

ag encies


L band InSAR Technolog




L-band InSAR Technology

InSAR velocity difference indicates a 10%

increase in ice flow velocity from 1996 to

2000 on Pine Island Glacier

[Rignot et al., 2001]

Surface deformation due to Hector Mine

Earthquake using repeat-pass InSAR data

Interferometric Synthetic Aperture Radar

(InSAR) can measure surface

deformation (mm-cm scale) through

repeated observations of an area

L-band is preferable due to longer

correlation time due to longer

wavelength (24cm)

Solid Earth Science Working Group

recommended that

In the next 5 years, the new space

mission of highest priority for solid-

Earth science is a satellite

dedicated to InSAR measurementsof the land surface at L-band




Microwave Remote Sensing² Soil

Moisture.

HRDROS² Back-up ESSP mission for global soil moisture. L-band radiometer.

L-band radar.

- 98 .5 - 98 .0 - 97 .5

35.0

35.5

36.0

36.5

- 98 .0 - 97. 5 - 97 .0

0

10

20

30

40

50

Southern Great Plains Hydrology Experiment (SGP97)Surface Soil Moisture Derived From Remotely Sensed Microwave Data

June 30 July 1

July 2 July 3

Soil Moisture (%)

L a t i t u d e ( D e g r e e s )

Longitude (Degrees)

50

40

30

20

10

0

35.0

35.5

36.0

36.5

37.0

Chickasha

ElReno

Lamont

OklahomaCity

Chickasha

ElReno

Lamont

OklahomaCity

Chickasha

ElReno

Lamont

OklahomaCity

Chickasha

ElReno

Lamont

OklahomaCity

June 30

NASA LandSurface Hydrology Program

- 98 .5 - 98 .0 - 97 .5

35.0

35.5

36.0

36.5

- 98 .0 - 97. 5 - 97 .0

0

10

20

30

40

50

Southern Great Plains Hydrology Experiment (SGP97)Surface Soil Moisture Derived From Remotely Sensed Microwave Data

June 30 July 1

July 2 July 3

Soil Moisture (%)

L a t i t u d e ( D e g r e e s )

Longitude (Degrees)

50

40

30

20

10

0

35.0

35.5

36.0

36.5

37.0

Chickasha

ElReno

Lamont

OklahomaCity

Chickasha

ElReno

Lamont

OklahomaCity

Chickasha

ElReno

Lamont

OklahomaCity

Chickasha

ElReno

Lamont

OklahomaCity

June 30

NASA LandSurface Hydrology Program

Courtesy: Tom Jackson, USDA

SGP¶97

Radar

Pol: VV, HH & HV

Res ± 3 and 10 km

Radiometer

Pol: H, V

Res =40 km,

dT= 0.64º K




Salient Features

N AS A E SSP mi ssion

First 94 GH z r ad ar s pace bor ne s y stem

C o-manif ested with C A LIPS O on Del t a l aunch vehicl e

Flies F or mat ion with the EOS C on stell at ion

Current l aunch d ate: A pr il 2004

O per at ional lif e: 2 years

P art nership with DoD ( on-or bit o p s), DoE ( valid at ion ) and CS A ( r ad ar d evel o pment)

Science

Mea sure the vert ical str uct ure o f cl oud s and quant ify their ice and water content

I m prove weather predict ion and cl ar ify climat ic processes.

I m prove cl oud inf or mat ion f rom other satellite s y stem s, in part icul ar those o f Aqua

Invest ig ate the wa y aerosol s a ff ect cl oud s and precipit at ion

Invest ig ate the ut ilit y o f 94 GH z r ad ar to ob serve and quant ify precipit at ion , in the conte xt o f cl oud pro pert ies, f rom s pace

CloudSAT

Microwave Remote Sensing² Atmosphere and

Precipitation





Earth Science and RF Radiometery

Microwave

Radiometry

Applications.

Ocean surface wind

Soil moisture

Sea surface temperature/

Sea surface salinity

Atmospheric temperature, humidity, and clouds

Precipitation

Atmospheric chemistry

Hartley, NASA




Conclusions

A brief overview of microwave remotesensing principles and applications.

Opportunities for research andeducation.² Science

² Technology




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