MODISandVIIRSData
EnvironmentalApplica8ons:Part2
KathleenStrabala
UPRDirectBroadcastPolarOrbiter
Workshop
27August2016
Avia8onApplica8ons
Turbulence,Clouds
AtmosphericTurbulence
AtmosphericTurbulence
Whyis6.7μmImportantforthe
Detec8onofTurbulence?
WhyisThisImportant?
MountainWaveCloudsinClearAir
MODIS and
GOES
08:57 UTC
22 June 2009
TurbulenceNotJustfromOrography
MODIS 6.7 µm
Water Vapor
Band
04:18 UTC
10 June 2009
Whyis6.7μmImportantforthe
Detec8onofTurbulence?
CloudApplica8onsCon8nued
•  Clouds
–  Composi8on
–  CloudTopProper8es
–  CloudPhase
Clouds
•  MOD06CloudProduct
Examplefilename:a1.13214.2325.mod06ct.hdf
–  CloudTopProper8esat5km
•  CloudTopPressure,CloudTopTemperature,Cloud
Frac8on,CloudEmissivity
–  CloudPhaseat5km
–  CloudOp8calProper8esat1km(Day8meonly)
•  CloudEffec8veRadius
•  CloudOp8calThickness
CloudTopPropertyAlgorithm
•  CloudTopPressure,Temperature,Emissivity
derivedusingCO2“slicing”
•  MODISproductu8lizes4spectralchannelsin
the13–14µmregion.
•  5x51kmpixelretrievalswhereatleast5of
the1kmpixelsarecloudyasdeterminedby
thecloudmask
•  Cloudproper8esretrievedbothdayandnight
CO2channelsseetodifferentlevelsintheatmosphere
14.2um13.9um13.6um13.3um
ExampleCloudTopPressureProduct
ExampleCloudTopPressureProduct
CloudPhase
•  IRBrightnessTemperatureDifferenceProduct
–  Band29(8.6μm)–Band31(11μm)
–  Takesadvantageofdifferenceinwater/icecloud
absorp8oninthisspectralregion
•  NearInfraredBands(1.6and2.1μm)
ImaginaryIndexofRefrac8onofIceandWater8–13microns
ExampleofUseofTwoIRThermalBands
TropicalStormErika2015
24
25
ExampleofUseofTwoIRThermalBands
TropicalStormErika2015
MODIS
11micron
Brightness
Temperatures
26
ExampleofUseofTwoIRThermalBands
TropicalStormErika2015
8
4
o
8-11micronBrightnessTemperatures
B11micronBrightnessTemperatures
27
ExampleofUseofTwoIRThermalBands
TropicalStormErika2015
MODIS
11micron
Brightness
Temperatures
28
ExampleofUseofTwoIRThermalBands
HurricaneEmily2015
MODIS
11micron
Brightness
Temperatures
ExampleCloudPhaseProduct
ExampleCloudTopPressureProduct
UsingSatelliteImagerytoHelpDiagnoseAreas
ofAircraeIcingPoten8al
GOES IR window animation
17 October 2008
SeaSurfaceTemperatures
SeaSurfaceTemperatures
IMAPPMODIS(a1.yyddd.hhmm.mod28.hdf)
SeaDASfiles(VIIRSandMODIS)(seadasinthefilename)
•  SimpleBrightnessTemperatureDifferenceAlgorithm
•  “SplitWindow”technique
•  Regressionbetween
–  11-12μmBTDIF(MODISbands31and32)
(VIIRSbands15and16)
–  3.7-4.0μmBTDIF(MODISbands20and22)
(VIIRSbands12and13)
•  Mustbecarefulinsunglintregionsbecauseofsolarcontamina8on
–  Inessence,youaretryingtocorrectfortheloweringofthe
observedbrightnesstemperaturesbywatervaporusingthe
BTDIFbetweenthesetwowindowchannels
MODISLongwaveInfraredSeaSurfaceTemperature(c5)
dBT<=0.5
sst=a00+a01*BT11+a02*dBT*bsst+a03*dBT*(1.0/mu-1.0)
dBT>=0.9
sst=a10+a11*BT11+a12*dBT*bsst+a13*dBT*(1.0/mu-1.0)
0.5<dBt<0.9
sstlo=a00+a01*BT11+a02*dBT*bsst+a03*dBT*(1.0/mu-1.0)
ssthi=a10+a11*BT11+a12*dBT*bsst+a13*dBT*(1.0/mu-1.0)
sst=sstlo+(dBT-0.5)/(0.9-0.5)*(ssthi-sstlo)
where:
dBT=BT11-BT12
BT11=brightnesstemperatureat11um,indeg-C
BT12=brightnesstemperatureat12um,indeg-C
bsst=Eithersst4(ifvalid)orsstref(fromReynoldsOISST)
mu=cosineofsensorzenithangle
a00,a01,a02,a03,a10,a11,a12,a13derivedfrommatch-ups
Aqua MODIS Sea Surface Temperature, April 2004
MODIS Sea Surface Temperature used by
Forecasters
AREAFORECASTDISCUSSION...UPDATED
NATIONALWEATHERSERVICEMILWAUKEE/SULLIVANWI
338AMCDTTUEMAY312011
UPDATEDTOADDTODAY/TONIGHTANDAVIATION/MARINE
SECTIONS
.MARINE...CLEARMODISIMAGEFROMMONDAYEARLYAFTN
SHOWEDSHALLOWERNEARSHOREWATERSHADWARMEDINTO
THELOWER50S...WHILEMIDLAKETEMPSREMAINEDINTHEMID
40SDUETOOVERTURNING.TIGHTENINGPRESSGRADIENTTHIS
MORNINGANDSUNSHINEWILLRESULTINSTRONGMIXING
EARLYTHISMRNG.HENCEWLBUMPUPSTARTOFSMALLCRAFT
ADVYSEVERALHOURS...ANDRUNINTOTHEEVE.FEWGUSTS
NEARTHESHOREMAYREACH30-35KNOTSLATERTHISMRNG/
EARLYAFTN.
MODISandVIIRSDBLandProducts
MODISLandSurfaceTemperatures
a1.yyddd.hhss.lst.hdf
LSTTechnique
•  UsesSplitWindow11-12micronBrightness
Temperaturedifferencetocorrectforwater
vapor
•  Moredifficultoverlandbecauseofemissivity
differences
•  MODIS1kmproduct–notwaterorcloud
cleared
•  VIIRSproduct750mM-Bandresolu8on
•  VLSTO*.h5
LandSurfaceTemperatureImage
MODISLSTandbuggers
Reference: X. Porcasi, , S. S. Catala, H. Hrellac, M. C. Scavuzzo, D.
E. Gorla, 2006: Infestation of Rural Houses by Triatoma Infestans
(Hemiptera: Reduviidae) in Southern Area of Gran Chaco in Argentina,
J. Med. Entomol. 43(5): 1060-1067.
Vegeta8onIndices
•  SimpleMODISNDVIproducts1kmproducts
–  a1.16105.1726.ndvi.1000.(500,250)m.hdf
–  Createdfromcorrectedreflectances(removing
Rayleighscarering–atmospheremolecular
scarering)
•  VIIRSNDVI
–  Vegeta8onIndices(NDVIandEVI)750mproducts
•  VIVIO*.h5
Vegeta8onIndex
Normalized Difference Vegetation Index (NDVI) image of Central Africa
http://rapidfire.sci.gsfc.nasa.gov/
Photo-Chemistry
l
Lightmaybeabsorbedandpar8cipate(drive)achemicalreac8on.Example:
Photosynthesisinplants
6CO2 + 6H 2O + hν → C6 H12O6 + 6O2
l
l
l
Onlycertainwavelengthsareabsorbedbysomepar8cipant(s)inthereac8on
Somestructuremustbepresenttoallowthereac8ontooccur–Chlorophyll
Combina8onofchemicalandstructuralproper8esofplants
Primaryandsecondaryabsorbersin
plants
•  Primary
–  Chlorophyll-a
–  Chlorophyll-b
•  Secondary
–  Carotenoids
–  Phycobilins
–  Anthocyanins
Absorp8onofVisibleLight
byPhoto-pigments
Sunlight
Intensity
Chlorophyll b
Absorption
Phycocyanin
B-Carotene
Chlorophyll a
300
400
500
600
Wavelength [nm]
700
800
Lehninger, Nelson and Cox
Theore8caldescrip8on
VISIBLE radiation is highly absorbed
by vegetation in the red (0.68 micron)
and in the blue (0.47 micron). The
absorption is mainly due to
photosynthetically active pigments
NIR radiation is reflected
and transmitted with very
little absorption by vegetation
Contrast between RED and NIR
responses is correlated to
vegetation amount
Soilandcropreflectance
0.6
17 Corn
73 Cotton
9 Sunflower
Fractional Reflectance
0.5
27 Soybeans
0.4
25 Potatoes
0.3
43 Soils
0.2
P. S. Thenkabail
R. B. Smith
E. De Pauw
Yale Center for Earth Observation
0.1
0
300
400
500
600
700
800
Wavelength (nm)
900
1000
1100
SimpleRa8o(SR)
•  Itwasthefirstindextobeused(Jordan,1969)
•  Definedasthera8oXnir/Xred
•  FordenselyvegetatedareasXredtendsto0andSR
increaseswithoutbounds
NormalizedDifferenceVegeta8onIndex(NDVI)
Definedasthera8o
(X.86–X.65)/(X.86+X.65)
Correlated with:
Plant Biomass
Crop Yield
Plant Nitrogen
Plant Dhlorophyll
Water Stress
Plant Diseases
Insect Damage
Applications:
Vegetation
Monitoring
Agricultural
Activities
Drought studies
Landcover Change
Public Health
Climate Change
Issues (mosquitos) Detection
Net Primary
Production
Carbon Balance
RGBandNDVIproduct
Inputs and Processing Chain for
MODIS VI Production
Level1B,
Geolocation
Cloud
Masking
Atmospheric
Correction MOD09
Selection of pixels
to be included
in 16 day
Composite- BRDF
VI
Equation
UsingMODISSunGlintParerns
•  Whatissunglint?
•  Applica8on
–  Iden8fyingregionsofcalmwaters
–  Rela8onshipofcalmwatersandseasurface
temperatures
Sun Glint
Simple example where your
eye is the sensor
Sun Glint Ellipse Defined by: θr < 36
cos θr = sin θv cos θs cos ΔΦ + sin θv
cos θs
Where θv = Viewing Zenith Angle
θs = Solar Zenith Angle
ΔΦ = Relative Angle –
difference between the Solar and
Viewing
azimuth angles.
AquaMODISSunGlintExample
7January2009
SunGlintParerns
MODISBand1
Reflectances
(.65micron)
2016041417:26UTC
MODISTrueColorImage
R:MODISBand1
.65micron
G:MODISBand4
.55micron
B:MODISBand3
.43micron
Relfectances
2016041417:26UTC
ExampleFromLakeMichigan
4June2009
NumericalWeatherPredic8on
Windanalysis18UTC4June2009
MODISSeaSurfaceTemperatures
4June2009
MODISSunglintParern
8June2009
Sun Glint
Simple example where your
eye is the sensor
Sun Glint Ellipse Defined by: θr < 36
cos θr = sin θv cos θs cos ΔΦ + sin θv
cos θs
Where θv = Viewing Zenith Angle
θs = Solar Zenith Angle
ΔΦ = Relative Angle –
difference between the Solar and
Viewing
azimuth angles.