what’s new in modis collection 6 aerosol deep blue products? n. christina hsu, rick hansell, mj...
TRANSCRIPT
![Page 1: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/1.jpg)
What’s new in MODIS Collection 6 Aerosol Deep Blue Products?
N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang,
and Jeremy Warner
Photo taken from Space Shuttle:Fierce dust front over Libya
Laboratory for Atmospheres
NASA Goddard Space Flight Center, Greenbelt, Maryland USA
![Page 2: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/2.jpg)
2
2. Improve Terra/ Aqua surface reflectance estimation ─ Adding dependence of surface reflectance on NDVI
values to detect surface property changes over desert, semi-desert as well urban regions
─ Expanding retrievals into vegetated areas
3. Recover aerosol retrievals over dry regions due to cirrus over-screening using MODIS 1.38 µm band
Changes in MODIS Collection 6 Deep Blue Algorithm
4. Introduce integer QA flags as part of SDS array
1. Extend Terra Deep Blue products beyond 2007 using best calibration corrections
![Page 3: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/3.jpg)
Polarization/RVS Correction C006 Tests:
Deep Blue Aerosol Retrieval Algorithm
MODIS Working Group Meeting
18-20 May 2011
Richard A. Hansell [email protected] (301.614.6132)
Acknowledgements: B. Wenny (Sigma Space Corp), G. Meister (GSFC), B. Franz (GSFC), MCST group, B. Ridgway (SSAI), and J. Kuyper (Sigma Space Corp.).
![Page 4: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/4.jpg)
Outline
• Background– Previous Work/Current Study
• Spatial/Temporal Coverage and L1B Data
• Deep Blue AOT Comparisons– MISR– AERONET
• Summary
![Page 5: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/5.jpg)
Polarization/RVS Corrections(Background)
• Extension of work performed by Jeong et al.2011 (IEEE Trans. Geosci. Remote Sens.)– Study focused on B8 (412 nm) corrections utilizing GSFC’s OBPG cross-
calibration method (Kwiatkowska et al. 2008) using C5.1 L1B Terra data. • Significant improvements found in DB retrieved AOT after corrections. • C5.1 DB AOT products have been re-processed using these procedures for Mar
2000 - Dec 2007. See LAADS archive (http://ladsweb.nascom.nasa.gov/)• For C6, coverage is extended through 2010 using OBPG updated x-cal data.
• Current work assesses performance of B8 corrections using C6 L1B Terra/Aqua MODIS data based on OBPG x-cal and MCST calibration methodologies.– Estimated B3 (466 nm) corrections are also evaluated. B9 /B10 (443/488 nm)
correction factors are wavelength interpolated.
– DB retrieved parameters used for comparisons (AERONET + MISR)
![Page 6: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/6.jpg)
TOA total radiance, It
Im : TOA MODIS measured radiancepc : Polarization correction factor1/M11 : Response-Versus-Scan (RVS)
Slide from Myeong-Jae Jeong’s (MJ) presentation for OBPG & Deep Blue Aerosol Retrieval group at NASA/GSFC June 2009
![Page 7: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/7.jpg)
Spatial/Temporal Coverage + Data
• 29 days spanning Y2000-2010 (Terra) and Y2002-2010 (Aqua) – On average: 2 test days/year
• Geographical domain covers: 20W-60E;0-35N (arid/semi-arid surfaces)
• Apply OBPG corrections (Vicarious calibration method – Kwiatkowska et al. 2008, Appl. Opt.) to B8:– LUT version xcal_modist_txc08a– updates planned this summer
• MCST corrections: Terra (multiple band from EV data 1-4, 8, and 9), and Aqua (8 and 9 from EV data)
Northern Africa
PersianGulf
Baseline MCST
Terra Aqua Terra Aqua
PGE02 v6.1.6_3AS 313
PGE02 v6.1.7_3AS 365
PGE02 v6.1.121
AS 355
v6.1.131
AS 355
![Page 8: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/8.jpg)
MODIS DB VS. MISR AOT
![Page 9: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/9.jpg)
MCST No Corr. B8 B8+B32000
2002
2006
MO
DIS
DB
AO
T
MISR AOT
![Page 10: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/10.jpg)
MCST No Corr. B8 B8+B32007
2010
MO
DIS
DB
AO
T
MISR AOT
![Page 11: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/11.jpg)
MODIS DB vs. AERONET AOT
![Page 12: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/12.jpg)
TERRA, QA=3 ONLY
RUN1–B8 RUN2–B3+B8
RUN3-MCST RUN4-No Corr.
![Page 13: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/13.jpg)
TERRA, All QA
RUN1–B8 RUN2–B3+B8
RUN3-MCST RUN4-No Corr.
![Page 14: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/14.jpg)
AQUA, QA=3 ONLY
No B8 B8
MCST
![Page 15: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/15.jpg)
AQUA, All QA
No B8 B8
MCST
![Page 16: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/16.jpg)
Deep Blue retrieved AOT using MCST and OBPG correction schemes for Terra MODIS reflectance data. Panel (a) mean AOT differences between Terra MODIS DB and MISR.Panel (b) Comparison of mean DB retrieved AOT.
MCST vs. OBPG Band Corrections: Comparisons Using Deep Blue
(a) (b)
![Page 17: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/17.jpg)
2007MCST No Corr.
B8 B3+B8
![Page 18: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/18.jpg)
2009MCST No Corr.
B8 B3+B8
![Page 19: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/19.jpg)
Summary
• Differences between MCST and OBPG calibration methods for C6 are small in terms of DB retrieved parameters.– For given test cases, the performance of
MCST and OBPG schemes is comparable.
• Recommend performing further testing using more extensive L1B datasets before C6 delivery.– Ideally need monthly datasets for select years
to generate adequate statistics.
![Page 20: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/20.jpg)
20
2. Improve Terra/Aqua surface reflectance estimation ─ Adding dependence of surface reflectance on NDVI
values to detect surface property changes over desert, semi-desert as well urban regions
─ Expanding retrievals into vegetated areas
3. Recover aerosol retrievals over dry regions due to cirrus over-screening using MODIS 1.38 µm band
Changes in MODIS Collection 6 Deep Blue Algorithm
4. Introduce integer QA flags as part of SDS array
1. Extend Terra Deep Blue products beyond 2007 using best calibration corrections
![Page 21: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/21.jpg)
21
Cloud-Screened Reflectances
Yes
NoWater Surface?
Yes
Vegetated Surfaces: Hybrid Method
),( 1.249.0 NDVIgs ),( 1.267.0 NDVIfs
NDVI < 0.1No
Aerosol Type
Maximum Likelihood Method
DustDominant
Fine Mode orMixed Aerosols
Dust/Sea Salt Models
Smoke/Sulfate Models
Single-Scattering Albedo
Single-Scattering Albedo
Aerosol Optical Thickness
Aerosol Optical Thickness+ Aerosol Optical
ThicknessAerosol Optical
ThicknessÅngström ExponentÅngström Exponent+
Coarse Modes Fine Modes
Flowchart for Deep Blue Algorithm
Stop
![Page 22: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/22.jpg)
22
Retrieving Aerosol Properties over Vegetated Regions in Collection 6 Deep Blue
![Page 23: What’s new in MODIS Collection 6 Aerosol Deep Blue Products? N. Christina Hsu, Rick Hansell, MJ Jeong, Jingfeng Huang, and Jeremy Warner Photo taken from](https://reader035.vdocuments.mx/reader035/viewer/2022062712/56649c7e5503460f9493341b/html5/thumbnails/23.jpg)
23
Improving Over-Screening of Thin Cirrus in Deep BlueImproving Over-Screening of Thin Cirrus in Deep Blue
NCEP TPW (mm)
AOT C5.1 AOT C6
BTD11-12RR1.38/0.66over Sahara on 2006/03/07