Algorithm Development GCOM-W AMSR-2 Ocean Product Suite

Transcription

1 Algorithm Development GCOM-W AMSR-2 Ocean Product Suite Joint PI Workshop of Global Environment Observation Mission Otemachi, Tokyo, Japan December 6-9, 2010 Chelle Gentemann Marty Brewer Kyle Hilburn Frank Wentz

2 AMSR Version 7 RSS Version 7 is due out soon improvements to algorithms SST Validation SST v. wind speed SST v. water vapor Improvements to RFI flagging

3 AMSR-E SST Validation SST Comparisons to: Drifting buoys (0.5 m depth) Diurnal warming: Yes Reynolds v2 OI SST. Independent SST derived from AVHRR SSTs, drifting buoys, moored buoys, and ship SST observations Weekly, smooth, low resolution Diurnal warming: Effectively No

4 AMSR-E SST Validation Using Buoys Updated twice daily Figures show last 50 days bias/std & locations of previous day collocations Complete collocated dataset available

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8 } 1 mm AMSR-E.5 m buoys Reynolds OI (foundation SST)

9 AMSRE SST & Wind Speed

10 AMSRE SSTs & Water Vapor Low water vapor = warm bias in AMSRE SSTs corrected in RSS AMSR-E version 7

11 AMSR-E minus drifting buoys 8+ years of colocations ( ) known AMSR-E RFI excluded before comparison North Atlantic cold bias descending passes only => undetected RFI!

12 RFI, RFI, RFI RFI is fastest growing source of errors in ocean suite Primarily SST and wind Also vapor, cloud, rain Identify and flag each source growing complicated New methodologies Brightness Temps Ocean Retrievals

13 RFI and Sea Ice Detection Observed TBs -> geophysical retrievals -> RTM -> predicted TBs

14 Conclusion: Bandwidth Filter AMSR-2 on GCOM-W1 (2011) Bandwidth GHz AMSR-3 on GCOM-W2 (2015) May also 18.7 GHz???

15 Bandwidth Filter AMSR-2 on GCOM-W1 (2011) Bandwidth GHz AMSR-3 on GCOM-W2 (2015) May also 18.7 GHz???

16 Bandwidth Filter Measure Sub Bands? AMSR-2 on GCOM-W1 (2011) Bandwidth GHz AMSR-3 on GCOM-W2 (2015) May also 18.7 GHz???

17 Sub Bands SMAP: 16 Sub Bands (sixteen)

18 Protected Bands 6.9 GHz None? GHz global protection (for radio astronomy) local (threat of aeronautical mobile) 18.7 GHz None? PM EO requirements differ from Radio Astronomy AMSR-E integration time = 2.5 miliseconds Global Coverage

19 RFI ground / ship based Ascension Island, Hawaii, Netherlands, etc. GeoStationary Satellites Media Broadcasts (TV, Radio) Power Direction Frequency *Glint Angle* A.K.A. RFI Angle

20 Geostationary GHz Astra: 19.2 East Longitude ( RFI from 19 not obvious in eastern Mediterranean; highly consistent with power images shown here. ) Hotbird: 13.0 East Longitude Astra: 19.2 E Hotbird: 13.0 E

21 AMSR-E GeoStationary Glint Angles: 10

22 AMSR-E GeoStationary Glint Angles: 15

23 AMSR-E GeoStationary Glint Angles: 20

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30 Ascending passes AMSR-E L2A:Geostationary_Satellite_Glint_Angle Typical day of AMSR-E: 1:30 PM (daytime passes) RFI glint angles from: Hotbird, Astra and DirecTV

31 Satellite TV

32 Ocean Products SST Very Low X X X X X SST Low Res X X X X

33 Ocean Products SST Very Low X X X X X SST Low Res X X X X Wind Low Res X X X X Wind Med Res X X X

34 Ocean Products SST Very Low X X X X X SST Low Res X X X X Wind Low Res X X X X Wind Med Res X X X Water Vapor X X X Cloud Liquid X X X Rain Rate X X X

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37 10.65 GHz RFI / AMSR-E / Europe SST low res (11 GHz +) Wind med res (18 GHz +) SST very low (7 GHz +) Wind low res (11 GHz +)

38 SST RFI Maps No RFI Filters Applied SST Low Res SST Very Low Res Yearly Averages AMSR-E Mission Years 1 7 Descending Passes Geostationary -> Northern Hemisphere

39 AMSR-E Year 1

40 AMSR-E Year 2

41 AMSR-E Year 3

42 AMSR-E Year 4

43 AMSR-E Year 5

44 AMSR-E Year 6

45 AMSR-E Year 7

46 AMSR-E Year 1 AMSR-E Year 7 AMSR-E Year 7

47 AMSR-E Year 7

48 AMSR-E Year 7 Wind RFI

49 AMSR-E Year 7 Wind RFI

50 AMSR-E Year 7 Wind RFI

51 SST RFI Maps No RFI Filters Applied SST Low Res SST Very Low Res Yearly Averages AMSR-E Mission Years 1 7 Ascending Passes Geostationary -> Southern Hemisphere

52 AMSR-E Year 1

53 AMSR-E Year 2

54 AMSR-E Year 3

55 AMSR-E Year 4

56 AMSR-E Year 5

57 AMSR-E Year 6

58 AMSR-E Year 7

59 Old Version (~2005) Outdated RFI Glint angle (17 in North Sea) RFI increasing (power, freq, sources?)

60 NO RFI Filter AMSR-E 2009-April

61 Filter All RFI angles < 25 (heavy data loss) AMSR-E 2009-April

62 Filter All RFI angles < 25 (heavy data loss) Atlantic Bird 7.2 W AMSR-E 2009-April

63 Filter All RFI angles < 25 (heavy data loss) AMSR-E 2009-April

64 V04 RFI angles vary regionally Atlantic Bird 4A filtered Ground sources filtered AMSR-E 2009-April

65 WindSat-NRL Ascending view of Sky Brazil and EutelSat W2A Data image courstesy of: Ian Stuart Adams / Michael H. Bettenhausen / Li Li / Peter W. Gaiser Remote Sensing Division / Naval Research Laboratory / Washington, DC

66 AMSR-E \ asc \ 2009 Q4 (OND)

67 AMSR-E \ asc \ 2010 Q1 (JFM)

68 AMSR-E \ asc \ 2010 Q2 (AMJ)

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70 Eutelsat 10.0 E

71 WindSat-NRL / Decending / 2003 Data image courstesy of: Ian Stuart Adams / Michael H. Bettenhausen / Li Li / Peter W. Gaiser Remote Sensing Division / Naval Research Laboratory / Washington, DC

72 WindSat-NRL / Decending / 2009 Data image courstesy of: Ian Stuart Adams / Michael H. Bettenhausen / Li Li / Peter W. Gaiser Remote Sensing Division / Naval Research Laboratory / Washington, DC

73 AMSR-E WindSat-NRL / Decending / Poster image courstesy of: Ian Stuart Adams / Michael H. Bettenhausen / Li Li / Peter W. Gaiser Remote Sensing Division / Naval Research Laboratory / Washington, DC

74 Satellite TV Out at sea? fully stabilized marine satellite TV systems, brings you digital satellite TV entertainment, including HDTV, whether you re at anchor or offshore (NOT Seen in AMSR-E (yet))

75 Challenges RFI can be strong compared to Earth s passive emissions 10 K common Correction very difficult compared to, for example: 2 K lunar contamination in cold mirror 5 K swath edge contamination RFI contaminated data flagged and removed So far no corrections attempted Fairly easy to identify and flag strong RFI Even easier to overflag and lose good data Weak RFI difficult to detect Not bad for some applications (NRT, weather, ) Not good for climate data records

76 Moving Target RFI is changing constantly Ground sources often sporadic / intermittent Geostationary glint angles are easy, but: New satellites are launched Satellites are launched with reserve capacity» New transponder beams serving new markets» New frequency channels come online anytime Should RFI be filtered: Consistently across time span of dataset? As needed to remove growing RFI?

77 Negative Impacts on Data 6.9 GHz SST (very low res) GHz SST Wind (low res) 18.7 GHz SST (mostly in cold waters) Wind Vapor, cloud, rain: Effect is more subtle, but causing much data loss Throwing out much good data with filter

78 Negative Impacts on Data SSTs, especially in Mediterranean and North Sea AMSR-E nighttime (1:30 AM) passes heavily impacted Diurnal Warming Studies impacted Foundation SSTs impacted Trend Studies RFI may cause spurious trends Trends should be examined regionally

79 Temperature Trends Oxygen channels (MSU GHz) safe from RFI??? Collision avoidance systems in development?

80 Geostationary RFI - Prevention / Mitigation Take / Buy back frequencies near protected bandwidth Broadcast compression can do more with less Cluster geostationary satellites to minimize impact Many spaced evenly over globe, some clustered (DirecTV) Yaw to face poles (4x/day; 160 times more often than TRMM) Forward and rear look (like WindSat) Keep observation bandwidth narrow example: WindSat wider than 18.7 GHz Avoid trending wider; evaluate making narrower Bandwidth Filters: keep the edge out Work with it: Adaptive Algorithms

81 Bandwidth Filter AMSR-2 on GCOM-W1 (2011) Bandwidth GHz AMSR-3 on GCOM-W2 (2015) May also 18.7 GHz???

82 Bandwidth Filter Sub Bands? AMSR-2 on GCOM-W1 (2011) Bandwidth GHz AMSR-3 on GCOM-W2 (2015) May also 18.7 GHz???

83 Sub Bands SMAP: 16 Sub Bands (sixteen)

84 Algorithm Development GCOM-W AMSR-2 Ocean Product Suite Joint PI Workshop of Global Environment Observation Mission Otemachi, Tokyo, Japan December 6-9, 2010 Chelle Gentemann Marty Brewer Kyle Hilburn Frank Wentz Arigato gozai mas