SUBGROUP REPORT

Jeff MorisetteJeffrey.T.Morisette@nasa.gov, (301) 614-6676

GOFC/GOLD Global Geostationary Fire Monitoring

CEOS Working Group on Cal/Val

LAND PRODUCT

LPV outline

• Review of subgroup’s status and goals

• Validation activities

• Conclusions

LPV outline

• Review of subgroup’s status and goals

• Validation activitiesValidation activities

• ConclusionsConclusions

• Established in 2000• Followed Terrain-mapping subgroup as topic-

specific subgroup(non-wavelength-specific)

• Jeff Morisette (NASA) starting as chair in February 2003

• Agreement from Fred Baret (“VALERI, INRA-CSE) to be “chair-elect”= potential chair in 2006)

IGOS-P

GOFC/GOLD and LPV

User accuracyrequirements

IT and Regional networks: local

expertise

GOFC ITs

Informed use of CEOS products

Product evaluation, feedbackValidation protocols

LPV: topical mtgs & product-specific intercomparisons

LPV

WGCV

CEOS Plenary

GOFC/GOLD

GTOS

IGOS

Why validate global land products

• WGCV definition implies validation = “Estimating Uncertainty”

• Good science and resource management require understanding of product accuracy/uncertainty

• Explicit statements of uncertainty fosters an informed user community and improved use of data

• International environmental protocols and agreements imply products may be independently evaluated and possibly challenged

• As more, and similar, global products are produced by CEOS members (via such programs as “GEO”), inter-use will require characterization of each product’s uncertainty

LPV: mission statement & objectives

Mission• To foster quantitative validation of higher-level global land products

derived from remote sensing data and relay results so they are relevant to users

Objectives(a) To work with users to define uncertainty objectives(b) To identify and support global test sites for both systematic and

episodic measurements (WGCV / WGISS Test Facility)(c) To identify opportunities for coordination and collaboration(d) To develop consensus “best practice” protocols for data collection

and description(e) To develop procedures for validation, data exchange and

management (with WGISS)

Big Picture

LPV provides a validation service to the Integrated Global Observation Strategy’s Global Terrestrial Observation System.

Implications:– Focus Products: Biophysical, Land Cover, & Fire– Working in conjunction with GOFC/GOLD’s regional

networks– Need to integrate with TEMS & GT-Net

Current/Upcoming Topical workshops

• Follow-up Land Cover/Changeaiming toward “best practices” documentEarly 2004, Boston University, USA

• Fire and Burn scar:Global Geostationary Fire Monitoring ApplicationsA Joint GOFC/GOLD Fire and CEOS LVP WorkshopMarch 23-25, 2004, EUMETSAT, Darmstadt, Germany(related to Action WGCV 20-8)

• “Results” workshop for LAI-intercomparison fruition of LAI-intercomparison 16 August 2004, University of Montana, Missoula US

• Surface Reflectance and Albedo/BRDF ? in conjunction with next BSRN meeting

Five listservs establishedceos_lpv_gen@listserv.gsfc.nasa.govGeneral information regarding LPV activity, both scientific and administrative

ceos_lpv_rad@listserv.gsfc.nasa.govsurface RADiation products, including surface reflectance/atmospheric correction, land surface temperature, albedo and BRDF

ceos_lpv_bio@listserv.gsfc.nasa.govBIOphysical parameters, including vegetation indices, leaf area index, FPAR, and vegetation productivity

ceos_lpv_lc@listserv.gsfc.nasa.govLand Cover and land cover change products

ceos_lpv_fire@listserv.gsfc.nasa.govFIRE, burn scar, and fire emissions products

(related to action WGCV 20-11)

IEEE Transaction on Geoscience and Remote Sensing special issues

Purpose:• Lay out the current suite of higher-level global land

products and quantitatively establish their accuracy.• Provide a user’s perspective on the implications of a

product’s accuracy to understand: – how accurate the product needs to be– why it is important to quantify the uncertainly– how close currently available data come to meeting

those needs

Proposed TGARS special issues

• Open invitation – (suggestions or volunteers for reviews are also

welcome)• Papers due October 2004• Anticipated publication date early 2006• Ultimate objective is to provide not “mandatory

protocols” but an “acceptable standard”

Validation:the process of assessing by independent means

the quality of the data products derived from the system outputs

(LPV will operates under this definition, but also with the understanding that validation activities should:- consider user accuracy needs and- feedback to algorithm improvements.)

CEOS Definition

MODIS validation “hierarchy”

• Stage 1 Validation:  Product accuracy has been estimated using a small number of independent measurements obtained from selected locations and time periods and ground-truth/field program effort.

• Stage 2 Validation: Product accuracy has been assessed over a widely distributed set of locations and time periods via several ground-truth and validation efforts.

• Stage 3 Validation: Product accuracy has been assessed and the uncertainties in the product well established via independent measurements in a systematic and statistically robust way representing global conditions.

Biome Map

• Exhaustive and mutually exclusive global biome map• Close match to GOFC/GOLD regional networks• Published independently of LPV

Gurney et al. (2002) Towards robust regional estimates of CO2 sources and sinks using atmospheric transport models. Nature, 415, 626-630, 7 Feb. 2002.

Accuracy statements

• Should be “user-oriented” and supported with peer-review literature

• Augment validation “stage hierarchy”• Standardize/summarize information for

each product• MODIS land team plans to update CEOS

information for MODIS land products

MODLAND Validation home pagehttp://landval.gsfc.nasa.gov/MODIS

Link to accuracy statement for each product

…page for each product

…pages for supporting materials

• Overall accuracy statement• Link to QA information• List of support material

•Title, author, abstract•Figures/captions•Tables/captions

Example: MODIS accuracy statements

LPV outline

• Review of subgroup’s status and goalsReview of subgroup’s status and goals

• Validation activities

• ConclusionsConclusions

LPV Validation examples

• CEOS “Core Sites”• Leaf Area Index “Intercomparison”• Albedo/BRDF• Active Fire/Burnt Area• Opportunities for Geostationary

CEOS “Core Sites” goals

• Provide a focus for ongoing satellite, aircraft, and ground data collection for validation of CEOS member satellite/sensor products

• Provide scientists with sets of readily accessible in-situ and CEOS member instrument data for algorithm validation and improvement

• Build on infrastructure of existing scientific networks and validation sites

• Realize international cost-sharing opportunities

CEOS “Core Sites” implementation• Utilize existing networks of validation sites for

joint/multiple validation of CEOS member global land product

– EOS Land Validation Core Sites– VALERI Network of sites – GTOS “Terrestrial Ecosystem Monitoring Sites”– CEOP/NASDA, CSIRO, GT-net, ILTERS sites

• Provide easy access to high resolution data and subsets of global land products from CEOS member sensors

• Conducted as a joint project with the CEOS Working Group on Information Systems and Services

CEOS “Core Sites”: Phase 1

• Simple, Web-Based Interface to CEOS Core Sites

• Allow Users to Specify Conversion Parameters

• Provide Access to EO and in-situ Data• Begin With MODIS, SPOT Veg, & Landsat• Allow Reprojecting• Allow Reformatting into GeoTIFF

Subsetting, Reprojection,

Formatting, QCData Catalog

Limited StorageData Tools

Core Test Sites Data Distribution

MODIS Subsets, ETM+, ASTER(EDC DAAC)

SeaWiFS Subsets(GSFC)

MAVT(MERIS,AATSR)

IVOS Data

InvestigatorWGISS Test Facility

In Situ Data (PIs; ORNL)

Science

http://edcsgs16.cr.usgs.gov/wgiss/

User Code = calval99Password = wgiss03

Feedback welcomeJeff Morisette (jeff.morisette@nasa.gov) John Dwyer (dwyer@usgs.gov)

NDVI time series for Harvard Forest LTER

Year: close up 2000 - 2004

NDVI time series for Harvard Forest LTER

Year: close up 2000 - 2004

NDVI time series for Mongu, Zambia

Year: close up 2000 - 2004

“Difference” analysis

Lag

AC

F

0 5 10 15

-0.5

0.0

0.5

1.0

Series : spotlessavhrr[["mongu"]]NDVI SPOT - AVHRR

1981 through 2002Year

Diff

eren

ce in

ND

VI

1998 1999 2000 2001 2002 2003 2004

-0.1

0-0

.05

0.0

0.05

0.10

0.15

0.20

Autocorrelation function

Lag (in months)Years (1998 – 2004)

NDVI Difference: SPOT - AVHRR

Average difference is 0.034 Significant ½ and 1 year lags

LPV Inter-comparisonSite contacts provide “Vital Statistics”

LPV provides subsets of global LAI product(s)

Field campaign(s):

LPV acquires and posts relevant high-res multispectral imagery

Site contacts collect field data and register these in the Mercury system

Site contacts provide Internet link to locally maintained high-resolution LAI surface, with proper documentation on how the surface was derived

LPV posts link to LAI-surface on LAI-intercomparison page

LPV to create link to the site from the LAI-intercomparison page

Data are shared among fellow “LAI-intercomparison” participants for research comparing both validation results and methods

Sites added to this international activity are those that help create a globally

representative sample - across biomes and continents

AND have a strong need or intention to utilize global, coarse resolution, LAI products.

Albedo “Intercomparison”

• Albedo intercomparison is gaining momentum• Discussed at meeting in Fall ’02• Consider are of overlap between MSG and MODIS• Utilize Baseline Surface Radiation Network sites with

Albedometers• MODIS Albedo and Aerosol products subset and

available through Oak Ridge National Lab• Concept will be brought to BSRN at their July meeting

(interaction between Crystal Schaaf, Atsumu Ohmura, and Andreas Roesch)

• “Kick off” will be a joint Working on Cal/Val meeting / Albedo Validation Campaign in Argintina, early 2005

The CEOS “Intercomparison” concept

• LAI will serve as pilot study (August workshop and article in special issue)

• Albedo intercomparison is gaining momentum

• Burnt area intercomparison has strong potential – GBA2000 and MODIS in Africa

“Intercomparison” General Timeline

LAI Albedo Burnt AreaTopical meeting to

establish data requirements

Decide on Sites

Develop data sharing infrastructure

Field Campaigns & individual product analysis

Synthesis of results

MODIS burnt area validation

• Courtesy of David Roy et al., UMd

• Botswana, Okavango Delta, 2001• Landsat ETM+ path 175 row 073

• Cloud-free scenes acquired 32 days apart:– September 4th – October 6th

Landsat ETM+Sept. 4th

Landsat ETM+Oct. 6th

Yellow vectors = ETM+ interpreted burned areas occurring between the two ETM+ acquisitions

MODIS 500mBurnedAreas

Sept. 4to Oct. 6

White vectors = ETM+ interpreted burned areas occurring between the two ETM+ acquisitions

Each point illustrates the proportion of a 5.0*5.0 km cell mapped as burned

Burnt Area: MODIS vs ETM+

ASTER fire counts

Pro

babl

ity M

OD

IS d

etec

tion

0 50 100 150

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Estimated Probabilities from Generalized Linear Model

0 50 100 150

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ASTER fire counts

Pro

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OD

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0 50 100 150 200

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1.0

Estimated Probabilities, fixed effects model, v3 vs v4

0 50 100 150 200

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1.0

ASTER fire counts

Pro

babl

ity M

OD

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etec

tion

0 50 100 150

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Estimated Probabilities from Model 1, MODIS version 3

0 50 100 150

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1.0

GOFC/GOLD Fire implementation team: Active Fire Validation with ASTER

MODIS fire detection: INPE and UMd

ACRE 29 Aug 2003UMd INPE

…probably not an issue of which is best, but rather how to combine. … GOES ABBA fire could be included

MODIS fire detection: Brazil February 2004

0

100

200

300

400

500

600

Terra NonCoincident

TerraCoincident

Aqua NonCoincident

AquaCoincident

INPE

UMD

X = 1.6 1.4 1.5 1.3Y = 1.2 1.1 1.2 1.1

Average pixel size – indication that non-coincident fire are further from NADIR

View Angle dependency

NOAA-12 hot spot detection for Tocantins State – Brazil July-August 2001. (x axis = date dd/m)

0

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1/7

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29/7 5/8

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19/8

26/8

Num

ber o

f Hot

Spo

ts

Curve fitting for regional summaries

Fit curve to fire counts filter for extent of ASTER viewing angle. Then take area under the curve to represent fire counts

0

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Num

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f Hot

Spo

ts

- and fit curve with consideration of “error bars” estimated for near-nadir counts resulting from the ASTER analysis.

Daily Fire counts

Time of Day

Num

ber o

f Hot

spo

tsIf we validate using sun-synchronous, what can we say about the accuracy of a “diurnal curve” – example: adjusting diurnal signal to four (or more) points from sun synchronous data, can we estimate the accuracy of “non-linearitites” between sun-syn. observations

LPV outline

• Review of subgroup’s status and goalsReview of subgroup’s status and goals

• Validation activitiesValidation activities

• Conclusions

Conclusion

• LPV is available to coordinate validation activities

• Burnt area “intercomparison” seems attractive

• Validation of Geostationary products is certainly possible, but somewhat limited