modis snow and sea ice data products at the eosdis nsidc daac dorothy k. hall cryospheric sciences...

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MODIS Snow and Sea Ice Data MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly A. Casey/SSAI Nicolo E. DiGirolamo/SSAI Vincent V. Salomonson/Earth Sciences Directorate Emeritus NASA HQ Data Products Review January 11 – 12, 2006

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Page 1: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

MODIS Snow and Sea Ice Data MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAACProducts at the EOSDIS NSIDC DAAC

Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC

and

George A. Riggs SSAI

Kimberly A. Casey/SSAI Nicolo E. DiGirolamo/SSAI Vincent

V. Salomonson/Earth Sciences Directorate Emeritus

NASA HQ Data Products Review January 11 – 12, 2006

Page 2: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Why are Global Snow Cover and Sea Ice Important?

• Snow cover with its large surface area, up to 46 X 106 km2 in the Northern Hemisphere winter, and its high albedo, is a critical parameter in the Earth’s global energy balance; springtime decreases in N.H. snow cover have been measured

• Snow cover supplies >75% of the water resources for the western United States, and is a key component of the water resources in many mountainous areas of the world

• The large surface area of sea ice and its high albedo are critical to the Earth’s energy balance, and research shows that the N.H. sea ice extent has been decreasing

• Changes in the Earth’s cryosphere must be measured by a variety of sensors and at a variety of different resolutions for observation and modeling studies

• It is also critical to develop products that are accurate and well characterized for creation of climate-data records (CDRs)

Page 3: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Snow Products Data Dependencies

• All higher-level products depend on the swath products• All climate-modeling grid (CMG) global products depend on

the tile products• Other MODIS products use MODIS snow cover product as

input– Land-surface temperature, MOD11– Albedo / BRDF, MCD43

Page 4: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Title (ESDT): MOD10_L2 & MYD10_L2

Description: Terra and Aqua swath snow cover includes fractional (sub pixel) snow cover (FSC) for Collection 5; 500-m resolution

Product algorithm theoretical basis: NDSI and criteria tests for snow detection, regression for FSC, cloud masking from MOD35_L2; heritage: Crane and Anderson, 1984; Tucker et al., 1985; Dozier, 1989

Science need (justification): snow-cover monitoring; improved snow cover in terms of temporal and spatial resolution relative to operational products; improved snow/cloud discrimination; automated algorithm (removes possible inconsistencies introduced by analyst interpretation); critical for creation of higher-level snow products

Quality and accuracy information (cal/val, relative and absolute uncertainty, stability, maturity of algorithm): very mature, very stable, absolute uncertainty 2-10% (depending on land cover & season); relative uncertainty 5-20% (compared with operational products with lower temporal and spatial resolution); the FSC within a pixel can be provided with a mean absolute error of < 0.1 over the entire range of FSC 0.0 - 1.0

Intended or appropriate product use (including any limitations on use): for a detailed look at regional snow cover and fractional snow cover, cloud-cover permitting; often multiple swaths a day available

Science value (use of product for science, papers written, breakthroughs, multidisciplinary use): snow-cover monitoring and creation of higher-level products; see references listed on later slides

Page 5: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

December 14, 2000

MODIS binary snow map (left) and fractional-snow-cover product (right) - 500-

m resolution

After Salomonson & Appel (2003)

ND

CO

SD

NEWY

MT

KS

cloud

Page 6: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Title (ESDT): MOD10_L2 & MYD10_L2

Description: Terra and Aqua swath snow cover includes fractional (sub pixel) snow cover (FSC) for Collection 5; 500-m resolution

Product algorithm theoretical basis: NDSI and criteria tests for snow detection, NDVI for improved mapping in forests; regression for FSC, cloud masking from MOD35_L2; heritage: Crane and Anderson, 1984; Tucker et al., 1985; Dozier, 1989

Science need (justification): snow-cover monitoring; improved snow cover in terms of temporal and spatial resolution relative to operational products; improved snow/cloud discrimination; automated algorithm (removes possible inconsistencies introduced by analyst interpretation); critical for creation of higher-level snow products

Quality and accuracy information (cal/val, relative and absolute uncertainty, stability, maturity of algorithm): very mature, very stable, absolute uncertainty 2-10% (depending on land cover & season); relative uncertainty 5-20% (compared with operational products with lower temporal and spatial resolution); often multiple swaths a day available the FSC within a pixel can be provided with a mean absolute error of <10% over the entire range of FSC from 0.0 - 1.0; Collection 4 cloud shadows may appear as false snow especially during the summer (fixed in Collection 5) causing errors of commission

Intended or appropriate product use (including any limitations on use): for a detailed look, often several times daily, at regional snow cover and fractional snow cover, cloud-cover permitting

Science value (use of product for science, papers written, breakthroughs, multidisciplinary use): snow-cover monitoring and creation of higher-level products; see references listed on later slides

Page 7: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

MODIS true-color image (left - bands 1, 4, 3) and snow map (right)

MOD10_L2: 500-m swath product of California and the western U.S., October 31, 2004

cloud

Page 8: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Title (ESDT): MOD10A1 & MYD10A1

Description: Terra & Aqua snow cover daily tile map on sinusoidal grid, includes snow albedo in Collection 4 and albedo and FSC in Collection 5; 500-m resolution

Product algorithm theoretical basis: see heritage for MOD 10_L2 snow detection; scoring algorithm for observation selection, plus albedo calculation, heritage: Nolin and Stroeve, 1997 & Stroeve and Nolin, 1997

Science need (justification): snow-cover monitoring; snow albedo for energy balance modeling; as compared to operational products, improved snow cover in terms of temporal and spatial resolution & improved snow/cloud discrimination; automated algorithm (removes possible inconsistencies introduced by analyst interpretation)

Quality and accuracy information (cal/val, relative and absolute uncertainty, stability, maturity of algorithm): very mature, very stable, absolute uncertainty 2-10% (depending on land cover & season); relative uncertainty 5-10% (compared with operational products with lower temporal and spatial resolution), with the exception of the snow albedo part of the product which is unvalidated; Collection 4 cloud shadows may appear as false snow especially during the summer (fixed in Collection 5)

Intended or appropriate product use (including any limitations on use): for a detailed look at regional snow cover and fractional snow cover, cloud-cover permitting; for use in regional-scale models

Science value (use of product for science, papers written, breakthroughs, multidisciplinary use): used in hydrological modeling to develop snow-cover depletion curves; model output results show improvement with inclusion on MODIS snow maps; albedo needed for energy-balance modeling; products suitable for creation of a CDR; see references listed on later slides

Page 9: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Title (ESDT): MOD10A2 & MYD10A2

Description: Terra & Aqua snow cover 8-day composite tile map on a sinusoidal grid; 500-m resolution, maximum snow extent for the period

Product algorithm theoretical basis: see MOD10_L2, plus compositing algorithm to map maximum snow cover, see heritage for MOD10A1 and MOD10_L2

Science need (justification): see justification for MOD10A1, plus the following: because of cloudcover, composited data are needed to provide clear views, minimize cloud obscuration of snow-covered areas and for use in developing snow-cover depletion curves during cloudy periods

Quality and accuracy information (cal/val, relative and absolute uncertainty, stability, maturity of algorithm): very mature, very stable, absolute uncertainty 2-10% (depending on land cover and season); uncertainty may be greater than in daily products due to propagation of errors during compositing

Intended or appropriate product use (including any limitations on use): see justification for MOD10A1, plus the following: due to cloudcover, some snow events in the 8-day period may not be mapped

Science value (use of product for science, papers written, breakthroughs, multidisciplinary use): used in hydrological modeling to develop depletion curves; model output results show improvement with inclusion on MODIS snow maps; see references listed on later slides

Page 10: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

White is false snow caused by cloud-shadowed land or by cloud-shadowed cloud that occurred on

any day in the period

Total cumulative snow error is 0.19% for the period. The cloud-

shadow screen in Collection 5 will eliminate most of this type of

error

Percent error in tileSnow error countDay

0.032 1832232

0.0009 50231

0.0744188230

0.0643625229

0.003 146228

0.0007 38227

0.0011 62226

0.02 860225

MOD10A2 8-day snow map product for 12-19 August 2004

Southeastern U.S.

false snow

Page 11: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Title (ESDT): MOD10A2 & MYD10A2

Description: Terra & Aqua snow cover 8-day composite tile map on a sinusoidal grid; 500-m resolution, maximum snow extent for the period

Product algorithm theoretical basis: see MOD10_L2, plus compositing algorithm to map maximum snow cover, see heritage for MOD10A1 and MOD10_L2

Science need (justification): see justification for MOD10A1, plus the following: because of cloudcover, composited data are needed to provide clear views, minimize cloud obscuration of snow-covered areas and for use in developing snow-cover depletion curves during cloudy periods; composited maps are needed because cloudcover often precludes daily mapping of snow cover

Quality and accuracy information (cal/val, relative and absolute uncertainty, stability, maturity of algorithm): very mature, very stable, absolute uncertainty 2-10% (depending on land cover and season); uncertainty may be greater than in daily products due to propagation of errors during compositing

Intended or appropriate product use (including any limitations on use): see justification for MOD10A1, plus: due to cloudcover, some snow events in the 8-day period may not be mapped

Science value (use of product for science, papers written, breakthroughs, multidisciplinary use): used in hydrological modeling to develop snow-cover depletion curves; model output results show improvement with inclusion on MODIS snow maps; see references listed on later slides

Page 12: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

The map on the top illustrates the current year snow conditions while the map on the bottom shows the snow extent for the same 8-day MODIS period from last year

Applications of Applications of MODIS snow data in MODIS snow data in Afghanistan for the Afghanistan for the

Famine Early Famine Early Warning System Warning System

(FEWS)(FEWS)

Courtesy Michael Budde/USGShttp://edcw2ks21.cr.usgs.gov/Afghan/product.php?image=so

Page 13: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Snow Accumulation/Depletion Curves above 2500m for the Basin Outlined in Red

Snow-Cover Depletion Curves are Developed using MODIS 8-day Snow Maps (MOD10A2) for FEWS to provide an indication of amount of seasonal snow

cover for irrigation

Courtesy Michael Budde/USGS

Page 14: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Merged MODIS Snow Cover Extent and AFWA Snow Depth

Daily snow depth values from the Air Force Weather Agency (AFWA) and NOAA are used to create a maximum 8-day snow depth corresponding to the MODIS composite period. These two data sources are then merged to

produce a product that identifies snow depth (AFWA) in terms of the snow extent identified using MODIS. The merged product maintains the spatial resolution of MODIS and provides snow depth measurements.

Courtesy Michael Budde/USGS

Page 15: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Title (ESDT): MOD10C1 & MYD10C1

Description: Terra & Aqua snow cover daily map on climate-modeling grid (lat/lon) including fractional snow cover; 0.05-deg resolution (~5 km at Equator)

Product algorithm theoretical basis: see justification for MOD10A1; heritage: see heritage for MOD 10A1

Science need (justification): see justification for MOD10A1; needed for GCM and other product (e.g., AMSR-E and SeaWinds) validation

Quality and accuracy information (cal/val, relative and absolute uncertainty, stability, maturity of algorithm): very mature, very stable, absolute uncertainty 2-10%; relative uncertainty 5-20%

Intended or appropriate product use (including any limitations on use): for an assessment of snow cover globally, cloud-cover permitting, in a single image

Science value (use of product for science, papers written, breakthroughs, multidisciplinary use): useful in GCM modeling for validation; monitoring global snow extent; see references listed on later slides; suitable for creation of a CDR

Page 16: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

MOD10C1: Daily CMG snow map (0.05º resolution)

April 25, 2004

Percent Snow Cover

cloud

Page 17: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Title (ESDT): MOD10C1 & MYD10C1

Description: Terra & Aqua snow cover daily map on climate-modeling grid (lat/lon) including fractional snow cover; 0.05-deg resolution (~5 km at Equator)

Product algorithm theoretical basis: see justification for MOD10A1; see heritage for MOD 10A1

Science need (justification): see justification for MOD10A1; needed for GCM and other product (e.g., AMSR-E and SeaWinds) validation

Quality and accuracy information (cal/val, relative and absolute uncertainty, stability, maturity of algorithm): very mature, very stable, absolute uncertainty 2-10%; relative uncertainty 5-20%

Intended or appropriate product use (including any limitations on use): for an assessment of snow cover globally, cloud-cover permitting, in a single image

Science value (use of product for science, papers written, breakthroughs, multidisciplinary use): useful in GCM modeling for validation; monitoring global snow extent; see references listed on later slides; suitable for creation of a CDR

Page 18: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Title (ESDT): MOD10C2 & MYD10C2

Description: Snow cover 8-day composite tile map on climate-modeling grid (CMG) (lat/lon) including fractional snow cover; 0.05-deg resolution

Product algorithm theoretical basis: see justification for MOD10A2, plus 8-day compositing and binning algorithm, heritage: see heritage for MOD10A2

Science need (justification): see justification for MOD10A2, plus: composited maps are needed because cloudcover often precludes daily mapping of snow cover

Quality and accuracy information (cal/val, relative and absolute uncertainty, stability, maturity of algorithm): very mature, very stable, absolute uncertainty 2-10%; relative uncertainty 5-20%; uncertainty may be greater than in daily products due to propagation of errors during compositing

Intended or appropriate product use (including any limitations on use): for an assessment of snow cover globally, cloud-cover permitting, in a single image; useful for GCM and other product (e.g., AMSR-E) validation

Science value (use of product for science, papers written, breakthroughs, multidisciplinary use): useful in GCM modeling for validation; monitoring global snow extent; see references listed on later slides

Page 19: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

March 6-13, 2002

MOD10C2: 8-Day Composite CMG snow mapfractional snow cover from 1 - 100% not shown

The 8-day composite CMG maps maximize snow cover and minimize cloud cover for the compositing period

April 6 - 13, 2000

Page 20: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Title (ESDT): MOD10C2 & MYD10C2

Description: Snow cover 8-day composite tile map on climate-modeling grid (CMG) (lat/lon) including fractional snow cover; 0.05-deg resolution

Product algorithm theoretical basis: see justification for MOD10A2, plus 8-day compositing and binning algorithm; see heritage for MOD10A2

Science need (justification): see justification for MOD10A2, plus: composited maps are needed because cloudcover often precludes daily mapping of snow cover

Quality and accuracy information (cal/val, relative and absolute uncertainty, stability, maturity of algorithm): very mature, very stable, absolute uncertainty 2-10%; relative uncertainty 5-20%; uncertainty may be greater than in daily products due to propagation of errors during compositing

Intended or appropriate product use (including any limitations on use): for an assessment of snow cover globally, cloud-cover permitting, in a single image; useful for GCM and other product (e.g., AMSR-E) validation

Science value (use of product for science, papers written, breakthroughs, multidisciplinary use): useful in GCM modeling for validation; monitoring global snow extent; see references listed on later slides

Page 21: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Peer-Reviewed Publications – Snow (MOD10 & MYD10) (in press or 2005)

•Shamir, E. and K.P. Georgakakos, in press: Distributed snow accumulation and ablation modeling in the American River Basin, Remote Sensing of Environment.

•Hall, D.K., G.A. Riggs and V.V. Salomonson, in press : MODIS Snow and Sea Ice Products, Earth Science Satellite Remote Sensing - Volume I: Science and Instruments, J. Qu (ed.), Springer-Verlag Press.

•Mcguire, M., A. Wood, A. Hamlet and D. Lettenmaier, 2005: Use of satellite data for streamflow and reservoir storage forecasts in the Snake River Basin, ID, Journal of Water Resources Planning and Management.

•Tekeli, A.E., Z. Akyurek, A.A. Sorman, A. Sensoy and A.U. Sorman, 2005: Using MODIS snow-cover maps in modeling snowmelt runoff processes in the eastern part of Turkey, Remote Sensing of Environment, 97:216-230.

•Brubaker, K., R. Pinker and E. Deviatova, 2005: Evaluation and comparison of MODIS and IMS snow-cover estimates for the continental U.S. using station data, Journal of Hydrometeorology.

•Zhou, X., H. Xie and J.M.H. Hendrickx, 2005: Statistical evaluation of remotely sensed snow-cover products with constraints from streamflow and SNOTEL measurements, Remote Sensing of Environment, 94:214-231.

•Déry, S., V.V. Salomonson, M. Stieglitz, D.K. Hall and I. Appel, 2005: An approach to using snow areal depletion curves inferred from MODIS and its application to land surface modeling in Alaska, Hydrological Processes, 19:2755-2774.

•Rodell, M. and P. Houser, 2005: Updating a land surface model with MODIS-derived snow cover, Journal of Hydrometeorology, 5:1064-1075.

•Lee, S., A.G. Klein and T.M. Over, 2005: A comparison of MODIS and NOHRSC snow-cover products for simulating streamflow using the Snowmelt Runoff Model, Hydrological Processes, DOI10.1002/hyp.5810.

Page 22: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Peer-Reviewed Publications – Snow (MOD10 & MYD10) (2002-2004)

•Salomonson, V.V. and I. Appel, 2004: Estimating fractional snow cover from MODIS using the normalized difference snow index, Remote Sensing of Environment, 89:351-360.

•Simic, A., R. Fernandes, R. Brown, P. Romanov and W. Park, 2004: Validation of Vegetation, MODIS and GOES+SSM/I snow-cover products over Canada based on surface snow depth observations, Hydrological Processes, 18:1089-1104.

•Dankers, R., and S. De Jong. 2004. Monitoring snow-cover dynamics in Northern Fennoscandia with SPOT VEGETATION images. International Journal of Remote Sensing 25 (15): 2933-2949.

•Drusch, M., D. Vasiljevic, and P. Viterbo. 2004: ECMWF's global snow analysis: Assessment and revision based on satellite observations. Journal of Applied Meteorology 43 (9): 1282-1294.

•Dankers, R. and S. M. De Jong, 2004: Monitoring snow-cover dynamics in Northern Fennoscandia with SPOT VEGETATION images, International Journal of Remote Sensing, 25(15):2933-2949.

•Klein A, Barnett A C (2003) Validation of daily MODIS snow maps of the Upper Rio Grande River Basin for the 2000-2001 snow year. Remote Sensing of Environment 86:162-176.

•Maurer E P, Rhoads J D, Dubayah R O and Lettenmaier D P (2003) Evaluation of the snow-covered area data product from MODIS. Hydrological Processes 17:59-71.

•Klein A G, Stroeve J (2002) Development and validation of a snow albedo algorithm for the MODIS instrument. Annals of Glaciology 34: 45-52.

•Hall, D.K., G.A. Riggs, V.V. Salomonson, N.E. DiGirolamo and K.J. Bayr, 2002: MODIS snow-cover products, Remote Sensing of Environment, 83:181-194.

Page 23: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Selected Non-Peer-Reviewed Publications – Snow (MOD10 & MYD10) (2002-2004)•McGuire, M., A. Wood, Q. Zeng and D. Lettenmaier, 2005: Use of MODIS snow cover imagery for

streamflow and reservoir storage forecasts in the Snake River basin, 85th AMS Annual Meeting (San Diego, Ca.), 19th Conference on Hydrology, January 2005.

•Riggs, G.A., N. DiGirolamo, D.K. Hall, 2005: "Comparison of MODIS Daily Global Fractional Snow Cover Maps at 0.05 and 0.25 Degree Resolutions," Proceedings of the 62nd Eastern Snow Conference, 7-10 June 2005, Waterloo, ON, Canada.

•Hall, D.K., R. Solberg, K.A. Casey, J-G. Winther, 2004: "Comparison of MODIS and SnowStar Snow Maps in Scandinavia," Proceedings of the 61st Eastern Snow Conference, 9-11 June 2004, Portland, ME.

•Riggs, G., and D.K. Hall, 2004: "Snow Mapping with the MODIS Aqua Instrument," Proceedings of the 61st Eastern Snow Conference, 9-11 June 2004, Portland, ME.

•Hall, D.K., J.L. Foster, D.A. Robinson and G.A. Riggs, 2004: Merging the MODIS and RUCL monthly snow-cover records, Proceedings of IGARSS 2004, 20-24 September 2004, Anchorage, AK.

•Riggs, G.A., D. K. Hall & V. V. Salomonson, 2003: MODIS Sea Ice Products User Guide (with updates posted on website in 2006)

•Hall, D.K., V.V. Salomonson, G.A. Riggs and A.G. Klein, 2003: "Snow and ice products from the Moderate Resolution Imaging Spectroradiometer," Proceedings of the ASPRS meeting, 5-9 May 2003, Anchorage, AK.

•Riggs, G.A. and D. K. Hall, 2003: "Reduction of Cloud Obscuration in the MODIS Snow Data Product," Proceedings of the 60th Eastern Snow Conference, 4-6 June 2003, Sherbrooke, Quebec, Canada.

•Bussiéres, N., D. De Séve, and A. Walker. 2002. Evaluation of MODIS snow-cover products over Canadian regions. Proceedings of IGARSS’02, Toronto, Canada, pp. 2302-2304.

Page 24: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Summary of Selected Results from UsersSummary of Selected Results from Users

•MODIS snow products (MOD10A1 & A2) are being used extensively as input to refining a daily SWE model for Afghanistan (M. Budde, written communication)

•USGS is using MOD10A1 & A2 as inputs to Southwest Alaska Network vital-signs monitoring network

•MODIS daily snow products compare well with operational products; MODIS products generally show fewer errors with respect to ground measurements (e.g., SNOTEL)

•Cloud mask as applied to the MODIS standard snow products allows more snow to be mapped, in some areas, than does the NOHRSC product (Mauer et al., 2003)

•MODIS daily snow products agree well with SNOTEL measurements in the Upper Rio Grande river basin (Klein & Barnett, 2003)

•Snow-mapping algorithms that are tuned to a specific area can give better results than the standard MODIS snow-map algorithms which are designed to map snow globally, but results are nearly equal if a regionally-tuned cloud mask and coastline is used (Hall et al., 2004)

•MODIS daily snow products improved output of land surface models (Rodell and Houser, 2005)

•Streamflow forecasts with a 2-week lead time using the VIC hydrologic model were improved by using MODIS snow maps; error reduction of 71% was reported by McGuire et al. (2005)

•Use of MODIS snow products in updating reservoir storage volume forecasts showed that storage forecast errors were reduced (or unchanged) in 74% of the seasonal forecasts as a result of MODIS-updated streamflow forecasts (McGuire et al., 2005)

Page 25: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Title (ESDT): MOD29 & MYD29

Description: Terra and Aqua swath sea ice cover and ice-surface temperature (IST); 1-km resolution

Product algorithm theoretical basis: NDSI-based algorithm for sea ice cover (see MOD10_L2 for heritage), and linear regression for IST, cloud masking from MOD35_L2; heritage: Key and Haefliger, 1992; Key et al., 1997

Science need (justification): provides IST needed by modelers - IST controls snow metamorphosis and melt, rate of sea ice growth and air-sea heat exchange; improved clear-sky sea ice cover in terms of temporal and spatial resolution relative to operational clear-sky products; automated algorithm (removes possible inconsistencies introduced by analyst interpretation); critical for creation of higher-level sea ice products

Quality and accuracy information (cal/val, relative and absolute uncertainty, stability, maturity of algorithm): algorithm very stable; IST uncertainty 1.2 - 1.3 K (winter conditions); some error due to ice/cloud confusion (if MOD35 cloud mask fails to map a cloud, it may be mapped as sea ice)

Intended or appropriate product use (including any limitations on use): for a detailed and global look at sea ice cover and measurement of IST for use in modeling; often multiple swaths a day available; fog (not mapped by cloud mask) affects the IST; cloud obscuration is also a limitation

Science value (use of product for science, papers written, breakthroughs, multidisciplinary use): important for modelers; see reference list on a later slide

Page 26: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Title (ESDT): MOD29P1D & MYD29P1D

Description: Terra and Aqua sea ice cover and ice-surface temperature (IST) during daylight on the EASE-Grid; 1-km resolution, daily tile

Product algorithm theoretical basis: see theoretical basis for MOD29, plus scoring algorithm for observation selection; see heritage for MOD29

Science need (justification): see justification for MOD29

Quality and accuracy information (cal/val, relative and absolute uncertainty, stability, maturity of algorithm): algorithm very stable; IST uncertainty 1.2 - 1.3 K (winter conditions); some error due to ice/cloud confusion propagated from MOD29

Intended or appropriate product use (including any limitations on use): for sea ice extent monitoring, and measurement of IST for use in models

Science value (use of product for science, papers written, breakthroughs, multidisciplinary use): useful for development of an IST CDR; see reference list on a later slide

Page 27: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Title (ESDT): MOD29P1N & MYD29P1N

Description: Terra and Aqua ice-surface temperature (IST) during nighttime on the EASE-Grid - 1-km resolution, daily tile

Product algorithm theoretical basis: see theoretical basis for MOD29; scoring algorithm for observation selection; see heritage for MOD29

Science need (justification): for exploratory investigation of nighttime IST

Quality and accuracy information (cal/val, relative and absolute uncertainty, stability, maturity of algorithm): algorithm very stable; IST uncertainty 1.2 - 1.3 K (winter conditions); some error due to ice/cloud confusion propagated from MOD29; major limitation is that the MOD35 cloud mask does not work very well during the nighttime over sea ice

Intended or appropriate product use (including any limitations on use): for measurement of IST for use in modeling; nighttime cloud mask is a major limitation

Science value (use of product for science, papers written, breakthroughs, multidisciplinary use): N/A

Page 28: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Title (ESDT): MOD29E1D & MYD29E1D

Description: Terra and Aqua sea ice cover and ice-surface temperature (IST) during daylight on the EASE-Grid; 4-km resolution

Product algorithm theoretical basis: see theoretical basis for MOD29; daily compositing and binning algorithm; see heritage for MOD29 and MOD29P1D

Science need (justification): see justification for MOD29P1D

Quality and accuracy information (cal/val, relative and absolute uncertainty, stability, maturity of algorithm): algorithm very stable; IST uncertainty 1.2 - 1.3 K (winter conditions); some error due to ice/cloud confusion propagated from MOD29

Intended or appropriate product use (including any limitations on use): for sea ice monitoring and measurement of IST for use in modeling; for validation of GCMs and other products (e.g., AMSR-E sea ice)

Science value (use of product for science, papers written, breakthroughs, multidisciplinary use): for creation of a CDR; see reference list on a later slide

Page 29: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Daily global 4-km resolution ice extent & IST products - composites from May 15-19, 2000

North Polar View South Polar View

Hall et al. (2004)

MOD29E1D MOD29E1D

cloud

Page 30: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Title (ESDT): MOD29E1D & MYD29E1D

Description: Terra and Aqua sea ice cover and ice-surface temperature (IST) during daylight on the EASE-Grid; 4-km resolution

Product algorithm theoretical basis: see theoretical basis for MOD29; daily compositing and binning algorithm; see heritage for MOD29 and MOD29P1D

Science need (justification): see justification for MOD29P1D, plus this product provides a global view of sea ice during daylight hours

Quality and accuracy information (cal/val, relative and absolute uncertainty, stability, maturity of algorithm): algorithm very stable; IST uncertainty 1.2 - 1.3 K (winter conditions); some error due to ice/cloud confusion propagated from MOD29

Intended or appropriate product use (including any limitations on use): for sea ice monitoring and measurement of IST for use in modeling; for validation of GCMs and other products (e.g., AMSR-E sea ice)

Science value (use of product for science, papers written, breakthroughs, multidisciplinary use): for creation of a CDR; for energy-balance modeling; see reference list on a later slide

Page 31: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Peer-Reviewed Publications – Sea Ice (2004 - present)

Scambos, T., T. Haran and R. Massom, submitted: Validation of AVHRR and MODIS ice surface temperature products using in-situ radiometers, Annals of Glaciology.

Hall, D.K., G.A. Riggs and V.V. Salomonson, in press : MODIS Snow and Sea Ice Products, Earth Science Satellite Remote Sensing - Volume I: Science and Instruments, J. Qu (ed.), Springer-Verlag Press.

Hall, D.K., J. Key, K.A. Casey, G.A. Riggs and D.J. Cavalieri, 2004: Sea ice surface temperature product from MODIS, Transactions on Geoscience and Remote Sensing, 42(5):1076-1087.

Non-Peer-Reviewed Publications – Sea Ice

G. A. Riggs, D. K. Hall & V. V. Salomonson, 2003: MODIS Sea Ice Products User Guide (with updates posted on website in 2006)

G. A. Riggs, D. K. Hall & V. V. Salomonson, 2003: Algorithm Theoretical Basis Document (ATBD) for the MODIS Snow and Sea Ice-Mapping Algorithms (with updates posted on website in 2006)

Page 32: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

ConclusionsConclusions•Algorithm improvements developed for Collection 5 reduce the snow errors of commission which are generally quite low (<1% in Collection 4)

•Data dependencies and error propagation through sequence of products must be understood because the higher-level snow and sea ice products are built from the swath product

• MOD11 and MCD43 use MOD10 products as input

•MODIS daily snow-cover 500-m (MOD10A1 & MYD10A1) and CMG 0.05-deg (MOD10C1 and MYD10C1) products are well suited for development of CDRs

•MODIS daily sea ice IST 1-km (MOD29P1D & MYD29P1D) and daily global (MOD29E1D & MYD29E1D) products are well suited for development of CDRs (Scambos et al., submitted)

•Daily and composited products have proven useful for developing snow-cover depletion curves for modeling (Dery et al., 2005) and operational (M. Budde/USGS) uses

•USGS uses MODIS snow products in a model to map SWE in Afghanistan in a Famine Early Warning System (M. Budde/USGS)

•Streamflow forecasts with two-week lead-time using the VIC hydrologic model were improved through inclusion of MODIS snow maps to update model, in 71% of reported forecasts overall (McGuire et al., 2005)

•Note the increase in number of MODIS-snow publications in 2005!Note the increase in number of MODIS-snow publications in 2005!

Page 33: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Backup slides

Page 34: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Input MODIS Level 1B bands 1, 2, 4, 6 (MOD02_HKM ), 31 & 32 ( MOD02_1km)

Input MODIS 1-km resolution geolocation, cloud mask MOD35 and land/water mask

MOD03

Calculate NDSI, NDVI, grouped-criteria tests, vegetation polygon

Apply surface temperature screen ( 283K)

Swath snow 500-m product MOD10_L2

(includes FSC)

Daily snow tile product 500-m

resolution MOD10A1

(includes daily snow albedo)

Daily snow CMG 0.05° resolution

MOD10C1

8-day composite snow tile product 500-m resolution

MOD10A2

8-day composite snow CMG 0.05° resolution

MOD10C2

MODIS data-product sequence

Algorithm Algorithm HeritageHeritage:

Kyle et al., 1978

Bunting and d’Entremont, 1982

Crane and Anderson, 1984

Tucker et al., 1985

Dozier, 1989

Romanov et al., 2000

Monthly snow CMG 0.05° resolution

MOD10CM

Page 35: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

False snow due to cloud shadows can be eliminated by application of a screen for low reflectance situations; the result of screening in right image shows that the erroneous snow is virtually eliminated,

with only four “snow” pixels remaining.

17 August 2004

Before screen After screen

MOD10_L2 MOD10_L2

Error of commission in the tile (left) is 0.074% of the land area and tile (right) is 0.003%

Page 36: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

Snow albedo swaths - North America

Daily snow albedo product (MOD10A1) Daily snow albedo product (MOD10A1) 500-m resolution500-m resolution

Nov. 22, 2003

Nov. 27, 2003

Albedo (%)Klein, 2003

Page 37: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

April 12, 2004

SnowStar snow map MOD10_L2 snow mapsnow 15.6 % snow 17.8 %

SnowSat map courtesy of Rune Solberg/Norwegian Computing Centre

Maps generally agree well when Norwegian land/water mask and both cloud masks are used in both maps

Hall et al., 2004

Page 38: MODIS Snow and Sea Ice Data Products at the EOSDIS NSIDC DAAC Dorothy K. Hall Cryospheric Sciences Branch, NASA/GSFC and George A. Riggs SSAI Kimberly

MOD10CM: 0.05 Monthly Climate-Modeling Grid (CMG) Snow Maps

February 2004

Percent Snow Cover