MODIS Snow (MOD10)¶

MODIS/Terra and Aqua Snow Cover (MOD10, MYD10) Version 61 — NDSI-based snow cover, daily, 8-day and monthly, on 500 m tiles and the 0.05° Climate Modeling Grid, including cloud-gap-filled daily maps

Being replaced

At a glance¶

Note on period: Terra starts on 2000-02-24 (MOD10A1, A1F, C1), 2000-02-18 for the 8-day products (MOD10A2, C2) and 2000-03 for the monthly product (MOD10CM); all Aqua (MYD10) products start on 2002-07-04. On 2026-10-13 daily data from both satellites ran through 2026-10-11.

Overview¶

Global snow cover from Terra (MOD10) and Aqua (MYD10) MODIS, produced by the NASA MODIS snow team using the Normalized Difference Snow Index (NDSI) and a series of data screens. The daily 500 m tile product (MOD10A1) gives an NDSI snow cover value from 0 to 100 for each pixel; alongside it come a cloud-gap-filled daily product that fills cloudy pixels with the most recent clear view (MOD10A1F), 8-day maximum snow extent (MOD10A2), and daily, 8-day and monthly snow cover percentages on the 0.05° grid (MOD10C1, C2, CM). The record starts in 2000 and is widely used for snow climatology, melt timing and hydrological model evaluation; the VIIRS snow products continue it.

What changes with the successor¶

MODIS Snow Cover C6.1 (MOD10, MYD10) → VIIRS Snow Cover C2 (VNP10, VJ110) Planned¶

Transition: 2026

The VIIRS snow products were developed alongside the MODIS Collection 6 algorithm and use an almost identical approach (NDSI plus data screens), designed to continue the MODIS record. Resolution (500 m → 375 m), cloud mask, observing time and the set of products differ, so the records should not simply be joined.

Sources: Riggs, Hall, Román (2017) — overview of the MODIS and VIIRS snow ESDRs · Hall, Riggs, DiGirolamo (2024) — comparison of MODIS and VIIRS snow products (Great Basin) · Román et al. (2024) — continuity between MODIS C6.1 and VIIRS C2 land products · NASA Earthdata — Transition from MODIS to VIIRS (2025-05-02)

Compare the two side by side

MODIS Snow Cover Collection 6.1 (V61) → MODIS Snow Cover Collection 7 Planned¶

The MODIS snow team has published the Collection 7 User Guide (February 2025, Version 1.0) for the final reprocessing. The snow algorithm is the same as C6.1, with only improved Level 1B calibration; as of 2026-10-13 no C7 data were available at NSIDC or in CMR.

Sources: MODIS Snow Products Collection 7 User Guide (Riggs and Hall, 2025-02) · MODIS Land News (Collection 7 plans)

Available variables¶

Layer names from the MODIS Snow Products C6.1 User Guide (NSIDC). Files are HDF-EOS2 (HDF4). NDSI_Snow_Cover values 0–100 are NDSI × 100 (not fractional snow cover); 200 missing, 201 no decision, 211 night, 237 inland water, 239 ocean, 250 cloud, 254 detector saturated, 255 fill.

instantaneous mean accumulated maximum minimum static — instantaneous: value at the time stamp · mean/accumulated/maximum/minimum: over the indicated interval · static: does not change with time

Daily snow cover, 500 m (MOD10A1 / MYD10A1)¶

Cloud-gap-filled daily snow cover, 500 m (MOD10A1F / MYD10A1F)¶

8-day snow cover, 500 m (MOD10A2 / MYD10A2)¶

0.05° CMG snow cover percentage (MOD10C1 daily / MOD10C2 8-day / MOD10CM monthly)¶

The full variable list is in the official documentation.

How to get the data¶

• NSIDC DAAC data set page (MOD10A1 V61) — NSIDC Data Access Tool (date/area selection, Python script) / HTTPS / documentation
  • Terra products are MOD10, Aqua products MYD10. The list of all 22 MODIS V61 data sets is at https://nsidc.org/data/modis/data.
• NASA Earthdata Search and earthaccess (Earthdata Cloud) — Web search and download / earthaccess / AWS S3 (in us-west-2 only)
  • Since 19 August 2025 the legacy NSIDC archive (n5eil01u.ecs.nsidc.org) is closed and Earthdata Cloud is the primary archive. In CMR the short name is MOD10A1 with version 61 (no leading zero, unlike MCD43's "061").
• NASA AppEEARS — Point and area extraction with reprojection
• NASA Worldview — Web map visualization
  • Handy for checking daily snow and cloud patterns before downloading.

Example code¶

Downloads Terra cloud-gap-filled daily snow cover (MOD10A1F) over the Korean Peninsula for January 2024 with earthaccess and reads it. The files are HDF4, so pyhdf is used (pip install earthaccess pyhdf numpy).

import earthaccess
import numpy as np
from pyhdf.SD import SD, SDC

earthaccess.login()  # free NASA Earthdata account
results = earthaccess.search_data(
    short_name="MOD10A1F", version="61",
    temporal=("2024-01-15", "2024-01-15"),
    bounding_box=(124, 33, 132, 39),   # (west, south, east, north)
)
files = earthaccess.download(results, "mod10a1f")

for f in files:
    sd = SD(f, SDC.READ)
    ndsi = sd.select("CGF_NDSI_Snow_Cover")[:].astype("float32")
    cp = sd.select("Cloud_Persistence")[:]
    ndsi[ndsi > 100] = np.nan          # 200+ are codes for missing, night, water, cloud, etc.
    snow = ndsi > 0                     # example: treat NDSI snow cover 1-100 as snow (tune the threshold for your study)
    fresh = cp == 0                     # pixels clear today, i.e. observed today
    print(f, np.nanmean(snow), fresh.mean())

Practical tips¶

• NDSI_Snow_Cover values 0–100 are NDSI (× 100), not fractional snow cover. Since Collection 6 neither FSC nor a binary snow map is provided, so choose an NDSI threshold suited to your region and purpose and report it in your paper.
• Values of 200 and above (200 missing, 201 no decision, 211 night, 237 inland water, 239 ocean, 250 cloud, 254 saturated, 255 fill) must be removed first or averages will be badly wrong.
• About 75% of the Aqua MODIS band 6 (1.6 µm) detectors do not work. Collections 6 and 6.1 restore band 6 with Quantitative Image Restoration (QIR) and run the same algorithm as Terra, whereas Collection 5 Aqua data used band 7 and differ from Terra. Do not mix in old Aqua data.
• Cloud-gap-filled values (MOD10A1F) can be Cloud_Persistence days old. During fast-changing periods such as melt, exclude pixels with long cloud persistence.
• Known issues include cloud/snow confusion (cloud edges, thin snow flagged as cloud), Antarctica (frequent errors; not recommended), false lake ice in turbid lakes, and false snow on bright surfaces such as salt flats. Day-to-day geolocation wobble can blur lake and coastline edges.
• Orbit drift has changed Terra and Aqua crossing times, increasing low-sun observations. This can affect high-latitude winter and early-spring data and trends from the 2020s onward.
• Since 7 July 2023 Lights-Out-Operations have made non-recoverable gaps more frequent. Missing tiles are treated like cloud in the gap-filled product, so earlier values carry forward.
• The MODIS snow team has published a Collection 7 User Guide (February 2025). C7 keeps the algorithm but uses HDF-EOS5 and drops the 8-day (A2, C2) and monthly (CM) products and the snow albedo layer. On 2026-10-13 NSIDC still offered only V61.

Notices and change history¶

References for your paper¶

Dataset citation¶

MOD10A1 V61 (Terra daily, 500 m) — DOI 10.5067/MODIS/MOD10A1.061

@misc{mod10a1_v61,
  author    = {Hall, Dorothy K. and Riggs, George A.},
  title     = {{MODIS/Terra Snow Cover Daily L3 Global 500m SIN Grid, Version 61}},
  year      = {2021},
  publisher = {NASA National Snow and Ice Data Center Distributed Active Archive Center},
  address   = {Boulder, Colorado USA},
  doi       = {10.5067/MODIS/MOD10A1.061}
}

MYD10A1 V61 (Aqua daily, 500 m) — DOI 10.5067/MODIS/MYD10A1.061

@misc{myd10a1_v61,
  author    = {Hall, Dorothy K. and Riggs, George A.},
  title     = {{MODIS/Aqua Snow Cover Daily L3 Global 500m SIN Grid, Version 61}},
  year      = {2021},
  publisher = {NASA National Snow and Ice Data Center Distributed Active Archive Center},
  address   = {Boulder, Colorado USA},
  doi       = {10.5067/MODIS/MYD10A1.061}
}

MOD10A1F V61 (Terra cloud-gap-filled daily, 500 m) — DOI 10.5067/MODIS/MOD10A1F.061

@misc{mod10a1f_v61,
  author    = {Hall, Dorothy K. and Riggs, George A.},
  title     = {{MODIS/Terra CGF Snow Cover Daily L3 Global 500m SIN Grid, Version 61}},
  year      = {2020},
  publisher = {NASA National Snow and Ice Data Center Distributed Active Archive Center},
  address   = {Boulder, Colorado USA},
  doi       = {10.5067/MODIS/MOD10A1F.061}
}

MOD10CM V61 (Terra monthly, 0.05°) — DOI 10.5067/MODIS/MOD10CM.061

@misc{mod10cm_v61,
  author    = {Hall, Dorothy K. and Riggs, George A.},
  title     = {{MODIS/Terra Snow Cover Monthly L3 Global 0.05Deg CMG, Version 61}},
  year      = {2021},
  publisher = {NASA National Snow and Ice Data Center Distributed Active Archive Center},
  address   = {Boulder, Colorado USA},
  doi       = {10.5067/MODIS/MOD10CM.061}
}

Reference papers¶

Overview of the MODIS and VIIRS snow records — DOI 10.5194/essd-9-765-2017

@article{riggs2017snow,
  author  = {Riggs, George A. and Hall, Dorothy K. and Rom{\'a}n, Miguel O.},
  title   = {Overview of {NASA}'s {MODIS} and {Visible Infrared Imaging Radiometer Suite} ({VIIRS}) snow-cover {Earth System Data Records}},
  journal = {Earth System Science Data},
  volume  = {9},
  number  = {2},
  pages   = {765--777},
  year    = {2017},
  doi     = {10.5194/essd-9-765-2017}
}

Evaluation of MODIS and VIIRS cloud-gap-filled snow products — DOI 10.5194/hess-23-5227-2019

@article{hall2019cgf,
  author  = {Hall, Dorothy K. and Riggs, George A. and DiGirolamo, Nicolo E. and Rom{\'a}n, Miguel O.},
  title   = {Evaluation of {MODIS} and {VIIRS} cloud-gap-filled snow-cover products for production of an {Earth} science data record},
  journal = {Hydrology and Earth System Sciences},
  volume  = {23},
  pages   = {5227--5241},
  year    = {2019},
  doi     = {10.5194/hess-23-5227-2019}
}

Acknowledgements¶

NSIDC asks users to use the citation on each data set page (authors, year, title, version, DOI, access date and a description of any subset used). Cite the DOI of each satellite (MOD/MYD) and product (A1, A1F, A2, C1, C2, CM) you used. DOIs follow the pattern 10.5067/MODIS/.061 (e.g. MYD10A1F 10.5067/MODIS/MYD10A1F.061, MOD10C1 10.5067/MODIS/MOD10C1.061).

Information on the datasets used in this study was compiled with the help of the Korean Climate Data Navigator (KCDN) (Sim, 2026; https://doi.org/10.5281/zenodo.23300923).

Links¶

• MODIS Snow Products Collection 6.1 User Guide (PDF)
• MODIS Snow Products Collection 7 User Guide (PDF, 2025-02)
• NSIDC MODIS data set list (22 V61 data sets)
• MODIS Snow & Sea Ice Global Mapping Project (NASA GSFC)
• NSIDC Earthdata Cloud data access guide