SnowEx Mission and Core Data Sets

by: Megan Mason (ATA Aerospace and Boise State), Carrie Vuyovich (NASA Goddard), HP Marshall (Boise State)

(12 minutes)


Tutorial objectives:

  • Provide background for the NASA SnowEx Mission

  • Distinguish the different components of the core data

  • Describe the sampling design and naming convention

  • Provide examples to extract and prep data of interest using 1). NSIDC downloads and 2).snowexsql database

SnowEx Background

What is the Mission of SnowEx?

SnowEx is a multi-year program funded by the NASA Terrestrial Hydrology Program to address the most important gaps in snow remote sensing knowledge. It focuses on airborne campaigns and field work, and on comparing the various sensing technologies, from the mature to the more experimental, in globally-representative types of snow. The goal is to address the most important gaps in our snow remote sensing knowledge, and thus lay the groundwork for a future snow satellite mission.


Where has SnowEx been?

Campaign efforts are focused on various snow climates in the Western United States. SnowEx partnerships and expertise are spread across the US and international. ../../_images/WhereHasSnowExBeen.png

What are the core data sets and what makes them different from other data?

The core data sets are standardized manual ground observations collected by SnowEx participants. These observations provide a legacy data set for the purposes of calibration and validation efforts for the remote sensing instruments.


What is a snow pit? ⇨ ‘Layer data’ & ‘Site data’ in the snowexsql database

A snow pit is a vertical profile of snow from the snow surface to the ground.
This is where we collect a suite of ground observations that aid instrument and model development.

What are depth transects? or simply depths‘Point data’ in the snowexsql database

These are point meausurements that tell you how deep the snow is at georeferenced locations.
There are several instruments available to capture snow depth, some of which are an avalanche probe, MagnaProbe, or Mesa2.

What is an interval board? ⇨ data not processed yet for database

An interval board is a 2x2” board with a vertical pole attached at the center.
The board surface is our reference to track the amount of new snow that falls between field visits.
The board remains fixed for the season, and gets cleared each visit.

Table. Summary of Core Data Sets with DOI links for applicable data sets

Core Data Sets Parameters Available Instruments NSIDC DOI
Snow Pits Depth, Density, Temp., LWC, Stratigraphy,
Grain Size, Wetness, Hand Hardness,
Qualitative Environment, SWE
Standard pit kit SNEX17_SnowPits_GMIOP
SNEX20_TS_SP (in prep.)
SNEX21_TS_SP (future pub.)
Depth Transects Snow Depth - various sampling designs MagnaProbe, Mesa2, Pit Ruler SNEX17_SD
SNEX20_TS_SD (future pub.)
SNEX21_TS_SD (future pub.)
Interval Boards New snow, SWE, density Ruler and spring scale SNEX20_TS_IB (future pub.)
SNEX21_TS_IB (future pub.)

Visit NSIDC’s SnowEx Overview page to see a full table of all available 2017 and 2020 products.

What data are associated with a snow pit?

Fieldnote photos from one pit visit. We call these Pit Sheets.

../../_images/SnowEx20_SnowPits_GMIOP_20200212_2C12_book1_v01.jpg ../../_images/stratCodes.png ../../_images/SnowEx20_SnowPits_GMIOP_20200212_2C12_book2_v01.jpg

What format are the data in?


Sample design and site naming convention


Nine-member snow and vegetation matrix

Vegetation classes

  • 1-3 = treeless (0% tree cover)

  • 4-6 = sparse (1-30% tree cover)

  • 7-9 = dense (31-100% tree cover)

Snow Depth classes

  • 1, 4, 7 = shallow (<90cm)

  • 2, 5, 8 = medium (90-122cm)

  • 3, 6, 9 = deep (>122cm)

Flight Lines

  • ‘C’ = Crossline

  • ‘N’ = North

  • ‘S’ = South



  • SnowEx is a participant driven and NASA funded project to lay the groundwork for a future snow satellite mission.

  • Pits, depths, interval board data sets are consistent between SnowEx sites and intended for calibration and validation efforts.

  • Published data (pits & depths, GMIOP ‘17 and ‘20) are available at NSIDC and the User Guides are very helpful! And, integrated into the snowexsql database!

Thank you to the SnowEx leadership team, logistics staff, data management personal, field participants, and you - the END USERS! ../../_images/field-mouse.JPG

By eScience Institute, University of Washington
© Copyright 2020.