Tutorial

Hello and welcome to this brief tutorial of Snow Cloud Metrics. We provide a text-based tutorial accompanied by short videos. The full video tutorial is also available.

For more detailed explanations of Snow Cloud Metrics and related research look at the Research & Papers page.

Introduction (click to expand text instructions)

There are two required parameters for Snow Cloud Metrics. The first is water year (WY). A WY in the Northern Hemisphere begins on October 1 and ends on September 30. For example, WY 2008 starts on October 1 2007 and ends on September 30 2008. All of the data in Snow Cloud Metrics are currently organized by WY in the Northern Hemisphere. We look to incorporate the Southern Hemisphere's WY in the near future.

The second required parameter is Selecting a Region of Interest. As you can see there are several different options available.

For this demonstration we will use the US State of Montana.

Once you define the water year and region of interest, the Submit button will appear.

As the map updates calculations are made on the Google Earth Engine platform, and will display the Snow Cover Frequency and Snow Disappearance Date in the map.

For visual analysis of the data, legends for both layers can be toggled on and off. Similarly the locations of SNOTEL can be toggled on and off.

User-defined parameters

There are two required parameters for Snow Cloud Metrics. The first is water year (WY). A WY in the Northern Hemisphere begins on October 1 and ends on September 30. For example, WY 2008 starts on October 1 2007 and ends on September 30 2008. All of the data in Snow Cloud Metrics are currently organized by WY in the Northern Hemisphere. We look to incorporate the Southern Hemisphere's WY in the near future.

The second required parameter is Selecting a Region of Interest. As you can see there are several different options available.

For this demonstration we will use the US State of Montana.

Once you define the water year and region of interest, the Submit button will appear.

As the map updates calculations are made on the Google Earth Engine platform, and will display the Snow Cover Frequency and Snow Disappearance Date in the map.

For visual analysis of the data, legends for both layers can be toggled on and off. Similarly the locations of SNOTEL can be toggled on and off.

Elevation filter

You can also spatially filter the results by elevation. For example, if you were only interested in elevations between 2000 and 2500 meters, you can enter these parameters and run the analysis again.

Point-specific & time series data

For location specific data you can simply click on an individual point on the map, and get the point specific data for each location. Similarly, you can add additional locations by clicking additional points in the map.

Snow Cloud Metrics also provides the ability to generate time series analysis of the points. You need to click on the button "Add point(s) to time series charts".

If you want to add an additional points, you can do that too by simply clicking in the map..

These plots and the time series data are exportable as well. Simply click on the icon in the upper right corner of the plot and it will open in a new window.

Global extent and user defined areas

Remember that Snow Cloud Metrics provides global snow data. If you are interested in a specific area of interest, you can define your own polygon. For example if you wanted to look at SCF and SDD in the Pyrenees, simply reset the map and navigate your way to the border between Spain and France.

To define your own polygon use the polygon tool within the map interface, and then click points in the map to draw out your region of interest. Double click when you are ready to close the polygon. Then click submit in the interface on the left.

Downloading and getting code

This version of Snow Cloud Metrics does not provide the downloading of the spatial data directly from the app. If you need the spatial data, you can access our code provided on our GitHub page and run these same analyses in Google Earth Engine.

We provide more detailed information on the science and how these metrics were calculated, and some case studies of how they can be applied. If you have used these data please let us know what you did.

Thanks for your interest!