This is part 4 of a 5 part series. Be sure to read the earlier parts first if you haven’t already.
- Getting the images on your computer
- Visualizing the data
- Examples: Lake Winnipesaukee; Lake Sunapee
- Getting the images while on the ice (this article)
- Additional information
4. Getting the images while on the ice
Okay, you’ve done your research, you’re headed out to skate, but how do you use the satellite images while out on the ice?
The most straightforward way is just to keep using the EO Browser website. It works great on mobile browsers.
But though that’s great for viewing the satellite data visualizations, you’ll have to jump back and forth between that and whatever other maps you’re using, and or whichever app you’re using to track your skate.
If you use Gaia GPS, there are two map layers you can use: “Fresh Sat – Recent” and “Fresh Sat – Cloud Free”. Here’s roughly the same view using the Fresh Sat – Recent layer, showing the gaps between ice plates clearly.
These use the visible light version of the HLS (Harmonized Landsat Sentinel) data, which has slightly lower resolution but updates more often. The “Recent” layer shows the most recent pass, regardless of cloud coverage; the “Cloud Free” layer shows the most recent pass that had less than 20% cloud cover. The map tiles have datestamps on them.
If you use Caltopo, you can make use of the “Sentinel Weekly” layers, and you can choose from several different visualizations. They call it “weekly” even though it’s 5-daily for simplicity.
You can also choose specific passes from the menu.
You can also download images from the EO Browser, for saving to your phone or for printing. If you’re not logged in (remember, accounts are free for non-commercial use), you can only download a basic image, which looks like this.
To get that, click the little image icon on the right side of the screen, then click the green “Download” button. You’ll probably also want to check the “Show legend” option.
If you’re logged in, you can download higher resolution images more suitable for printing.
I’m sure there are other good options as well, these are just the ones I know about and use!
That’s the whole tutorial, but continue on to part 5 for some additional notes.
— Christopher Boone, some rights reserved (CC BY-NC-SA 4.0)