The boat has an interesting variety of low-tech and high-tech sensors. Perhaps the simplest is the 'ice drifter'. It is just a suitcase placed on an ice floe full of batteries that power two things: 1) A GPS receiver, and 2) A satellite phone transmitter that transmits the location. When the batteries die or the ice melts, that sensor is done. (The first versions floated after the ice melted, and ended having quite a phone bill. Current version have some holes drilled in the suitcase (Yes, liquid ocean current drifting data is useful too, but I guess the project wasn't funded for that)).

 If you want to follow along with a high-tech sensor you can. Search for "ARGO Drifter". These little yellow drifters get put directly into the water, not on ice. They go down to a pre-programmed depth, maintain neutral buoyancy, float along, and every so often rise up to the surface and report the data they collected. Repeat for a few years. It is smart enough to detect when it is attempting to surface while under ice and waits until open water. You can watch them in realtime on the ARGO website. Let me know if you see any that we deployed.