Here is some project data.  I started taking data from the base station at 16:18 EST, and stopped at 11:54 EST (basically, to show what happens when the sun sets).

Here is the supercapacitor stack voltage versus time.  After the sun starts to go down the voltage starts going down too (the GPS is still periodically activated).  Then, once the voltage dips below 3.4 V, then just the low power accel/magnetometer is active along with the ISM radio, so the voltage on the stack decreases more slowly.  It was cloudy this morning, so the charging of the capacitor was slower until the clouds moved off.

Here is the temperature as reported by the ATMEGA256RFR2.

Here is the magnetometer data (no pole flip, yet...).  Data looks somewhat correlated to the temperature for the X (black) and Y (blue) reading (temperature compensation is on for register 0x60), but not for Z (red).

Here is the accelerometer data:

Lastly, here is the GPS reported UTC time.