Seasonal Ice Mass Balance Buoy 3 (SIMB3) is a 4.87 meter long, 12 cm diameter spar-type buoy that measures how sea, lake, or pond ice change thickness through time. Once deployed, SIMB3 uses two ice-facing acoustic rangefinders to measure how the surrounding ice grows and melts. It also measures the vertical profile of temperature through the air, snow, ice, and water, as well as air temperature, barometric pressure, and GPS location. SIMB3 can measure ice up to 3 meters thick and snow up to 0.5 meters thick. It is equipped with a sealed battery and can operate autonomously for up to 1.5 years. Using an Iridium satellite modem, SIMB3 is capable of operating in anywhere in the world, transmitting data on user defined intervals (usually 1 or 4 hours). Immediately after transmission, data is uploaded to the Real-Time Data Portal for viewing and download.
Note: other diagnostic data such as battery voltage, transmission counter, and Iridium/GPS satellite count are also transmitted. For more details, see Getting Started with the SIMB3 datasheet.
|Maxbotix MB7374||Downward looking rangefinder||+/- 0.001 m||0.01 m|
|Airmar EchoRange +||Upward looking rangefinder||+/- 0.01 m||0.01 m|
|Bruncin DTC (3.85 m)||Digital temperature chain||+/- 0.5 deg C||0.125 deg C|
|DS18B20||Air temperature sensor||+/- 0.5 deg C||0.0625 deg C|
|BME280||Barometric pressure sensor||+/- 1 mBar||0.1 mBar|
|MTK3339 GPS||GPS module||3 m||~ 0.1 m|
* SIMB3 is buoyant, fully waterproof, and does not rely on the ice for mechanical support. Operation or deployment in open water is therefore possible, however results may vary.
** battery service life can vary significantly depending on the environment and equipped instruments.
*** transmission over the Iridium network requires a clear view of the sky.
**** while SIMB3 can be assembled without tools, an ice-auger is still required to drill the ice hole, a drill/screwdriver is required to remove the box top, and and a tape measure is recommended for recording initial ice and snow thickness and freeboard measurements.