More at http://cenm.ag/freezy Last March, scientists placed in the Arctic Ocean a buoy to measure chemicals in the atmosphere as part of a project called O-BUOY. The buoy contained chemical analysis instruments along with meteorological sensors, a satellite communications system, batteries and solar panels, and a camera. The buoy was transported out to the ocean by an icebreaker, then lowered into the ice by a helicopter.  
 
The O-BUOY instruments measure carbon dioxide, ozone, and bromine oxide in Arctic air. Carbon dioxide is a greenhouse gas and ozone and bromine oxide are key chemicals in Arctic atmospheric chemistry. Because it is difficult to collect data in the Arctic, not much is known about the concentrations of these compounds in the air, how the concentrations change over time, how the chemicals react, and the role of seawater or ice in the chemistry. The buoys stay in place until the ice melts, after which they float in the water. They continue to collect data until something happens to disable them, such as being toppled by a bump from a chunk of ice.