A sniper team typically consists of a sniper and a spotter as described in military doctrines of the United States, Canada and United Kingdom. Both members can perform either role and often rotate between the two. The sniper fires the shot while the spotter assists in observation of targets, atmospheric conditions and handles security of their immediate location and communication with other parties, including directing artillery fire and close air support. The spotter detects, observes, and assigns targets and watches for the results of the shot. Using his spotting scope, he will also read the wind by using physical indicators and the mirage caused by the heat on the ground.