Apparent wind that measures wind speed in knots and wind direction in degrees relative to the heading of the boat. Modern instrumentation can calculate the true wind velocity when the apparent wind and boat speed and direction are input. In sailboat racing, and especially in speed sailing, apparent wind is a vital factor, when determining the points of sail a sailboat can effectively travel in. A vessel traveling at increasing speed relative to the "prevailing wind" will encounter the wind driving the sail at a decreasing angle and increasing velocity. Eventually, the increased drag and diminished degree of efficiency of a sail
Wind power in Thailand highest wind energy potential in Thailand. The stations were installed to measure wind speeds at 80, 90, and 100 m heights. Also, from 2007 to 2009 wind speed and direction were measured and recorded from several stations in the northern Thailand. In 2011, research to improve the wind map was conducted by the Department of Physics of Silpakorn University. The research produced mesoscale wind maps with resolution of 3x3 km cells using atmospheric model and computer simulation software, and also experimented with the making of microscale wind maps, which could be the next step in the study of Thai wind