|MadSci Network: Earth Sciences|
The atmosphere is in a constant state of change, whether it be over land or water. As weather systems strengthen and weaken, pressure fields change, and as a result, so do winds.
Over open ocean, pressure can be affected by things such as differences in sea surface temperatures, nearby storms, and by differential heating due to cloud cover.
Another phenomenon which often causes gusty winds over open water is cold air advection over the relatively warmer water. This often occurs behind cold fronts. As cooler air moves out over the warmer water, the atmosphere becomes unstable. The lower levels of the atmosphere 'turn over' allowing gustier winds to mix down to the sea surface.
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