James Madison University

Wind Characteristics

Wind temperature characteristics

Temperatures vary according to the amount of sun the earth receives. Uneven heating of the Earth's atmosphere and surface occur. The balance between warm and cool air is constantly changing, creating wind. Warm air rises from the surface and cool air sinks from higher in the atmosphere. This continuous cycle creates wind.

Characteristics of Wind

The wind doesn’t blow all the time and doesn’t blow everywhere all at once, making it an intermittent resource. For instance, the solar resource is relatively spatially consistent throughout Virginia; it is also very predicable- the sun will shine during the day and not at night. However, the wind resource varies daily and seasonally and does not blow consistently due to topography such as mountains and valleys. However, wind is predictable.

Winds are typically stronger and blow more frequently in the winter months. Winds are stronger in the fall and early spring as can be seen in the figure below, when the biggest changes in air temperature occur. You can also see in the figure below that wind speed increases with height above the ground, as the anemometers at higher heights show faster wind speeds. This is usually due to a lack of obstructions allowing air to flow uninterrupted at higher heights.

Wind speed characteristics monthly

Onshore winds are also strongest right before dawn on a daily cycle because this time is when the biggest transition occurs from cool to warm air. In a coastal location like the one in the figure below, the highest wind speeds are during midday, when sea breezes are strongest. This is known as the diurnal cycle.

Wind speed characteristics diurnal