NDBC Science Education Pages
Are wind speeds the same over land as they are over the ocean?
The answer is NO! They are not the same. The accompanying graph will help to show this.
This graph shows wind speeds measured at two locations within 16 miles of each other. Station 46060 is a buoy which is located on the water in the Gulf of Alaska. Station BLIA2 is a land-based station situated on the coast of the Gulf of Alaska. As you can see, the wind speeds from Station 46060 are greater in magnitude than the speeds from Station BLIA2.
The reason this is so is that the characteristics of the land surface such as trees, plants, buildings, sand, mud, and rocks slow the wind because of the friction that exists between the wind and the land surface.
You can test the effects of friction by doing three simple exercises:
So, from our experiment, we can conclude that carpet and grass provides more friction than a table or a desk. We can also conclude that a wet table or desk has less friction than a dry table or desk.