We use hand-held anemometers to accurately measure the wind's speed. As the wind blows through and spins an anemometer's fan, the electronic instrument records the wind's highest and average speeds.
When at sea, it's possible to measure wind speed with reasonable accuracy even without the use of precise instruments. The Beaufort scale estimates wind speed by categorizing observable water conditions into 12 "sea states," ranging from 0 (dead calm) to 12 (hurricane).
When we study wind speed in depth for research projects, we often simultaneously compare wind speeds on deck and at the mast tops. Our findings during these experiments indicate that the wind is consistently stronger at higher elevations.
This would have come as no surprise to the shipwrights who constructed the original d'Halve Maen in 1608; after all, top sails are desined specifically to harness those higher, more powerful gusts.
