Maximum sustained wind 50% of the geostrophic wind speed aloft; while over open water or ice, the reduction is between 10% and 30%. In most basins, maximum sustained winds are used to define their category. In the Atlantic and northeast Pacific oceans, the Saffir–Simpson scale is used. This scale can be used to determine possible storm surge and damage impact on land. In most basins, the category of the tropical cyclone (for example, tropical depression, tropical storm, hurricane/typhoon, super typhoon, depression, deep depression, intense tropical cyclone) is determined from the cyclone's maximum sustained wind. Only in Australia is this quantity not used to
Daniel Cornelius de Beaufort succeeded by Samuel Grove. De Beaufort married Esther Gougeon and they had a son Daniel Augustus Beaufort (1739–1821) who was a priest and distinguished cartographer. His son was Sir Francis Beaufort (1774-1857), Royal Navy officer and hydrographer and the inventor of the Beaufort Scale for indicating wind force. In 1746, de Beaufort accompanied the Earl of Harrington to Ireland as chaplain and in 1747 he received the benefice of Navan, Meath. In 1753 he was appointed to be Provost of Tuam and he later became rector of Clonenagh. Daniel Cornelius de Beaufort Daniel Cornelius de Beaufort (1700-1788) was rector of