Atlas of Ocean Winds and Currents

Download or read book Atlas of Ocean Winds and Currents written by A. Phillips and published by Createspace Independent Publishing Platform. This book was released on 2011-12 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the latest ocean wind information collected by NASA satellites over ten years. It replaces the old pilot charts which were collected from sailing ship logs. These charts have never been published before. This is valuable information for sailors and seamen doing ocean passages. 12 monthly charts. From its orbit onboard the QuikSCAT satellite, the SeaWinds instrument samples 90 percent of the Earth's oceans every 24 hours. SeaWinds sends pulses of microwave radiation down to the wind-roughened surface and measures the backscatter of that radiation that returns to the satellite. From this data, wind speed and direction can be estimated. This knowledge has long been limited by poor in situ coverage by buoys and ships. Among the researchers' findings: - Earth's windiest ocean location is Cape Farewell, Greenland, where gale winds blow 16 percent of the time. - Half of the top 10 windiest spots occur where tall coastlines or high mountains meet the sea. - Strong winds are much more frequent on the warm side of cold-warm fronts formed where the Atlantic's warm Gulf Stream flows northward into cold ocean regions. This gives climate scientists important clues about how sharp differences in ocean surface temperatures affect the atmosphere, with warm ocean temperatures creating an unstable atmosphere that sucks strong winds down from aloft. - Typhoons and hurricanes have little impact on the frequency of overall high winds, since they are less frequent than other types of storms in Earth's mid-latitudes. "People know high winds are found in big storms," said Xie. "What is most surprising from our research is that narrow ocean currents have such a large effect on the occurrence of high winds. For example, in cold meanders (bends) of the Atlantic's Gulf Stream, the frequency of high winds drops by an order of magnitude. This knowledge can provide navigators with a 'safe harbor' for ships."