Note how sharply the stream's north wall is confined, and how the banks of Cape Hatteras deflect the stream eastward. Chart T1, shows a portion of the Gulf Stream in the northwest quadrant of the Atlantic Ocean. Today, however, instead of a thermometer being placed in the ocean to record temperature (as Franklin used), satellite infrared imagery and altimetry, combined with color enhancement. The procedure for defining these currents is no different than that used by Benjamin Franklin-differences in water temperature are measured. Each meander and eddy of the Gulf Stream is mapped almost as quickly as it develops. Today, Government agencies continuously monitor all the major cold water and warm water currents of the ocean with great accuracy. This body of knowledge grew slowly dependent on many voyages over the years before general patterns were discerned. Throughout the centuries, mariners have used their knowledge of the ocean currents to plan speedy voyages. The URLs were correct as of 27 September 2000. The URLs provided with each image point to the websites of the organizations and to their current images and not to the actual images reproduced.
#Grads plot hurricane track eah point archive#
Note that those organizations d not necessarily archive their daily or monthly maps of sea surface temperature, etc. Note: all of the images in this section of the exhibition are reproduced here by the permission of their generating organizations. Commercial shippers, commercial fishermen, research scientists, and recreational sailors all benefit from this new era in marine cartography. Data that at one time was too transitory in nature to be disseminated in a timely fashion is instantly accessible electronically. Much of this material is then organized and transformed by computer.
Now, satellites commonly circle over our globe, taking photographs and measuring many of the ocean's characteristics with special sensors. Then, more time was needed to collate the material, engrave new plates, print, and finally dispense charts to the waiting public. Up until the mid-1970s there was a delay of weeks, if not months, for the data acquired by mariners to reach cartographers. It is still an ongoing process indeed, there is an explosion in the amount and kind of new information now available. Contrary to what one might expect after centuries of exploration, the charting of Neptune's Realm is not complete.
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