People who advanced knowledge of the seas.
Pytheas: 4th cetury BC. Pytheas was a Greek mathematician and explorer who sailed in a trireme (a galley with 3 banks of oars) from what is now Marseiles, France out into the north Atlantic. As longitude was nigh impossible for these early sailors it is not entirely clear exactly where he went, but as he accurately described sea ice, it seems that he got as far as the Arctic circle his writings also indicate that he sailed around Great Brittain, He also brought back amber, so he may have entered the Baltic.
Ferdinand Magellan: A portugese soldier who defected to spain....after a lawsuit involving horses(!!?). As spices were very valuble in Europe then, he proposed sailing around the newly discovered Americas to the source of the spices in Asia. He left with 5 ships and sailed to south America, where 2ships returned. After a passage through the modestly named straits of Magellan, he sailed across the Pacific ocean, ending up in what is now the Phillipines, where he met the bane of explorers...."friendly natives" who killed him horribly. Of the original 5 ships and 260 men only 1 ship and 34 crew survived. His expeditions track line is on page 17 of the text.
note that as Magellan died, he did NOT become the first to circumnavigate the earth his expedition did.
James Cook: Used Harrisons #4 clock to accurately determine longitude. He attempted a transit of the Northwest Pasage (unsucsessfully) but used his ability to determine longitude to create maps of an accuracy never before seen. Small islands were accuately charted for the first time, amongst them Hawaii, where, upon meeting Friendly Natives, Cook was killed horribly.
Charles Wilkes: One of the first to produce charts on engraved plates for mass printing. This vain arrogant and generally disagreeable officer led a very important but underated expedition, the cryptically named, US Exploring Expedition. On the Frigate USS Vincinnes he charted the nothwest coast of North America as well as Wilkes Land in Antarctica, He gave charts to Ross who took credit for some of wilkes discoveries, namely Antarctica. (Antarctica had first bgeen sighted by the US Palmer expedition in 1825, but it was not realised it was a continent).
James Clarke Ross: Discovered north magnetic pole, and made it as far as 82 degrees north and 78 degrees south. Ross is given credit for discovering antarctica but his real contribution was the discovery that thre were identical marine organisms in the arctic and ant arctic. He hypothesised that there must be a bottom current connecting the 2 areas. He was correct.
Fritdjof Nansen: Built the FRAM, an early icebreaker for the specific purpose of getting stuck in the ice and drifting. He pionered study of arctic circulation patterns and developed several oceanographic implements including the nansen bottle for taking water/ temperature samples. ALL OF HIS CREW SURVIVED!!
William Anderson: Commanded USS Nautilus,the first nuclear submarine, on an expedition to the north pole in 1958.On the third try, after fixing gyros, and instaling TV cameras they made it. Ice up to 135 feet thick was discovered. The Nautilus also transited the northwest passage by simply going under the ice.
************************
Origin of oceans.
see figure page 40 for origin of planets.
H2O has high specific heat because it is a polar molecule.
Greatest annual rainfall 1,041.78 inches Cherapunji India 1860-61
(In USA) 57 inches in Puuku-Kui Maui 1950
Largest Hailstone 1.67 pounds Coffeyville Kansas
Look at diagram on page 2 of text.
At 50 degrees south water can go all the way around the planet.
There are 3 main parts of the earth
lithosphere,
hydrosphere,
atmosphere
There has been considerable variation in sea level , for example:
18000 years ago sea level was 180 meters lower
130,000 years ago it was 6 meters higher.
Contenental crust is less dense but some of the oceans cover parts of it (the contenental shelf) Continental crust is composed of granite type rocks while oceanic crust is composed of basalts.
look at the diagram on page 46 for perspective on time scales.
look at diagram on page 44 for explanation of gas composition of early atmosphere...
Earliest life was likely chemosynthetic.
READ CHAPTER2
