nwaves A Unique Planet Life would not be possible without large amounts of water. Water has the ability to retain heat, moderate temperature, dissolve many chemicals, and suspend nutrients and wastes. All life, from a jellyfish to a dusty desert weed, depends on saline water within its cells to dissolve and transport chemicals..indicating that simple, self-replicating-living molecules arose somewhere in the early ocean. How long ago …probably at least 3.4-3.5 billion years ago as the oldest fossils yet found indicate. • The most striking and distinctive feature of our planet, when viewed from space, is the amount of water on its surface. Its called the water planet. And, while some is contained in clouds as water vapor and a few percent is present in lakes, rivers ice caps and in cavities of pores of rocks, most is contained within the oceans. The sea probably played a part in man's life and experience from the very earliest times, even his prehuman ancestors are likely to have included shellfish from the shore in their diet. • Water transportation was used at least since 50000 years ago to colonize Australia and maybe even longer but little trace remains because of the materials used for primitive boat building, reeds, wood, skins rapidly decompose. While the Greeks, Pacific Islanders and Vikings were responsible for some of the earlier spectacular maritime achievements, the Portuguese sea men were the first true pioneers of European oceanic exploration. Sent out by Prince Henry in 1420's they continued new discoveries, and charted these with considerable skill. In the 1460's they devised a system of nautical astronomy to improve navigation. The map shows the world known to Homer at about that time, and shows that knowledge of the seas was centered in the Aegean, and extended generally throughout the eastern Mediterranean. The Greeks of that time imagined the world to be a large disk with upturned edges, with the center of the disk in the Aegean, surrounded by a river. Page 1 nwaves Although the Phoenicians had traveled into the Atlantic centuries earlier, the Greeks were probably unfamiliar with the Atlantic Ocean, or any seas beyond the Mediterranean. Between the eighth and sixth centuries BC, Greeks of the historic period began voyaging more extensively beyond the Aegean, although not venturing out of the Mediterranean until the fourth century BC.. Renewed interest in natural history began to increase by the 16th century, and over the next few hundred years there were many studies carried out by what we would today call amateur naturalists. These were usually professional men in other fields, often physicians or explorers, but generally were individuals not specifically employed to carry out natural history studies. Notable among these are the explorations of Humboldt and of James Cook, who made extensive voyages and observations of the natural world. One of the early professional naturalists that made significant contributions to marine biology was Charles Darwin. Darwin, most famous for his later works on theories of evolution, was commissioned early in life as a naturalist on the The British ship HMS Challenger investigated the oceans worldwide between 1872-1876, finding a large number of new species. Sir Charles Wyville Thomson (Professor of Natural History at the University of Edinburgh, and director of the civilian scientific staff on the Challenger) published the findings of the Challenger expedition in a series known as the Challenger Reports. Until the middle of last century, marine biologists relied primarily on nets, grabs, and dredges to collect samples in almost every marine habitat except the intertidal zone, where collections could also be made by hand and Page 2 nwaves organisms could be directly observed. As an example of the ships and techniques, the U.S.S. Albatross of the United States Fish Commission carried out a number of expeditions from 1887 to 1925. Some of the equipment used on the Albatross are pictured below In 1934, zoologists William Beebe and Otis Barton were the first to observe relatively deep sea habitats directly aboard the "bathysphere", which remained tethered to a surface ship during the entire dive. They reached a depth of 923 meters (3,072 feet). The advent of modern Self Contained Underwater Breathing Apparatus (SCUBA), underwater photography, and manned submersibles have allowed us to see firsthand much of the marine environment that we previously could not observe. The development of a wide variety of electronic measuring devices and instruments, unmanned submersibles, and remote sensing by satellites and aircraft has also greatly increased our ability to measure and study parts of the marine environment that are difficult to observe in person. Even so, because of logistical problems associated with conducting research in much of the marine environment, our knowledge of conditions in most of the seas and oceans lags behind our knowledge of the terrestrial environment. • By the 1480's a pilot could calculate his latitude. Longititude could not be measured yet so "running down the latitude" was practiced...sailing to the latitude of landfall, for three to four hundred miles seaward and then sailing due east or west to the landfall. Columbus used his method on his return voyage from the New World. • It wasn't until 1760+ that John Harrison's fourth chronometer and the lunar distance method of calculating longitude provide answers to measure longititude at sea. Latitude and Longitude •1st and 4 th Chronometer by John Harrison Page 3 nwaves • Albatross • In August 1882, the United States Commission of Fish and Fisheries launched the first vessel built especially for marine research by any government—the steamer Albatross . Perhaps even more impressive than being the first government vessel equipped throughout with electric lights, Albatross has been credited with discovering more new marine species than any other research vessel. • The American Navy's' ship the Blake carried out research from 1877-80 in the Caribbean gulf of Mexico and coast of Florida and from there the science continued to flourish... Note names! • Pathfinder was the first survey ship to have a nautical chart printing press installed onboard. During World War II, the vessel churned out thousands of charts for fleet units. Captain Junius Jarman of the C&GS was instrumental in developing techniques for chart printing in a shipboard environment. Latitude and Longitude Longitude •On the globe, lines of constant longitude ("meridians") extend from pole to pole, like the segment boundaries on a peeled orange Latitude and Longitude •Every meridian must cross the equator. •Since the equator is a circle, we can divide it--like any circle--into 360 degrees, and the longitude of a point is then the marked value of that division where its meridian meets the equator. Latitude and Longitude Page 4 nwaves •Any location on Earth is described by two numbers --its latitude and its longitude. •If a pilot or a ship's captain wants to specify position on a map, these are the "coordinates" they would use. Latitude and Longitude •On a globe of the Earth, lines of latitude are circles of different size. •The longest is the equator, whose latitude is zero, while at the poles--at latitudes 90 ° north and 90 ° south (or -90 °) the circles shrink to a point. • Did you know that you can use the stars to tell directions at night? The North Star, or Polaris, is usually within 1-2 degrees east or west of true north. Polaris is at the top of the handle of the Little Dipper, a constellation that is easy to find in the Northern Hemisphere. • You can also use the North Star to determine latitude in the Northern Hemisphere. Use an astrolabe , used to determine the altitude of objects above the horizon, to find your latitude. You can make your own simple astrolabe using a protractor, plastic straw, 12-inch piece of string, and a metal weight (a small bolt or a washer works well). Tie one end of the string to the hole in the middle of your protractor. (If there is not a hole, drill one in the center of the flat-edged piece on the protractor.) Latitude and Longitude •1st and 4 th Chronometer by John Harrison Latitude and Longitude •What that value is depends of course on where we begin to count--on where zero longitude is. •For historical reasons, the meridian passing the old Royal Astronomical Observatory in Greenwich, England, is the one chosen as zero longitude. Page 5 nwaves Latitude and Longitude •Old Royal Astronomical Observatory in Greenwich, England, Latitude and Longitude •Located at the eastern edge of London, the British capital, the observatory is now a public museum and a brass band stretching across its yard marks the "prime meridian. “ • Tourists often get photographed as they straddle it--one foot in the eastern hemisphere of the Earth, the other in the western hemisphere. Latitude and Longitude • A lines of longitude is also called a meridian, derived from the Latin, from meri, a variation of "medius" which denotes "middle", and diem, meaning "day." •The word once meant "noon", and times of the day before noon were known as "ante meridian", while times after it were "post meridian." •Today's abbreviations a.m. and p.m. come from these terms, and the Sun at noon was said to be "passing meridian". Latitude and Longitude •All points on the same line of longitude experienced noon (and any other hour) at the same time and were therefore said to be on the same "meridian line", which became "meridian" for short. Latitude and Longitude •Time Zones • On the Mississippi river in the 1850s, the leadsmen also used old- Page 6 nwaves fashioned words for some of the numbers; for example instead of "two" they would say "twain".