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1 .Listen to part of a lecture in an earth science class.
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2 .Okay, before we finish class, I\'d like to briefly talk about something else.
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3 .Has anyone ever heard of something called flotsam science?
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4 .No. Well, I\'m not surprised.
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5 .It\'s a research method, but one of the more unusual ones out there.
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6 .Now, flotsam, of course, refers to cargo or wreckage from ships that\'s found floating at sea or washed up on shore.
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7 .Flotsam science began quite accidentally, some years ago
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8 .a shipment of plastic bath toys shaped like frogs, ducks and turtles
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9 .fell off a cargo ship into the Pacific Ocean in stormy weather.
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10 .No one thought too much of this.
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11 .It happens all the time.
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12 .But then these toys started to wash up onto beaches 1000s of miles away.
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13 .Scientists who track ocean currents were static.
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14 .Since they knew when and where that spill had occurred
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15 .they realized they could trace the roots these toys had taken as they floated through the Pacific.
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16 .So flotsam science is generally speaking
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17 .the science of floating junk
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18 .but this is a legitimate, if perhaps unconventional scientific discipline.
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19 .In fact, thanks to flotsam science and these traveling bath toys and other harmless stuff that drops off ships
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20 .like athletic shoes, sports equipment, you name it
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21 .scientists now know a lot more than they used to about currents in the Northern Pacific.
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22 .That information, in turn, has allowed scientists to identify long term changes in water temperatures
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23 .and salinity of the amount of salt in the water in these currents
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24 .before flotsam science, scientists had been trying to determine this information years by using expensive scientific devices that they would set adrift in the ocean.
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25 .But there are problems with these devices.
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26 .For one thing, they need to travel at great depths, as much as two kilometers down
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27 .because if they ride on the surface of the ocean, their sensors can become obstructed by algae, barnacles and other organisms
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28 .that thrive in the sunlit upper portion of the ocean.
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29 .But if they travel way below the surface to avoid these obstructions
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30 .well, they don\'t tell you much about the surface movement of the water
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31 .which is what we want to know.
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32 .Another problem is that their batteries don\'t last long enough to record sufficient data
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33 .but bath toys and athletic shoes and this sort of thing
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34 .they travel on the surface, and they don\'t need batteries
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35 .and a lot of merchandise that falls off ships, like athletic shoes
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36 .have manufacturing codes on them that scientists use in tracing the origin of these objects and keeping track of their movements.
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37 .And now scientists are using flotsam science for more than studying ocean currents.
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38 .For example, some scientists are trying to use lots of science
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39 .to study glacial melt water in the warmer summer months.
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40 .From the top layer of a glacier melts, forming pools of melt water.
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41 .So far, it\'s been a challenge to determine just how much is a glacier loses each summer
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42 .or where the meltwater winds up
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43 .because it travels through Moulins.
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44 .A moulin is a giant crack in the glacier that melt water drains through
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45 .and once melt water enters a moulin
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46 .it\'s extremely difficult to track.
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47 .One scientist set out to determine where melt water from a glacier in Greenland ends up
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48 .into which neighboring body of water.
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49 .So what this scientist did is he set a special scientific instrument
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50 .equipped with a tracking device down a moulin in Greenland\'s largest glacier.
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51 .Unfortunately, his rather expensive device disappeared.
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52 .Okay, so what else could be used?
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53 .Now you have to realize that conditions inside these moulins are intense.
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54 .It\'s freezing cold, plus there\'s the high pressure from the weight of all that ice above.
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55 .So what was needed was something really durable.
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56 .He finally decided to use yellow ducks
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57 .a children\'s bath toy
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58 .their advantage being that they\'re both cheap
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59 .and can withstand high pressures and low temperatures.
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60 .Well after printing his email address and an offer of a reward in three different languages on the ducks
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61 .he dropped 90 of them down the Moulin he was researching.
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62 .Now he hasn\'t actually had any of these ducks returned yet
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63 .but he remains hopeful that someone will find a duck and return it to him.
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