uwhs oceanography: focus on washington waters lynne buechler
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UWHS Oceanography: Focus on Washington Waters
Lynne Buechler
Geography & Navigation
Geography: Shape of the EarthEarth not quite a
sphere creates a slight equatorial bulgePolar radius=6365
kmEquatorial
radius=6387 kmDifference is 22 km
or 13 mi!
http://www.see.leeds.ac.uk/structure/dynamicearth/internal/shape.htm
Geography: Shape of the EarthDistribution of continental
mass at mid latitude in the N. HemisphereSlight depression w/ an
elevation at the N. PoleAntarctica centered on the
S. Pole in the S. Hemisphere Inflated bottom half
This “pear” shape is actually a small effect and the Earth is fairly spherical
http://www.jpl.nasa.gov/news/news.cfm?release=2002-217
http://www.lead.org.au/bblp/Climate_Change/sld002.htm
Geography: Earth the Water PlanetOcean Planet
Oceans cover 140 million mi2 of earth’s surface71% of Earth’s
surface is covered by water
Total volume=1.35 billion km3
Physiographic MapsGraphic representations of major features
Navigation: Charts & MapsLab 1
Bathymetric ChartsAccurately reflect the topography of the ocean
floor by providing contour intervals of constant depth
Navigation: Charts & Maps
http://frank.mtsu.edu/~cdharris/honors/island-maps/Sigsbee-Plain.htm
oceanexplorer.noaa.gov
Navigational ChartsType of navigational chart with more
navigational aids: Signals> lighthouses, buoysLandmarksDangers> rocks, underwater cables, kelp beds, etc. Bottom Characteristics>
Rocks, sediment type, etc.
Navigation: Charts & Maps
http://www.dreamstime.com/stock-photo-nautical-navigation-chart-tools-image11097000
Datum= the “zero” level to which elevation and depth are referenced or sea level usually.
Sea level fluctuates with tidal movement Depth to seafloor= MLLW or “mean lower low
water” a tidal descriptive term is usedLand elevation=MHW or “mean high water” is
used
Navigation: Elevation & Depth
Geography: Latitude and Longitude
W E
Prim
e M
erid
ianEquator
N
S
Geography: Where are you?Where is the approximate
latitude of Covington? 122° 6' 49" W “Parallels” 1⁰ Lat.=111.32 km=60
Nautical MilesLongitude?
To the nearest second? 47⁰ 20’53”=47 degrees,
20hours, 53 minutes
Geography: What is the Puget Sound?Sound? Fjord? Estuary?Sound: complex of inland
waterwaysFjord: system of flooded
glacial valleysEstuary: semi-enclosed
coastal (salty water) body of water with one or more rivers or streams flowing into it
Mikelle Nuelle, professor of Oceanography UW
Richard Strickland, Professor of Oceanography UW
Sverdrup & Armbrust, Introduction to the World’s Ocean’s Ch 2
Sources