Outline the processes involved in coastal upwelling and downwelling. What will be an ideal response?
Wind blowing parallel to shore or offshore can cause coastal upwelling. The friction of wind
blowing along the ocean surface causes the water to begin moving, the Coriolis effect
deflects it to the right (in the Northern Hemisphere), and the resultant Ekman transport moves
it offshore. Coastal upwelling occurs when this surface water is replaced by water rising
along the shore. Because the new surface water is often rich in nutrients, prolonged wind can
result in increased biological productivity. The opposite processes occur during downwelling.
Wind blowing from the south along a Northern Hemi- sphere west coast for a prolonged
period can result in downwelling. Water driven toward a coastline will be forced downward,
returning seaward along the continental shelf. Ekman transport moves water shoreward to
replace the water. This downwelling helps supply the deeper ocean with dissolved gases and
nutrients, and it assists in the distribution of living organisms. Areas of downwelling are
often low in nutrients and therefore relatively low in biological productivity.
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A risk is
A. something that is always to be avoided. B. involves a biological or chemical hazard. C. a lifestyle choice. D. the probability of suffering harm from a hazard E. is inherently transmissible.
What type of feature is found between Jenner Beach and Goat Rock? Describe how it appears and how it differs from other similar features.
What will be an ideal response?
?Match the term with the most appropriate description.
A. ?the earth's innermost zone, consisting of solid and molten portions B. ?outermost and thinnest zone of solid material C. ?rigid, outermost part of the mantle D. ?a thick zone made mostly of solid rock that can be soft and pliable at very high temperatures E. ?layer of hot, flowing, partly melted mantle rock
If a stream-cut canyon is deep and narrow, which of the following is most likely to be true?
A. Rocks in the canyon walls are relatively hard and so easy to erode. B. The stream contains mostly small clasts, such as silt. C. The stream is probably close to its base level. D. Downcutting is occurring faster than widening.