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Fig. 7-15, p.182
Single cell model: simple but not good enough, e.g., our surface winds do not flow N-S.
We really do need to include Earth’s rotation and land masses in a more complex model
sun
Unequal heating of surface by the Sun (the beginning of ALL weather).
Uneven energy input is redistributed by atmosphere and oceans
convective cell
convective cell
Fig. 7-16, p.183
Three cell model: much better, but not perfect.
Here we “allow” rotation, but still have ocean-covered planet.
Land masses obscure this predicted three-cell pattern.
Must be an odd number of cells: what goes up at beginning of first cell must be “balanced” by what comes down at end of last cell.
Could be 1, 3, 5, etc. Three on Earth dictated by rotation speed. On Venus, where rotation is very slow, only one cell develops.
Predicted surface winds after PGF and CF included
Fig. 7-15b, p.182
Minot, N. Dakota (48 N)
Tucson, Arizona (32 N)
easterlies
westerlies
Fig. 7-17a, p.184
Subtropical high
Subtropical high
Subpolar low
(shows up as a trough, as predicted)
Subpolar low
Equatorial low
Fig. 7-17b, p.185
Pacific H has moved N. and W. allowing sinking, warming air to subside along Pacific coast
Bermuda H. has moved S. and W. driving air to thermal low over AZ and setting up conditions for monsoons
For more about the monsoon see http://www.wrh.noaa.gov/twc/monsoon/monsoon.php
Fig. 7-18, p.186
Fig. 7-19, p.187
Elevated inversion due to sinking air from Ferrel cell, which warms as it compresses on the way down to the surface (see Fig. 12.12).
Fig. 7-20, p.187
During summer, the eastern edge of the Pacific High is well situated to force sinking warming air down over Los Angeles causing a strong elevated inversion that prevents convection and clouds/rain (see Fig. 7.17b).
Fig. 7-21, p.187
Polar low
Fig. 7-22, p.188
Fig. 7-23, p.189
Fig. 7-24, p.190
For us, the following are the most important ocean currents:1) Gulf Stream2) North Atlantic Drift3) Newfoundland Current9) South Equatorial Current16) California Current17) Peru (Humbolt) Current
Table 7-2, p.190
Fig. 7-25, p.191
If the CA current brings cold water down from Alaska then why is the coldest water halfway down the coast and not further north?
Answer – upwelling.
Cold CA current
Fig. 7-26, p.191
Upwelling of very cold water from the bottom of the Pacific is evident off San Francisco
Coriolis “force” causes ocean current to deflect to the right, i.e., offshore
Fig. 7-27, p.193
ENSO = El Nino/Southern Oscillation (in atmospheric pressure and wind direction)
Fig. 7-28, p.194
Current sea surface temperature animation:http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_update/sstanim.html
97/98 El Nino animation:http://www.cdc.noaa.gov/map/clim/sst_olr/old_sst/sst_9798_anim.shtml
“Temperature anomaly” scale
Fig. 7-29, p.195
Very weak ENSO this winter: warmer/wetter conditions to SE AZ
Table 7-1, p.168