DEPARTMENT OF GEOSCIENCES NAME ________________________

San Francisco State University Spring 2005

Metr 201

Synoptic Metr Quiz #3

100 pts. (Picked Up at 9:35 AM)

A. Continuity (Dine's Compensation)

1. Examine the graphic below. It shows schematic air columns with arrows indicating the sense of the wind flow. (7 points each for 42 points)

Indicate the term or terms (there may be several) that apply to the locations shown from the choices given in the box on the next page.

Location 1 _ (a)

Location 2_ (b)

Location 3__ (c) (g)

Location 4___(b) (d)

Location 5___(a) (e)

Location 6___(c) (h) (f)

a. horizontal divergence

b. horizontal convergence

c. Level of Non-divergence

d. Falling surface pressures

e. Rising surface pressures

f. subsidence

g. vertical motion favorable for cloud development

h. vertical motion favorable for clear skies and fair weather

2. Write out the Principle of Dine's Compensation (8 points)

Upper tropospheric divergence tends to be balanced by lower tropospheric convergence with riding motion in between and vice versa.

B. Dine's Compensation on Weather Maps (50 points)

Examine the following charts, the first showing 300 mb convergence (divergence is negative), the second showing 500 mb vertical velocity (upward motion is positive) and, the third giving the 4 km infrared satellite image (not quite the same time as the other two charts, but close enough) for the West.

Write a short essay (a couple of paragraphs) describing how the above images (focus at locations A, B, C and D) are consistent with the Principle of Dine's Compensation.

At the four locations shown, we find 300 mb divergence, 500 mb upward vertical motion and deep cloud development suggested by the cold cloud tops on the infrared imagery.

According to the Principle, divergence in the upper troposphere, would be associated with upward motion in the mid troposphere and the vertical motion necessary to cause cloud development and precipitation. This is all consistent with the Principle of DineÕs Compensation.