Weather and Climate 100 Help

View the files that are attached and please help complete!!!

AOS 100 Homework #4 Name:
Due Date: November 11, 2013

Student ID:

1. Suppose the surface pressure measured in Madison (at an elevation of 260 meters) is 984 mb.

a. What would the reported sea level pressure at Madison be, assuming air density of 1
kg/m2 and that the acceleration due to gravity is about 10 m/s2?

b. Would the reported sea level pressure be higher, lower, or the same on a cold winter day

(think about how density would be affected)? Briefly explain why.

2. Explain why the following statements are, or are not, true:

a. The only horizontal force that can increase the wind speed is the pressure gradient force.

b. Winds always circle counter-clockwise around a low pressure system.

c. In the northern hemisphere, the Coriolis force causes surface winds to veer to the left,

relative to the geostrophic wind.

d. The Northern and Southern hemisphere jet streams both tend to be westerly.

3. Label the following features on the attached surface (sea level pressure) and 500 mb height
maps for November 13, 2003 (on the next two sheets of paper).
a. On the sea level pressure map, label the surface lows with an L, and surface highs with an

H.
b. Draw arrows denoting wind speed and direction at points (A), (B), (C) and (D) on the sea

level pressure map. Be that the length of the arrows is representative of the wind speed.
c. For points (A) and (C), draw arrows that denote the pressure gradient force, the Coriolis

force, and friction. Be sure that the length of the arrows represents the strength of the
force.

d. Where do you expect the fastest winds to occur at the surface, at point (A), (B), (C) or
(D)? What two forces act to alter the wind speed at that point? What force does not alter
the wind speed at that point?

e. What sort of weather do you think Madison experienced on November 13, 2003? Briefly

explain.

f. On the 500 mb height map, label trough axes with a solid line, and ridge axes with a

dashed line.
g. Draw arrows denoting wind speed and direction at points (1), (2), (3) and (4) on the 500

mb height map. Be sure that the length of the arrows is representative of the wind speed.
h. For points (1) and (3), draw arrows denoting the pressure gradient force and Coriolis

force. Be sure that the length of the arrows represents the strength of the force.
i. Where do you expect the fastest winds at 500 mb, at point (1), (2), (3) or (4)? Why?

j. Label regions where you expect upper level convergence and divergence relative to the
troughs and ridges in the 500mb height map.

k. Based on the location of upper level divergence and convergence, do you expect the
surface cyclone to intensify (low pressure gets even lower) or die off (pressure rises in
the low)? Briefly explain why.

Sea Level Pressure

A

A
A

B

C

D

500 mb Height

1

2

3

4