SAN
FRANCISCO STATE UNIVERSITY Meteorology
430 DEPARTMENT OF GEOSCIENCES Fall
2010

Exam #1

250 Points

Name _______________________________________________

1. For
questions involving use of equations or calculations, lay out all equations carefully,
show all units, show all steps, number equations sequentially.

2. For
questions involving analysis or mapping techniques, use proper color conventions,
use proper mapping techniques (NO grease pencil on final copies).

3. This
examination is open book, open notes.

4. Answer
on separate sheets or on back of exam.

Part
A. **Map Set 1 (70 pts)**

1, Attached find the WXP analyses of 200
mb and 1000 mb convergence and 500 mb vertical velocities (in x, y, p
coordinates) forecast by the NAM 12Z 21 October 2010. Note the location indicated by the square off the California
coast.

The
simplified continuity equation is

(1)

**Assuming Dines Compensation, compute
the vertical velocity at 500 mb that would be associated with the divergence at
200 mb. (40 pts)**

You
will note the following:

(a) the
200 mb is near the tropopause and the divergence at the point at that
level is 1.0 X 10^{-5} s^{-1};

(b) 200 mb
divergence is representative of the net divergence in the layer from the Level
of Non- divergence
(LND) to the tropopause;

(c) the
vertical velocity at the tropopause is zero;

(d) the
tropopause is at the 200 mb level (11880 m) and the LND is at the 500 mb level (5700 m).

(e) the
1000 mb divergence at the same point is -4.25 X 10^{-5} s^{-1}_{ }(Note: it is not necessary to know this to
answer this question, but it will help you in forming your answer for (2)
below.

Show all work and lay out all steps.

2**. Briefly** explain to what extent the
charts given in Map Set 1 GENERALLY
illustrate the principle of Dines Compensation (at the location where
the small box is drawn). (25 pts)

3. **Print the following (starting at 8:30AM) for the date, time, and region indicated
on the black board: 42.5N, 130W, 48 hr forecast if you are doing a forecast
chart. Several of you will
be printing charts for 12 UTC today and don't need the latitude and longitude
information (10 pts)**

Vanessa |
500 mb
vertical velocity |

Alexandria |
300 mb
chart with observations (12 UTC 10/22/10) |

Denise |
200 mb
convergence |

Leo |
500 mb
chart with observations(12 UTC 10/22/10) |

Jacqueline |
200 mb
vertical velocity |

Matthew |
1000 mb
vertical velocity |

Ruisi |
Simple
surface chart with observations (12 UTC 10/22/10) |

Benjamin |
700 mb
chart with observations(12 UTC 10/22/10) |

Christopher |
850 mb
chart with observations(12 UTC 10/22/10) |

Hsiao-Yuan |
700 mb
vertical velocity |

Xiu Ping |
1000 mb
convergence |

Map Set 1

Part
B. **Map Set 2 (60 pts)**

Attached
find the 850 mb, 700 mb, 500 mb and 200 mb charts for12Z 22 October 2004. Also
included is the Eta initialization for surface isobars and 1000-500 mb
thickness.

**1. Discuss
why the trough over the central portions of the country ÒtiltsÓ towards the
west (in this case).**

**2. Draw
advection arrows and fronts for the cyclone in the midsection of the country.**

Map Set 2

Part
C. **Map Set 3 (80 pts)**

Attached
find sfcplot and a plot of unanalyzed surface observations for 12Z 22 October
2004

**Analyze the surface plot inside the
solid lines, using proper isobar intervals, color conventions, frontal/trough
symbols etc. (no isotherms or isodrosotherms). Use the 1000-500 mb thickness analysis from Part B to help
you to complete the frontal analysis. (70 POINTS)**

Map Set 3

Part
D. **Map Set 4 (40 pts)**

Attached
find the 12UTC soundings for Davenport, Iowa and Albuquerque, New Mexico; and
the surface isobars and 1000/500 mb Thickness for 12Z 22 October 2004.

Do
the following sets of questions:

1. Note the locations of Albuquerque
and Davenport labeled A and B, respectively.

**(a) Plot
the 1000 mb geostrophic wind vector at each location with a solid arrow. (You
will have to qualitatively estimate the length of the vector).**

**(b) Plot the thermal
wind vector at the same locations with dashed arrows. (Again, you will have to qualitatively estimate the length
of the vector..make it 4 times the length of the 1000 mb geostrophic wind
vector you did in (a)).**

**(c) Now,
on the back of this sheet, replot these vectors in a manner that will allow you
to estimate the 500 mb geostrophic wind vector. Replot the 500 mb geostrophic
wind vector on the map.**

2. **Describe how the thermal structure and wind
profiles evident on the sounding/wind plot for Davenport and Albuquerque is
consistent with your frontal analyses.**

**
**

Map Set 4