The requirements are listed in the uploaded file but just needed help on these questions, particularly the first few with mapping the points on the hadley cell and calculating the relative humidity afterwards.
I. Relative Humidity
Let’s assume that a volume of air (A) at the base of the Hadley Cell at the equator (EQ) starts out
both very warm (say, 28° C) and nearly saturated (containing 21 g water per kg air). As the air
rises above the equator it cools to 1° C at the top of the cell (location B). Location C represents
the base of the cell at sea level after the air descends at ~30 degrees N or S latitude.
B
A
C
1. On the graph, plot and label points
corresponding to points A, B, and C using
the information provided above and what
you have learned from module 2.
2. On the graph, using a dashed line and
small arrows (
), sketch the
path (temperature & water content of air) of
the volume of air as it travels through the
Hadley Cell from points A to B to C.
3. Showing your work below, calculate the relative humidity of the volume of air at points A, B,
and C.
II. The Western U.S. and California Example: Does orographic precipitation really happen?
Here we will explore how the orographic effect influences (or not) precipitation patterns in the
western US.
1. Using the data table (last page of your lab), plot a topographic profile across California:
Topographic Profile
4000
WEST
EAST
3500
3000
El
e
v
at
io
n
(
m
)
2500
2000
1500
1000
500
0
123
122.5
122
121.5
121
120.5
120
119.5
Longitude
2. Now, plot the average annual precipitation along the same longitudinal profile below:
Precipitation
Aver
age
prec
ipitat
ion
(inc
hes/
year
)
70
WEST
EAST
60
50
40
30
20
10
0
123
122.5
122
121.5
121
Longitude
120.5
120
119.5
3. Discuss the patterns of precipitation from West to East. Are the data consistent with your
expectations based on the orographic effect?
Why are some locations at very high elevation relatively dry (e.g., Carson City or Topaz
Lake), whereas some locations at relatively low elevation are moderately wet (e.g.
Sebastopol)?
4. On the map of the Western US below:
A) Sketch the major mountain chains (Sierra Nevada, Rockies, Coast Ranges, etc…).
B) Indicate areas that you expect to have low, moderate, and high annual precipitation.
Think about both the orographic effect and global atmospheric circulation patterns.
Data Table for Part II
Location
Auburn
Big Canyon
Blue Canyon
Calaveras
Calistoga
Carson City (NV)
Davis
Echo Summit
Grizzly Flats
Napa
Placerville
Point Reyes
Sacramento
Sebastopol
Sonoma
Topaz Lake
Truckee
Volcanoville
Longitude
121.06
120.90
120.20
120.31
122.58
119.76
121.76
120.03
120.51
122.30
120.73
123.80
121.50
122.81
122.46
119.55
120.15
120.78
elevation (m)
387
259
1609
1430
112
1417
18
2240
1177
18
839
9
5
20
29
1537
1834
927
precipitation (in/yr)
38.5
32.8
67.7
54.5
37.4
11.2
17.3
50.8
48.9
24.1
39.9
25.5
17.4
31.6
29.5
8.4
32.1
45.9