ATMS 411 Homework [Main Page] [Daily Notes]

 

Homework style example.
Homework style example with a graph.

Homework 8 Read problem 6.8 first, page 263. Read chapter 6. Do problem 6.8 parts a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, q, s, t, u. It has many parts, so start early. This presentation lists the problems. Here are the problems.

Homework 7

ALL ATMS 411 and ATMS 611 STUDENTS

Problems 4.19, 4.21, 4.29, 4.56, and
4.41 with the additional question "What is the total transmission coefficient for the cloud including multiple scattering and what fraction of the total is diffuse radiation?" The asymmetry parameter, g, for cloud droplets is mentioned in the chapter. Assume the cloud droplets do not absorb solar radiation, and that the 1-D model given in the presentation for this chapter is applicable (sun overhead). Homework 7 problems are here.

On problem 4.19 it may be helpful to use the online calculator for solar angle and sun earth distance. Note, we are calculating the present day values of solar irradiance in summer and winter (the information on ice age is to highlight the importance of thinking about orbital mechanics between the sun and Earth in your climate thinking).

ATMS 611 STUDENTS ALSO DO ... [EXTRA CREDIT FOR ATMS 411 STUDENTS]

PROBLEM 4.55 and answer the question, what is a weighting function in the context of passive IR remote sensing, and how is it used? Hint: A useful reference for this problem is the book by Grant Petty, A First Course in Atmsopheric Radiation, chapter 8, the entire chapter.

Homework 6 READ problem 4.11 first, page 145. Read chapter 4. Do problem 4.11. It has many parts, so start early. This presentation lists the problems.

Homework 5 (Group mini projects)

Each group will present their homework. You only need to do the work with your group, not the entire set
Work in a way that each group member presents part of the problem.
It's best to use powerpoint for these problems.
Evaluation will be based on completeness, participation by each group member, and originality/creativity/thoughtfulness.

Group 1. REVISION: The role of each member is given below.

Obtain data from the DRI , UNR, and Slide Mountain weather stations (see below). Calculate the average virtual temperature for the layer between these stations using the hypsometric equation. Then calculate the virtual temperature at each of these stations, take the average value, and compare with the value you get from the hypsometric equation. Interpret. Make a graph of the average virtual temperature versus time for both of these methods. Also, make a scatter plot of the average virtual temperature from both methods, and compare using a linear regression model. Do so for July 2015. Obtain the elevation of each station from the site descriptions given below for use with the hypsometric equation. [THIS GROUP LINKS TO GROUP 6 AS WELL].

NOTE: The UNR site does not have data from 7/4/2015 at 9:20 through 7/7/2015 at 1:00. Remove these data from the DRI and Slide Mountain sites as well. You should have exactly the same number of points for each site so that time alignment is perfect.

Valerie: Calculates and compares average virtual temperature with hypsometric equation results for the UNR and DRI weather stations (preliminary results completed already). Give calculated results (graphs) to Jessica, and present during presentation.

Dillon: Calculates and compares average virtual temperature with hypsometric equation results for the UNR and Slide Mountain weather stations. Give calculated results (graphs) to Jessica, and present during presentation.

Devin: Calculates and compares average virtual temperature with hypsometric equation results for the DRI and Slide Mountain weather stations. Give calculated results (graphs) to Jessica, and present during presentation.

Jessica: Assembles the powerpoint presentation. Discusses virtual temperature and how it's obtained from both methods. Determine which pressure sensor is likely incorrect.

Group 2. Each person pick a morning and afternoon sounding from your favorite place/time in the world.
Thoroughly interpret your soundings. Learn about and interpret as many sounding indices as you can.

Group 3. Carefully define the sounding indices CAPE, CIN, and precipitable water.
Show how these are calculated (equations involved).
Find some exciting soundings with large CAPE, and interpret.
Do the calculation for these soundings for CAPE, CIN, and precipitable water to check the reported values. Presentation.

Group 4. Find a December in Reno where there were strong temperature inversions in the mornings as noted on the NWS balloon soundings. Define and display temperature inversions, and why they are so stable. Calculate the actual lapse rate from the data in the soundings; calculate the same from the UNR and DRI weather stations, compare as a time series your results by both methods. Presentation.

Group 5. Define the mixed layer depth. Compare and contrast the mixed layer depth from the afternoon soundings
in Mexico City, Reno, and a place in Florida. Discuss different methods used to obtain mixed layer depth and apply as many of them as you can.

Group 6. Show how to use data from the DRI and UNR weather stations (DRI sites). Calculate the average virtual temperature for the layer between these two stations using the hypsometric equation. Then calculate the virtual temperature at each of these stations, take the average value, and compare with the value you get from the hypsometric equation. Interpret. Make a graph of the average virtual temperature versus time for both of these methods. Also, make a scatter plot of the average virtual temperature from both methods, and compare using a linear regression model. Do so for a December month where we actually had winter (not last winter for sure). Presentation.

All of the Western Regional Climate Center Weather Sites click here  
LOCAL WEATHER STATION DATA MANAGED BY THE WESTERN REGIONAL CLIMATE CENTER AT DRI PASSWORD IS wrcc14 SITE DESCRIPTION Current Data Graphs to see what's going on
UNR Weather Station on Valley Road

click here
Accurate Coordinates:
39.53918 N, 119.80476 W

click here
DRI Weather Station click here click here
Slide Mountain Weather Station click here click here

Homework 4 To do in class: attendance mandatory, in class homework.

To do in class: attendance mandatory, in class homework.
Grades on webcampus for this assignment will change as you finish problems.

0. This problem was given in class. See the first board (click on it for larger version).
The second board describes how to work with the equivalent potential temperature.

1. Winter time dryness inside when it's cold outside.
Let Toutside=Tdew=-10 C, and Tinside=25 C.

a. Find the mixing ratio. (dashed line through Tdew)

b. Find the relative humidity inside. RH=100 * mixing ratio / saturation mixing ratio at inside temperature.

2. Measure the temperature and wet bulb temperature (Twb) in the classroom.
Find:
a. Lifting condensation level.
b. Tdew.
c. Theta. (dry adiabat through T to 1000 mb, and read temperature).
d. ThetaE (moist adiabat through LCL to TOA and back to 1000 mb along dry adiabat, read temperature).
click image for larger image.

3. Chinook winds, ascend Sierras from the west; precipitation; descend eastern side; find temperature.
SHOW THE TRAJECTORY ON THE PAPER VERSION OF THE SKEW T AVAILABLE IN CLASS. (This is what you'll turn in.)
FIRST WORK IT OUT USING THE LAMINATED SHEETS.

Taken from example 3.10.
Start at 950 mb, 14 C, 8 g/kg.
Ascend to 700 hPA. Let 70% of precip fall out, 30% remain with air parcel.
Descend to 950 mb and find the temperature and wet bulb potential temperature; compare with initial values.

Should find:
Initially wsat(T)=10.6 g/kg; Show that LCL=890 mb; ThetaW=14 C. Continue to 700 mb and should find Wsat=4.7 g/kg.
Amount of condensed water at 700 mb = 8 g/kg - 4.7 g/kg = 3.3 g/kg.
30% of 3.3 g/kg = 1 g/kg.
Parcel descends on moist adiabat until reaching a mixing ratio of 5.7 g/kg (at 760 mb), and then dry adiabat to 950 mb.
Final temperature is 20 C, mixing ratio is 5.7 g/kg.
Final wet bulb potential temperature is 14 C.

Note: 'Chinook wind' in this example results in T = 20 C, 6 C warmer than the beginning temperature,
with the extra heat due to the latent heat release during ascent, and that most of the condensation falls out.

Homework 3a. Having read chapter 3:
1. Make your own skew T log P graph using Excel.
Place the lines on it for temperature, mixing ratio, dry and moist adiabats.
Find a sounding (using the UWyoming sounding server) with considerable CAPE. Plot this sounding on your skew T log P graph.
Show the equations for, and calculate, the CIN and CAPE for your sounding. Compare with what the UWyoming sounding shows.
Why "to have CAPE, there must be CIN"? Given that, how can we ever have strong thunderstorms?
Choose one other index from the UWyoming sounding. Define and discuss it, and calculate it for your sounding.

2. Observe soundings for 1 week (twice per day) for a location of your choice within the US.
Calculate the sounding based on this model. Play with it to choose the most effective resolution and model for your location.
You will have to capture the frame that corresponds to the time of your sounding.
Good choices might be a mountainous region like Reno, or a very topographically flat area by comparison.
Compare your soundings side by side and discuss the difference between model and measurements.

 

Homework 3. Having read chapter 3:
Problems page 1, page 2.
1. Do problem 3.20.
2. Read problem 3.21 carefully. Do problem 3.23
3. Do problem 3.38 .
4. Read problem 3.30 carefully. Do problem 3.31.
5. Do problem 3.35.
6. Read problem 3.36 carefully. Do problem 3.39.

Group 1 will present problem 1; group 2, problem 2; and so forth.
Everyone will turn in all problems.

Homework 2. Read chapter 3. Do problems 3.18, 3.19, and 3.26

GROUPS:
Group 1: Jessica
Group 2: Jason
Group 3: Deep
Group 4: Sebastian
Group 5: Zoey
Group 6: Sam


Group 1 presents 3.18 a, b, c, d
Group 2 presents 3.18 e, f, g, h
Group 3 presents 3.18 i, j, k, l
Group 4 presents 3.18 m, n, o, p
Group 5 presents 3.18 q, r, s, t
Group 6 presents 3.18 u, v, w, problem 3.19

Homework 1. Read chapter 1. Do problems 1.6, 1.7, 1.11, 1.12, 1.13

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