### ATMS 411/611 Atmospheric Physics [main page] [homework] [2020 notes] [2019 notes] [2018 notes] [2017 notes] [2015 notes] [2010 notes].

Week 6: 27 September

Tuesday and week in summary

Preparation:
Read problem 3 and work on the first problem as you read the chapter.

Continue with homework problems 2 and 3 discussion.
Water vapor mixing ratio on skewT diagrams (labeled version, unlabeled version)
Normand's rule

Hydrostatic equation.

Variation of g with altitude.

Geopotential.

Thickess of atmospheric layers.

Hurricane problem discussion, problem 4 of homework.

Related Information:

Week 5: 20 September

Tuesday and week in summary

Preparation:
Read problem 3 and work on the first problem as you read the chapter.

Chapter 3 topics
We will have several homework assignments from this especially important chapter.
The goals (learning and review objectives)

a. Ideal gas equation applied to dry and moist air.
b. Virtual temperature.
c. Potential temperature.
d. Hydrostatic equation.
e. Increasingly detailed description of the temperature and pressure distribution in the atmosphere.
f. SkewT logP diagrams.
f-g. Relative humidity, absolute humidity.
g. Dew point temperature.
h. Wet bulb temperature.
i. Equivalent potential temperature.
j. Latent heat release and absorption in condensation and evaporation of water.
k. Stability of air parcels.
l. Indices on soundings.
m. Brunt–Väisälä frequency and gravity waves.
o. Sound propagation in the atmosphere.
p. Hurricane thermodynamics and dynamics.

Wednesday

Water vapor discussion continued.
Saturation vapor pressure over ice and water at the same temperature.
Supersaturation and mixed phase clouds.
Aircraft icing discussion (deicing fluids include antifreeze, ethylene glycol).

Kinetic theory of pressure, relation to molecular speed and average kinetic energy PV=KE.

Water vapor gas constant. And the ratio of water vapor to dry air molecular mass, ε=0.622.

Thursday

Discussed project tools and Reno's minimum air temperature in summer over time. (first 3 subjects)

Virtual temperature.

Water vapor mixing ratio.

Friday

In-class lab day.
Measure temperature, wet bulb temperature, and pressure and get properties of the atmosphere.
Homework problem 3 discussion.
Water vapor mixing ratio on skewT diagrams (labeled version, unlabeled version)
Normand's rule

Hydrostatic equation.

Variation of g with altitude.

Geopotential.

Thickess of atmospheric layers.

Hurricane problem discussion, problem 4 of homework.

Related Information:

Week 4: 13 September

Tuesday and week in summary

Make progress on homework assignment 2 over the weekend.
Bring questions to class.
Cloud storage for documents should be available through Google drive, if you don't already have cloud storage.

Discuss problem 1.6d in the homework, the distribution of water vapor and ozone in the atmosphere compared with N2, O2, and CO2
and can refer to the plots of pressure and temperature as a function of altitude.
Vertical structure of the atmosphere.

Calculate, graph, and discuss density, and water vapor density as a function of altitude.

Wednesday

Obtain the scale height of the first 2 km of the atmosphere from a trendline for a plot of ln(Pressure) vs height. See homework for theory.

Thursday

Review the scale height of the atmosphere determination.
Calculate the average temperature of the 0 km to 2 km layer from the scale height, and compare with the measured average virtual temperature.
Discuss this as a means of checking the measurement accuracy for temperature and pressure, and of the relationship between them.

Discuss slides 25 and 30, western US and global precipitation and circulation that gives rise to them.

Friday

Discuss homework 3

We will start Chapter 3 on the theory of atmospheric thermodynamics.

Preparation:

Chapter 3 topics
We will have several homework assignments from this especially important chapter.
The goals (learning and review objectives)

a. Ideal gas equation applied to dry and moist air.
b. Virtual temperature.
c. Potential temperature.
d. Hydrostatic equation.
e. Increasingly detailed description of the temperature and pressure distribution in the atmosphere.
f. SkewT logP diagrams.
f-g. Relative humidity, absolute humidity.
g. Dew point temperature.
h. Wet bulb temperature.
i. Equivalent potential temperature.
j. Latent heat release and absorption in condensation and evaporation of water.
k. Stability of air parcels.
l. Indices on soundings.
m. Brunt–Väisälä frequency and gravity waves.
o. Sound propagation in the atmosphere.
p. Hurricane thermodynamics and dynamics.

Related Information:

 18Z model 12Z sounding

Week 3: 6 September

Tuesday and week in summary

Be sure to do online homework 2.

Preparation: Read chapter 1 and read over homework assignment 2, especially problems 3 and 4.
Students should complete questions 1 and 2 in the homework by Tuesday before class.
We will use them for problem 3 (and others later).

Review problem 1.20 that we worked on last Friday.
Calculate the mass flux carried by the trade-winds, and the time for the entire atmosphere mass to pass through the tradewinds.
Discuss problem 4 in the homework associated with the seasonal variation in surface pressure in each hemisphere.

Wednesday

Discuss global surface pressure in summer and winter seasons for problem 4 in the homework.
Discuss how these data are obtained.

Problem 3 Comparison of meteorology near the equator and near the north pole.
Use Google Earth to scope the two sampling locations, Rochambeau French Guiana and Barrow Alaska.
Acquire the PNG soundings for this locations. Add them also to the MSword document.
Discuss how to caption figures in MSword and how to cross reference to them in the text.

Thursday

Discussed the Reno balloon Races as a current event in Atmospheric Physics, and application of Archimedes principle.
Calculated density and buoyancy for the balloon.

Discuss the structure of the report. Figures, captions, and text that describes what the figures show (discuss in class).
Import the sounding data into Excel. Graphed pressure, temperature as a function of height.

Friday

Start class by answering all questions about how to work with the data.
Be sure everyone is caught up and knows how to import sounding data and graph it.
Double check to make sure everyone is able to save their calculations.

Calculate, graph, and discuss density, and water vapor density as a function of altitude.

Emphasize development of publication quality graphics.
Be ready to go when class starts.

(Investigate the OneDrive issue by trying out this site. https://onedrive.live.com and logging in using NetID.)

Discuss slides 25 and 30, western US and global precipitation and circulation that gives rise to them.

We will start Chapter 3 on the theory of atmospheric thermodynamics after Chapter 1.

Related Information:

Week 2: 30 August

Tuesday and week in summary

Be sure to do online homework 1.

Bring questions about homework 1 to class, concerning the skewT lnP thermodynamic diagrams of the atmosphere.

Revisit briefly the exponential model for pressure discussion and scale height for possible changes in the jet stream as polar regions warm.

Tuesday
Cyclostrophic flow and hurricane wind speed from centrifugal and pressure gradient balance. Devastation due to hurricane Ida.
Composition of the atmosphere presentation, and temperature variation. (ppt)
Discuss the variation of CO2 with time and the likely consequences.

Wednesday
Start Discussion of Homework 2
Hurricane dynamics, simple model for winds.
Lapse rate discussion in general for problem 2.
Reno summer time morning and afternoon soundings discussed.

Thursday
Review sounding indices from Tuesday.
View the atmospheric boundary layer for 8/25/2021, and vertical motions (from the UNR doppler lidar in Physics, Dr. Lareau).
Discussed PM2.5 measurements on top of the Physics building and inside of it and noted the response time of the building.
Problem 1.12 Antarctica lapse rate discussion (see homework 2).

Friday
Review problem 4 Seasonal variation in surface pressure in each hemisphere.
Related example problem: Problem 1.20 Flow associated with trade winds near the equator and set up of homework problem 1.21. Slide 26 of presentation.
Satellite imagery showing the IR imagery for the tropical eastern pacific.
Earth School animation of the NOAA Global Forecast System (GFS) model output to view the intertropical convergence zone (ITCZ) and trade winds.
Discuss homework 2 problem 1.21 on seasonal pressure changes in the northern hemisphere.

Problem 3 Comparison of meteorology near the equator and near the north pole.
Login to your account with Excel, using your netID, to the computers in the classroom or at home, before class so you're ready to go when class starts.
(Students in class will need to first logout of Excel and log back in so that saving to your OneDrive works properly).

Related Information:

Vertical distribution of aerosol and vertical motions of the air above the Physics building example from lidar for 8/25/2021.

Vertical structure of the atmosphere.

It's hurricane season! Image and animation of the Eastern Pacific. Images from this very useful weather website.
Hurricane track.
Hurricane formation discussion.

Week 1: 23 August

Friday

SkewT lnP thermodynamic diagrams of the atmosphere and homework 1 set up in class.

Thursday

Exponential model for pressure variation with height, and relationship for scale height. Cold and warm air meet on the polar front; jet stream.
Composition of the atmosphere presentation, and temperature variation.
SkewT lnP thermodynamic diagrams of the atmosphere and homework 1 set up in class.

Wednesday

Discussed practical aspects of density and typical values, and mirages. (Thanks for the question).
Pressure and mass of the entire atmosphere calculated with the Python tool. Prepare by setting up an account.
Pressure in the ocean.
Exponential model for pressure variation with height, and relationship for scale height. Cold and warm air meet on the polar front; jet stream.
Composition of the atmosphere presentation, and temperature variation.

Tuesday

Introductions and pressure discussion using OneNote.

 Introductions -- each student introduce themselves. Webcampus for online homework assignments/reading. How to monitor smoke conditions, ATMS example Geostationary satellite loop for the western US Smoke forecast for our area.

 Required Textbook: Atmospheric Science: An Introductory Survey by Wallace and Hobbs. Companion site. Supplemental Textbook: A First Course in Atmospheric Thermodynamics by Grant W. Petty. Article on multiple scattering in the atmosphere. Free online Introductory Textbook for Atmospheric Science and local backup Skew T presentation for in class discussions and as a gif file to be used with Paint.

 Online Homework 1 is due 30 Aug 2021. See webcampus. This is based on MetEd. Online Homework 2 is due 6 Sept 2021. See webcampus. This is based on MetEd. Homework 1 is due 27 August, to be turned in through web campus. Homework 2 is due 13 Sept, to be turned in through web campus.

 The final project has been posted.

This class is:
One part lecture;
One part active class participation/activity involving atmospheric data from around the world;
One part study using online modules for atmospheric science education.

Mass of the atmosphere calculation using an online Python editor.
Overview Presentation: Atmospheric Science relies heavily on measurements and models!

Vertical structure of the atmosphere.

Related Information:

It's hurricane season! Image and animation of the Eastern Pacific. Images from this very useful weather website.
Hurricane track.
Hurricane formation discussion.

It's fire season too! Loyalton fire tornado!
Satellite imagery for 19 August 2020.
Satellite imagery for 20 August 2020 with IR detection of hotspots (NASA polar orbiting satellite).
Animated satellite imagery for 20 August 2020 from GOES 16 (NOAA geostationary satellite).

Fire and meteorology feedback: Air pollution in Reno on the 16th of August. Meteorology on the 15th and 16th of August. Note the difference in stability and boundary layer height.

Wind barbs. Click image for larger version.

Reminder of cause for the seasons.

The fountain in Pittsburgh PA and its rainbow.