UBC  ATSC 201 - Meteorology of Storms

Learning Goals


Aim



Course Goals

By the end of this course, you should be able to:



Lecture Goals for 2022

Use the Assignments link to find the learning goals for each lecture period, as listed week by week.  They are also summarized below:

Monday Wednesday Friday
5 Sep.

Holiday
7 Sep.  (W1D3)
Topics: Welcome, Meteorological Conventions, JiTT Methods,  Thunderstorm Intro.
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Learning Goals
At the end of this section, you should be able to:
  1. Find the weekly learning goals and assignments from the course web page.
  2. Visually recognize fundamental aspects of thunderstorms.
  3. Explain to your friends the value of Just-in-Time Teaching (JiTT) and Peer Instruction.
  4. Explain how the differences between meteorological and mathematical coordinate systems alter the way you use trig., and convert wind from Cartesian to speed and direction.
  5. Create and use graphs where the independent variable (height, or pressure-as-a-surrogate-for height) is plotted on the vertical axis.
9 Sep. (W1D5)
Topics: Meteorological Variables, Basic Thermo, Standard Atmos. & Excel Demo #1
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Learning Goals
At the end of this section, you should be able to:
  1. Convert between any time zone and UTC.
  2. Plot the average variation of air pressure, temperature, and density with altitude, and explain why they vary that way.
  3. Contrast geopotential height with geometric height.
  4. Name the layers and levels in the atmosphere, and summarize their main characteristics.
  5. Clearly describe and solve numerical problems using tools like Microsoft Excel.
Also, for your homework over the weekend:
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Learning Goals
At the end of this section, you should be able to:
  1. Apply topics covered earlier this week to compute number answers & infer their significance.  
  2. Refine your ability to use programs like Excel to solve scientific problems.
  3. Develop good problem-solving habits, such as clearly stating the problem and unknowns, and including units with your calculations.
  4. Experience some of the pitfalls of solving number problems such as mismatched units, and be able to diagnose and fix your errors.

12 Sep.  (W2D1)
Topics: Basic Thermo & Hydrostatic Relationships, Excel Demo #2.
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Learning Goals
At the end of this section, you should be able to:

  1. Describe the physical concepts behind the equations of state, hydrostatic, and hypsometric, and be able to use them.
  2. Relate the "iso..." names to the atmospheric processes that they represent.
  3. Explain what the virtual temperature represents, & be able to compute it and use it.
  4. Use Excel confidently for most meteorological numerical problems and graphing.
14 Sep.  (W2D3)
Topic: Thunderstorm Characteristics & Types (including Supercells)
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Learning Goals
At the end of this section, you should be able to:
  1. Visually recognize thunderstorms and identify their cloud components.
  2. Describe the stages in evolution of a thunderstorm cell.
  3. Compare & contrast basic storms vs. supercell storms.
  4. Explain how different types of supercell storms work.
16 Sep.  (W2D5)
Topic: Thunderstorm Mesoscale Convective Systems (MCS), Radar Fundamentals & Storm Chasing Tips
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Learning Goals
At the end of this section, you should be able to:

  1. Compare and contrast MCS storms with other  thunderstorm types.  
  2. Summarize how a weather radar operates.
  3. Interpret radar reflectivity info to diagnose rainfall intensity.  (Z-R relationships)
  4. Explain the range and velocity limitations of weather radar. (start today, finish on Monday)
  5. Make sound decisions when you chase and photograph severe storms.

19 Sep.  (W3D1)
Topic: Radar image interpretation
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Learning Goals
At the end of this section, you should be able to:

  1. Find real-time radar images and loops on the web.
  2. Interpret the types of information in a radar reflectivity display.
  3. Look at a radar reflectivity image and determine thunderstorm location, movement, type, rainfall intensity.
  4. Interpret Doppler radar images to estimate wind velocities and identify tornado vortex signatures (TVS), mesocyclones,  downbursts/gust-fronts, and supercells.
21 Sep. (W3D3)
Topic: Atmospheric Radiation
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Learning Goals
At the end of this section, you should be able to:

  1. Explain how sunlight reaching the earth is affected by earth orbital characteristics.
  2. Convert between dynamic and kinematic fluxes.
  3. Apply principles from basic physics to determine the amount of radiation to and from the earth in the two main wavelength bands of interest:  visible and infrared.
  4. Explain the meaning of the terms in the surface radiation budget.
23 Sep .  (W3D5)
Topic: Forces Acting on the Air
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Learning Goals
At the end of this section, you should be able to:

  1. List the horizontal forces that can act on the air.
  2. Explain how to quantitatively determine the magnitude and direction of each force.
  3. Use weather maps to qualitatively to anticipate the direction and relative magnitudes of many of the forces.
  4. Explain how Coriolis force works.

26 Sep. (W4D1)
 Topic: Hodographs
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Learning Goals
At the end of this section, you should be able to:

  1. Plot wind profiles on blank hodographs, and interpret plotted hodographs.
  2. Explain how wind shear enables severe thunderstorms.
  3. Determine thunderstorm movement from hodograph plots.
  4. Be safe if you chase thunderstorms.
28 Sep. (W4D3)
Topic: Winds & Continuity
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Learning Goals
At the end of this section, you should be able to:

  1. List the names of the horizontal winds, and describe which forces affect them.
  2. Describe and calculate the geostrophic wind.
  3. Compare other winds to the geostrophic wind, concerning their direction, magnitudes, and where they apply.
  4. Look at weather maps to diagnose wind speeds and directions.
  5. Anticipate time and space scales for various atmospheric phenomena.
  6. Explain why air density increases when winds blow more air molecules into a volume than out.
  7. Anticipate how winds diverge in one direction in response to convergence in other directions, such as at a thunderstorm anvil.
30 Sep. (W4D5)
Holiday

In other terms when today is not a holiday, we cover these topics: Continuity & Vorticity
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Learning Goals
At the end of this section, you should be able to:

3 Oct.  (W5D1)
Topic: Tornadoes
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Learning Goals
At the end of this section, you should be able to:

  1. Visually  recognize and identify tornadoes and associated wall clouds.
  2. Visually determine the life-cycle stage of a tornado and anticipate its subsequent evolution.
  3. Classify the different types of tornadoes.
  4. Propose how to safely chase and photograph tornadoes.
  5. Classify tornado strength using the Enhanced-Fujita scale.
5 Oct. (W5D3)
Topic: Tornadoes, Vorticity & Helicity
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Learning Goals
At the end of this section, you should be able to:

  1. Distinguish between the rotational and translational velocities of a tornado, and explain the forces that drive these motions.
  2. Explain how thunderstorms get rotation, and describe the rotation is enhanced.
  3. List and calculate the different types of vorticity, and describe how they relate to each other.
  4. Apply the concept of potential vorticity conservation to determine changes in relative vorticity.
  5. Describe the forces that cause changes in vertical velocity.
  6. Apply the concepts of helicity and storm-relative helicity to explain severe storm evolution.
  7. Determine helicity from a hodograph.
  8. Relate swirl ratio to the existence and characteristics of multiple-vortex tornadoes.
7 Oct. (W5D5)
Topic: Lightning & Thunder - Part 1
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Learning Goals
At the end of this section, you should be able to:

  1. Contrast theories for how thunderstorms  become electrified.
  2. Describe the evolution of a lightning stroke.
  3. List the different types of lightning, and judge which are most hazardous.
  4. Explain how lightning creates thunder.
  5. Criticize the hypothesis that you can't hear thunder beyond a certain distance.
10 Oct.

Holiday
12 Oct. (W6D3)
Topic: Lagrangian Heat Budget
At the end of this section, you should be able to:
  1. Contrast the nature of different types of lapse rate.
  2. Contrast adiabatic vs. diabatic processes.
  3. Forecast the temperature change of an adiabatically rising or sinking air parcel.
  4. Plot dry adiabats on a thermo diagram, and demonstrate how to use a thermo diagram to easily forecast temperature change of rising or sinking air parcels without doing calculations.
  5. Interpret the meaning of the potential temperature and virtual potential temperature, calculate them, and relate them to plotted adiabats.
14 Oct. (W6D5)
Topic: Eulerian Heat Budget
At the end of this section, you should be able to:
  1. Distinguish between the Eulerian and Lagrangian heat budgets, and to recommend when to use each type.
  2. Explain what each term in the Eulerian heat budget represents physically.
  3. Forecast air temperature if you know the values of the Eulerian heat-budget terms.
  4. Describe the terms in the surface heat budget, and explain how that budget relates to the surface radiation budget.
17 Oct. (W7D1)
Topic: Hail, and Lightning & Thunder - Part 2
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Learning Goals
At the end of this section, you should be able to:

  1. Summarize key aspects of the distribution of lightning around the world.
  2. Relate lightning hazards to lightning characteristics.
  3. Recommend actions you can take to make yourself safe near a thunderstorm.
  4. Explain how hailstones are formed.
  5. Recognize hail indicators in weather radar.
  6. Take action to be safe if a hailstorm approaches.
 



 
19 Oct. (W7D3)
Moisture: Saturation, Variables, Diagrams 
At the end of this section, you should be able to:
  1. List the names, define, and explain how to use each moisture variable.
  2. Calculate the humidity and saturation values for any moisture variable.
  3. Distinguish between moisture content and saturation.
  4. Explain why cooling can cause water vapour to condense.
21 Oct. (W7D5)
Moisture Budgets: Lagrangian & Eulerian.
At the end of this section, you should be able to:
  1. Describe the concept of an air parcel, and explain what is conserved when it rises.
  2. Use dry and moist adiabats, and isohumes, on a thermo diagram to forecast the change of thermodynamics state of moving air parcels.
  3. Contrast different potential temperatures, and be able to calculate them.
  4. Explain the physical meaning of each term in the Eulerian moisture budget.
  5. Read weather maps of humidity to infer likely locations for thunderstorm development.

24 Oct. (W8D1)
Thermo Diagrams - Part 1: Components, Types, & Thermo State
At the end of this section, you should be able to:
  1. Summarize the different types of lines that are normally drawn in a thermo diagram.
  2. Look at a thermo diagram and identify and label each type of line.
  3. Summarize the different types of thermo diagrams that are used around the world.
  4. Identify the type of thermo diagram by looking at the arrangement of lines on it.
  5. Use the lines in a thermo diagram to determine the thermodynamic & moisture state of air.
26 Oct. (W8D3)
Thermo Diagrams - Part 2: Applications
At the end of this section, you should be able to:
  1. Use thermo diagrams to forecast how air state changes due to processes including: lifting, precipitation, and radiative heating/cooling.
  2. Use thermo diagrams to determine the lifting condensation level (LCL) -- which is cloud-base height for thunderstorms.
  3. Explain how buoyancy of an air parcel depends on both its thermodynamic state and the state of the surrounding environment.
  4. Define the Brunt-Vaisala frequency, and explain how it relates to the environmental state, and calculate it.
28 Oct. (W8D5)
Thermo Diagrams - Part 3:
Soundings, Static Stability, and CAPE
At the end of this section, you should be able to:
  1. Determine static stability from sounding plots on thermo diagrams.
  2. Estimate the heights of the boundary layer, level of free convection, equilibrium level, and tropopause from sounding plots on thermo diagrams.
  3. Explain the role of the lid or cap, and how thunderstorms can be triggered.
  4. Define CAPE and CIN, and explain what they physically represent.
  5. Look at a sounding and recognize the CAPE and CIN areas.
  6. Know how to use stability indices to forecast thunderstorms.

31 Oct.  (W9D1)
Downbursts & Gust Fronts
At the end of this section, you should be able to:
  1. Describe the conditions needed for downbursts to form.
  2. Anticipate the behavior of downbursts and gust fronts.
  3. Explain the hazard of gust fronts to aircraft & structures.
  4. Look at arc clouds, haboobs & Doppler radar to recognize the downburst/ gust-front hazard, and take appropriate action to be safe.
  5. Relate the fundamentals that you learned earlier in this course to the favorable conditions needed for thunderstorm formation.
  6. Normand's Rule, for estimating wet-bulb temperature Tw.
  7. The utility of CAPE for predicting Storm hazards.
 
2 Nov. (W9D3)
Midterm Exam - In class .
(or if virtual due to pandemic, then exam on Canvas with Zoom invigilation)
   (open books, open notes, open laptop)
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Learning Goals
At the end of this section, you should be able to:

  1. Demonstrate on the exam that you have synthesized all the material covered into a coherent understanding of:
       a) thunderstorms,
       b) atmospheric thermodynamics,
       c) atmospheric dynamics.
  2. Be proficient at using the following tools:
       a) hodographs,
       b) thermo diagrams,
       c) weather radar images.
  3. Use equations to calculate and interpret quantitative results.
Hint: for a list of all the reading assignments that will be covered on the midterm exam, go to the Assignments link and select Week 9 (Wednesday).
4 Nov. (W9D5)
Global Circulation - 1:  
Description, Differential Heating,
Thermal Circulations,  Geostrophic Adjustment

Learning Goals
At the end of this section, you should be able to:
  1. Use the global-circulation nomenclature and jargon (e.g., zonal, mereridional, extratropical, etc.)
  2. Describe and name the dominant horizontal general-circulation flow patterns at the surface, including monsoonal flows.
  3. Explain the Hadley cell: where it is, what it does to the atmosphere, and how it is connected to the surface flow patterns.
  4. Use LeChatelier's Principle to explain how differential heating drives the global circulation.
  5. Explain how each of the following dynamical processes works:
    a) hydrostatic thermal circulations
    b) geostrophic adjustment
    c) the thermal wind relationship (continued next week). 
7 Nov. (W10D1)
Topic: Tutorial on Cloud Identification & 
General Circulation 2: Thermal Wind 
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Learning Goals for Cloud Identification
At the end of this section, you should be able to:

  1. Look at clouds and classify them into stratiform, cumuliform, or special.
  2. Look at normal clouds and identify/name them.
  3. Relate what you see with your eyes to what weather radars and satellites see.
  4. Be able to use high-dynamic-range (HDR) photography to take better cloud photos with your mobile device.

Topic (in last 20 minutes): General Circulation2: Thermal Wind. 
(See the thermal-wind goals listed from the previous class.) 

9 Nov.

Holiday - Fall Break
11 Nov.

Holiday - Fall Break
14 Nov. (W11D1)
Topic: Tutorial on Weather-Satellite Image Interpretation
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Learning Goals
At the end of this section, you should be able to:

  1. Explain how weather satellites use radiation to remotely observe the earth.
  2. Categorize the main types of weather satellites in orbit.
  3. Compare capabilities and drawbacks of each imager channel, andexplain why it is advantageous to use multiple channels.
  4. Retrieve satellite images from the web and interpret them to diagnose the clouds and weather.
16 Nov. (W11D3)
Topic: Global Circulation - 3:   Jet Streams and Rossby Waves
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Learning Goals
At the end of this section, you should be able to:

  1.  Compare the driving forces of the subtropical jet and the polar jet.
  2. Explain how jet stream strength and location varies with season.
  3. Explain why the variation of Coriolis force with latitude causes the restoring force that drives the Rossby wave.
  4. Compare the speed of short and long Rossby waves.
  5. Look at a weather map of the mid or upper troposphere, identify where the jet stream is, and forecast the speed and movement of the troughs and ridges of different wavelengths.
  6. Synthesize all processes involved in the global circulation to explain why the Earth's atmosphere has 3 dominant circulation bands in the N. Hemisphere, rather than one big Hadley cell.
18 Nov. (W11D5)
Topic: Airmasses & Fronts -part 1
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Learning Goals
At the end of this section, you should be able to:

  1. Locate on a map the favored formation region for the following airmasses near N. America:  cP, cT, mP, mT, cA, and explain why airmasses have favored formation regions at all.
  2. Contrast a ridge and a high-pressure center, and compare them to troughs and low-pressure centers.
  3. Recognize warm, cold, and occluded fronts on weather maps.
  4. Anticipate the weather changes associated with passage of each type of front.
  5. Synthesize you knowledge of clouds and fronts to be able to look in the sky and make a weather forecast based on the clouds that you see.



21 Nov. (W12D1)
Topic: Synoptic Weather Maps &  Isoplething Tutorial
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Learning Goals
At the end of this section, you should be able to:
  1. Decode a station plot model
  2. Analyze isobars and isotherms on a weather map, and identify frontal zones and airmasses.

23 Nov. (W12D3) Topic: Fronts - part 2,  and
Extratropical cyclones - part 1: Characteristics & Evolution

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Learning Goals
At the end of this section, you should be able to:

  1. Using vertical cross sections, contrast warm and cold fronts and  occlusions.
  2. Explain how geostrophic adjustment affects fronts.
  3. Describe the characteristics of upper-tropospheric fronts
  4. Compare and contrast dry lines with fronts.
  5. Synthesize your knowledge of fronts (including dry lines and gust fronts) with your knowledge of thunderstorm triggering to explain why some fronts are favored locations for thunderstorms.

  6. Draw diagrams showing how fronts change around an evolving cyclone.
  7. Catalog favored cyclogenesis regions, and explain why they are favored.
  8. Explain why cyclones can intensify in spite counteracting effect of  boundary-layer winds.

25 Nov. (W12D5)

Topic: Extratropical Cyclones - part 2:
Cyclogenesis
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Learning Goals
At the end of this section, you should be able to:

  1. Diagnose cyclone location, movement, and evolutionary stage from satellite imagery.
  2. Recognize cyclones in upper-level isobaric charts as well as surface charts.
  3. Form a picture in your mind of the 3-D structure of extratropical cyclones, especially of the tilting of the low center with height.
  4. Anticipate weather hazards associated with cyclone passage.

  5. Describe how lee cyclogenesis works, and explain why it is so important to weather in N. America.
  6. Explain the processes that can increase the vorticity  of a midlatitude cyclone.(i.e., spin up)
  7. Justify why divergence aloft is necessary for cyclogenesis.
  8. Demonstrate how jet-stream curvature and jet-streak characteristics can create the needed divergence aloft.
  9. Qualitatively interpret the terms in the net pressure tendency equation.

28 Nov. (W13D1)
Topic: Extratropical Cyclones - Part 3: Case Studies 
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Learning Goals
At the end of this section, you should be able to:

  1. See examples of evolving cyclones in the Northern Hemisphere. 
30 Nov. (W13D3) 
Topic: Hurricane Characteristics, Structure & Evolution
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Learning Goals
At the end of this section, you should be able to:

  1. Describe the size and components of hurricanes.
  2. Categorize hurricanes, cyclones, and typhoons into their proper oceans.
  3. Describe the trigger mechanisms for hurricanes.
  4. Explain how hurricanes intensify, and what controls their movement.
  5. Relate the Saffir-Simpson wind scale to winds and destructiveness.
  6. Explain why hurricanes can't cross or form at the equator.
3 Dec. (W13D5)
Topic: Hurricane Dynamics & Thermodynamics 
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Learning Goals
At the end of this section, you should be able to:

  1. Explain why warm sea-surface temperatures are needed.
  2. Explain what causes hurricanes to die.
  3. Explain why hurricanes need a warm core to exist.
  4. Relate the winds to the dynamics and thermodynamics of hurricanes.

5 Dec. (W14D1)
Topic: Hurricane Models, Climatology, Hazards & Forecasting
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Learning Goals
At the end of this section, you should be able to:

  1. Describe the fundamental processes that explain how winds, pressure, and temperature are related to each other in hurricanes.
  2. Predict hurricane strength and track using numerical models, conceptual models, and climatology.
  3. Explain hurricane hazards and safety procedures to the general public.
  4. Compare and contrast tropical vs. extratropical cyclones.
7 Dec. (W14D3)
Topic: West Coast Weather & Course Review.

Learning Goals
At the end of this course, you should be able to:

  1. Describe west-coast weather phenomena including: pre-frontal jets, the pineapple express (aka atmospheric rivers), the cyclone graveyard, orographic precipitation, instant occlusions upon landfall, polar lows, etc.
  2. Formulate in your mind a coherent picture of how the different weather phenomena discussed in class relate to each other.
  3. Compare the relative skill in forecasting these different phenomena.  
  4. Judge the value of spending tax dollars on improvement to weather forecasting.
  5. Identify the different subdisciplines within meteorology, and list which ones we covered and which we didn't.
(Date to be set by UBC Registrar)
Final exam
The final exam is comprehensive (covers the whole course), but most of the questions are based on all the material since the midterm exam. .
Learning Goals
Based on all the material since the midterm exam, you should be able to:
  1. Synthesize all the material you learned into a coherent understanding of:
    1. general circulation (global climate, jet streams, Rossby waves)
    2. synoptics (air masses, fronts, mid-latitude cyclones)
    3. hurricanes
  2. Be proficient at using the following tools:
    1. weather satellite images
    2. weather maps
  3. Be able to look at the sky and:
    1. identify the clouds
    2. make a short-term forecast (nowcast) for the local weather
(a review session will be scheduled later.)