UBC  ATSC 201 - Meteorology of Storms

Teaching Methods and Subjects

Teaching methods

In this course we use a flipped teaching method called "Just-in-Time Teaching" (JiTT).  It uses the following structure:

Twice each week:

  1. New Learning Goals are provided on the course web page.
  2. Textbook readings (from the free textbook online) are assigned to students as homework.
  3. Students write a 3- or 4-question online quiz in Canvas as homework based on their readings. (Each quiz is open for a week before it is due. Deadlines on th assignment web pages are always given as Pacific Time.)
  4. The instructor receives a summary of the quiz results and tailors his class presentation to needs of the most students.
  5. In class, clicker questions are used to motivate group interaction to enhance Peer Learning. 
  6. The instructor gives "mini" lectures in class for only those concepts for which students still have confusion.
  7. Students are responsible for understanding the material listed in the Learning Goals, which includes the readings and the in-class activities.
Once each week:
  1. Students are assigned homework problems over the weekend, based on the previous 2 sets of Learning Goals. 
  2. The students need to use Excel or similar software to find numerical answers and discuss their significance.  Their homework answers are submitted on line  (via Canvas) by the start of class on Monday each week (or Wednesday if Monday is a holiday at UBC).
  3. Storm videos and/or hands-on tutorials on how to use some of the meteorological tools (e.g., radar and satellite images) are shown in the Monday class (most weeks).
Each term:
  1. One open-book midterm exam.  Only the learning goals are tested.
  2. One open-book final exam.  Only the learning goals are tested.

Week - Subjects Covered

Weeks 1-2
Meteorological Thermodynamics Intro.
- meteorological conventions for wind, the scientific method, ips on problem solving, earth frameworks, time zones and UTC, thermodynamic variables (temperature, pressure, density) and their units, atmospheric vertical structure (layers of atmosphere), troposphere, tropopause, e-folding definition, scale heights, standard atmosphere, geopotential height, ideal gas law (eq. of state), hydrostatic equilibrium, hypsometric eq., moisture, latent heat, sensible heat, process terminology (e.g., isotherm, isobar, isohume, isotach), .

Thunderstorms - types (air mass, squall line, muticell, supercell, mesoscale convective complexes), life cycle of individual cells, supercell storms (classical, low precip, high precip), mesocyclones, components of a thunderstorm (anvil, flanking line, wall cloud), forward and rear-flank downdrafts, watches and warnings, thunderstorm safety, storm chasing tips.


Weeks 3-4 
Atmospheric Radiation
- Earth's orbit, sunrise and sunset, time zones, seasonal and daily effects, fluxes, radiation principles (propagation, emission, distribution), average daily insolation, absorption, reflection, transmission, surface radiation budget, long and short wave radiation, net radiation

Dynamics & Winds - height contours on isobaric surfaces, Newton's 2nd law of motion, Lagrangian & Eulerian momentum budgets, Coriolis parameter, forces, advection, pressure-gradient force, centrifugal and centripetal forces, Coriolis force, turbulent drag, gravity, full equations of motion, vorticity (relative, absolute, potential), winds (geostrophic, gradient, boundary layer, boundary-layer gradient, cyclostrophic), continuity and mass conservation, convergence & divergence, boundary-layer pumping, Rossby number.


Weeks 5-6  
- formation, origin of rotation, evolution, types and shapes, location in supercell thunderstorm, radar signature, wall cloud, tornadic winds (tangential wind vs. core pressure), duration, tracks, tornado families & outbreaks, non-supercell tornadoes (landspouts, gustnadoes, waterspouts, cold-air funnels), tornado distribution, intensity vs frequency, tornado alley, Fujita & Torro scales, storm-relative winds, vorticity (relative, absolute, potential), helicity, mesocyclones, swirl ratio, multiple vortex tornado, detection and warning, forecasting, tornado safety, tornado chasing.

Lightning, Thunder,  breakdown potential, electricity and charge, electrification of thunderstorms, lightning stroke components (stepped leader, return stroke, dart leader), negative vs positive strokes, lightning current, lightning detection networks, distribution and frequency of lightning, types (strokes, heat, bead, sheet, St. Elmo's fire), upper-atmosphere discharges (red sprites, blue jets, elves), thunder, shock waves, Snell's law, refraction of sound, lightning safety, 

Heat - fluxes, sensible and latent heat, Lagrangian heat budget (first law of thermo, lapse rate, adiabatic lapse rate), dry and moist adiabats on a thermo diagram, potential temperatures (plain, liquid-water potential, and equivalent), Eulerian heat budget, surface heat budget,

Weeks 7-8

Hail - hail damage swaths & impacts, hail formation (embryo, growth, path within supercell), hail detection and warning, usefulness of polarimetric radar, hail distribution and seasonal variation, hail seeding and suppression difficulties.

Thunderstorm Initiation & Intensity,  - – convective inihibition (CIN), triggering (lifting) mechanisms for thunderstorms, convective available potential energy (CAPE, surface-based, mean layer, most unstable), key altitudes (mixed-layer depth, LCL, level of free convection LFC, equilibrium level EL), daily thunderstorm cycle, thunderstorm forecasting, stability indices (lifted, K, total totals, SWEAT, etc.), 

Stability – environmental lapse rates, parcel static stability (unstable, neutral, stable), nonlocal stability methods, layer stability, conditional instability, buoyancy, Brunt-Vaisala frequency, dynamic stability, turbulence determination.

Moisture  -  vapor pressure, saturation, Clausius-Clapeyron eq., Teten's formula, boiling, supercooled water, mixing ratio, specific humidity, absolute humidity, relative humidity, dew-pont temperature, saturation level and lifting condensation level (LCL), wet-bulb temperature, Normand's rule, psychrometers, total water mixing ratio, Lagrangian water budget, isohumes.


Weeks 9-10  
Downbursts of Air, Gust Fronts -
heavy rain, downburst formation (precipitation drag, evaporative cooling), DCAPE, structure (microbursts, vortex rolls, gust fronts), intensity and location, detection, hazards to aviation, haboobs.

Global Circulation, Jet Streams & Rossby Waves - nomenclature, differential heating, Hadley cell, subtropical jet, meridonal temperature gradient, net heat transport by atmosphere and ocean, jet stream, jet streaks, troughs and ridges, upper-level divergence, development of lows and highs, 3-band general circulation, thermal wind relationship, thickness, thermal wind, baroclinicity, barotropic and baroclinic instability, beta plane, Rossby waves, long and short waves (basic concepts, not details), planetary waves, Rossby radius of deformation, geostrophic adjustment.


Weeks 11-12 
Air Masses and Fronts
- anticyclones (highs), characteristics of highs (subsidence, fair weather, light winds), air-mass types and formation, air-mass boundaries, frontal zones, surface fronts, horizontal and vertical structure (of cold and warm fronts), atmospheric cross sections, clouds and precip associated with fronts, geostrophic adjustment, mid-tropospheric fronts (occluded fronts), upper-tropospheric fronts (tropopause folds), dry lines.

Midlatitude Cyclones (Lows) - Bergen model, formation, evolution, tracks, intensity, seasonality, characteristics (central pressure, vorticity, vertical motion, bad weather), appearance in satellite images, behavior over Pacific near western Canada, midlatitude (extratropical) cyclones, cyclogenesis, lee cyclogenesis, conservation of potential vorticity, spin-up (vorticity tendency), upward motion (omega, jet-stream curvature, jet-streak divergence, ageostrophic wind), sea-level pressure tendency (mass budget, diabatic heating), cyclolysis, iso-surfaces and their utility (isentropic, isobaric).


Weeks 13 & 14
Hurricanes (Tropical Cyclones)
- characteristics (spiral bands, eye, eye wall), Saffir-Simpson intensity scale, damage, tracks and steering winds, seasonality, favorable and unfavorable environments, sea-surface temperature and depth, dynamics (triggering in easterly waves, spin-up and development), thermodynamics (warm core), hurricane decay mechanisms, central pressure vs max wind speed, hurricane structure (pressure, velocities, temperature, clouds), heavy rain, embedded thunderstorms, storm surge, forecasting hurricanes, case studies of hurricanes (Katrina, Isabel, The Perfect Storm, Juan, Ida), appearance in satellite and radar image, hurricane hunter data and photos in eye, hurricane hazards & safety.

West-coast weather - Pinapple express, outflow and gap winds, cyclone graveyard, Pacific data void, orographic precipitation, mountain waves.