Meteorology and Climate Science Review

A comprehensive set of flashcards covering key concepts from meteorology, including mid-latitude cyclones, thunderstorms, tornadoes, hurricanes, air pollution, and climate change.

What is a mid‑latitude cyclone?

A large‑scale low‑pressure system that forms between 30°–60° latitude and is associated with fronts and strong temperature contrasts.

In which direction do mid‑latitude cyclones usually move?

West to east, steered by the prevailing westerlies.

What key boundary is associated with mid‑latitude cyclone formation?

The polar front, which separates cold polar air from warm tropical air.

How does a mid‑latitude cyclone initially develop?

As a wave disturbance along the polar front.

What atmospheric condition helps a mid‑latitude cyclone intensify?

Upper‑level divergence that removes air above the surface low.

Why do strong temperature contrasts strengthen mid‑latitude cyclones?

They increase instability and available energy for storm development.

What are common regions of mid‑latitude cyclone formation in North America?

Alberta, Colorado, Gulf Coast, and the Atlantic Coast.

What is an Alberta Clipper?

A fast‑moving winter cyclone that forms in western Canada.

What is a Colorado Low?

A mid‑latitude cyclone that forms east of the Rocky Mountains and often intensifies.

What is a Nor’easter?

A strong coastal cyclone along the Atlantic Coast that produces heavy snow, wind, and coastal flooding.

What is the vertical structure of a mature mid‑latitude cyclone?

A surface low with an upper‑level trough that tilts westward with height.

What is the Polar Front Theory?

A theory explaining how cyclones form along the boundary between warm and cold air masses.

What are the stages of the polar front cyclone life cycle?

Wave formation → open wave → mature cyclone → occlusion → dissipation.

What does upper‑level divergence do to surface pressure?

It causes surface pressure to fall, strengthening the cyclone.

What is positive vorticity advection?

The transport of spin into an area that enhances rising motion and cyclone development.

What defines a thunderstorm?

A storm that produces lightning and thunder and contains a cumulonimbus cloud.

What three ingredients are required for thunderstorm formation?

Moisture, atmospheric instability, and a lifting mechanism.

What is a common lifting mechanism for thunderstorms?

Fronts, surface heating, or terrain.

What is an ordinary (single‑cell) thunderstorm?

A short‑lived storm with one updraft and downdraft.

Why do ordinary thunderstorms dissipate quickly?

The downdraft cuts off the warm air supply to the updraft.

What is a multicell thunderstorm?

A group of storms in different life stages that share outflow boundaries.

How do outflow boundaries form new thunderstorms?

Cool air spreading outward lifts warm, moist air ahead of it.

What weather hazards are common with multicell thunderstorms?

Heavy rain, strong winds, and hail.

What is a supercell thunderstorm?

A long‑lived storm with a rotating updraft called a mesocyclone.

Why are supercells especially dangerous?

They can produce large hail, damaging winds, and tornadoes.

How many thunderstorms occur worldwide each day?

About 50,000.

Where are thunderstorms most frequent in the U.S.?

The Southeast and the Great Plains.

What is lightning?

An electrical discharge produced within a thunderstorm.

What causes thunder?

Rapid expansion of air heated by lightning.

What is a tornado?

A violently rotating column of air in contact with the ground and a cloud base.

What is the basic structure of a tornado?

A narrow funnel with the strongest winds near the surface.

In which direction do tornadoes rotate in the Northern Hemisphere?

Counterclockwise.

What is a tornado outbreak?

Multiple tornadoes produced by the same weather system.

When is tornado season most active in the U.S.?

Spring through early summer.

Where do most U.S. tornadoes occur?

Tornado Alley in the central United States.

On which side of a tornado path are winds strongest in the NH?

The left side relative to the direction of motion.

What is the Fujita (EF) Scale?

A scale that rates tornado intensity based on damage (EF0–EF5).

What basic conditions are needed for tornado formation?

Instability, strong vertical wind shear, and lifting.

What type of thunderstorm produces most strong tornadoes?

Supercell thunderstorms.

What is a landspout?

A non‑supercell tornado that forms from surface rotation.

What is a gustnado?

A short‑lived tornado‑like vortex along a gust front.

What is a hurricane?

A tropical cyclone with sustained winds of at least 74 mph.

What are the main structural features of a hurricane?

Eye, eyewall, and spiral rainbands.

What occurs in the eye of a hurricane?

Calm conditions and sinking air.

Where are hurricane winds strongest?

In the eyewall.

Where do hurricanes form?

Over warm tropical oceans.

What ocean temperature is required for hurricane formation?

At least 26.5°C (80°F).

Why does low wind shear matter for hurricanes?

High wind shear disrupts storm organization.

What are the stages of hurricane development?

Tropical disturbance → tropical depression → tropical storm → hurricane.

How are tropical storms named?

From predetermined lists that rotate every six years.

What is the deadliest hurricane hazard?

Storm surge.

Why are winds stronger on one side of a moving hurricane?

Storm motion adds to rotational wind speed.

What is air pollution?

The presence of harmful substances in the atmosphere.

What are natural sources of air pollution?

Volcanoes, wildfires, and dust.

What are anthropogenic sources of air pollution?

Vehicles, factories, and power plants.

What is a primary pollutant?

A pollutant emitted directly into the air.

What is a secondary pollutant?

A pollutant formed through chemical reactions in the atmosphere.

What is an example of a secondary pollutant?

Ozone.

What is the difference between fixed and mobile sources?

Fixed sources are stationary (factories); mobile sources move (vehicles).

Why is tropospheric ozone harmful?

It irritates lungs and damages vegetation.

Why is stratospheric ozone beneficial?

It absorbs harmful ultraviolet radiation.

What trend has occurred in U.S. air pollution since the 1970s?

Overall emissions have decreased.

What is the Air Quality Index (AQI)?

A scale that reports how clean or polluted the air is.

How does wind affect air pollution?

Wind disperses pollutants.

What is a temperature inversion?

A layer of warm air trapping cooler polluted air near the surface.

Why does topography worsen air pollution in valleys?

Pollutants become trapped with limited air circulation.

What is acid deposition?

Acidic precipitation caused by sulfur and nitrogen compounds.

What is particulate matter (PM)?

Tiny solid particles or liquid droplets suspended in the air.

What is an aerosol?

A suspension of fine solid particles or liquid droplets in air.

What is PM10?

Particulate matter with diameters ≤ 10 micrometers that can enter the respiratory system.

What is PM2.5?

Fine particulate matter ≤ 2.5 micrometers that can penetrate deep into the lungs.

Why is PM2.5 more dangerous than PM10?

It reaches deep lung tissue and increases the risk of cardiovascular and respiratory disease.

How is particulate matter removed from the atmosphere?

By wet deposition (precipitation), dry deposition (gravity), and coagulation.

How does PM affect visibility?

It scatters and absorbs light, reducing visual range.

How does particulate matter affect human health?

It increases respiratory illness, heart disease, and mortality risk.

What can be done to reduce PM pollution?

Reduce emissions, improve regulations, and study PM behavior in the atmosphere.

What is weather forecasting?

The process of predicting future atmospheric conditions.

What is the first step in weather forecasting?

Collecting observations from surface stations, satellites, radar, and weather balloons.

What is advection in weather forecasting?

The horizontal movement of air that transports weather conditions.

What are numerical weather prediction models?

Computer models that simulate atmospheric behavior using equations.

Why does forecast accuracy decrease with time?

Small initial errors grow due to atmospheric chaos.

What is Doppler radar?

Radar that measures precipitation and wind motion within storms.

What does Doppler radar detect besides precipitation?

Wind speed and direction within storms.

Why do weather forecasts sometimes go wrong?

Incomplete data, model limitations, and chaotic atmospheric behavior.

What are the main types of weather forecasts?

Short-range, medium-range, and long-range forecasts.

What is global climate?

The long-term average pattern of weather across Earth.

What are the main controls of climate?

Latitude, altitude, land–water distribution, ocean currents, and topography.

How does latitude affect global temperature?

Lower latitudes receive more direct sunlight and are warmer.

What controls global precipitation patterns?

Atmospheric circulation, proximity to oceans, and topography.

What is the Köppen climate classification system?

A system that categorizes climates based on temperature and precipitation.

What characterizes tropical moist climates (Group A)?

Warm temperatures year-round and abundant precipitation.

What defines dry climates (Group B)?

Evaporation exceeds precipitation.

What defines polar climates (Group E)?

Extremely cold temperatures with little precipitation.

What is a highland climate?

A climate controlled mainly by elevation rather than latitude.

How do scientists study past climate changes?

Using ice cores, tree rings, sediment records, and historical data.

What is a climate proxy?

An indirect record used to infer past climate conditions.

What are feedback mechanisms in climate change?

Processes that amplify or reduce climate changes.

What is the ice–albedo feedback?

Melting ice reduces reflectivity, causing further warming.

What are external causes of climate change?

Changes in Earth’s orbit, solar output, and volcanic activity.

How do aerosols affect climate?

They reflect sunlight and cool the atmosphere.