Fire Science Overview

Fire Science

• Fire requires three components: fuel, oxygen, and heat.
• Preignition involves heating fuel, causing water loss and readiness for ignition.
• Wildfires are becoming more disastrous because of increased fuel availability from past suppression techniques, drier climates (rising global temperatures), and more people living in fire-prone areas.
• Canada's boreal forest is the most fire-prone area.
• A fire is considered extinct when combustion stops, including smoldering.
• Wind heavily influences wildfire spread, intensity, and form.
• Most Canadian wildfires are started by humans.
• Ignition is the point where combustion begins.
• Charcoal is a geological sign of past wildfires.
• Factors affecting earthquake shaking include the distance from the focus, magnitude, and local geology.
• Hot fires can create a water-repellent layer in the soil, increasing the risk of landslides.
• Wildfire behavior is classified based on the fuel layer that allows spreading.
• Lightning is the most important condition for large wildfires over decades to centuries.
• Flaming combustion quickly consumes fuel, while smoldering combustion leaves unburned material.
• A fire regime describes the pattern of fire activity in an area.
• Wildfires release carbon dioxide, water vapor, heat, and light.
• Warmer, drier climates likely contributed to increased wildfires at the end of the Pleistocene epoch.
• Prolonged droughts and excessive fuel buildup were key factors in the severity of the 2003 and 2009 British Columbia fires.
• The natural burn policy in Yellowstone National Park revitalized park ecosystems.

Coastal Processes and Hazards

• Beaches on tectonically passive margins often have extensive sandy beaches.
• Wave fetch, duration, and wind velocity affect wave size.
• East Coast beaches in North America are generally wider and sandier than West Coast beaches due to their distance from convergent plate boundaries.
• Wave size is not influenced by water temperature.
• Hurricanes are named sequentially from a list of names for that year.
• Wave erosion is limited in the Arctic due to limited fetch due to sea ice.
• Hurricanes are a significant threat to the Atlantic coast of Canada.
• Winds around a low-pressure system in the Northern Hemisphere blow counter-clockwise.
• The worst hurricane to hit the East Coast of Canada since 1873 was Hurricane Hazel (1954), followed by Hurricane Juan (2003).
• Wave height is measured by the vertical distance from the wave trough to the crest.
• Forecasts for hurricanes use doppler radar, aircraft, weather satellites, and buoys.
• Littoral drift includes beach drift and longshore drift.
• Waves feel bottom when the water depth is half the wavelength.
• A tropical depression develops into a tropical storm when it develops a distinct central low-pressure zone.
• Barrier island formation requires littoral drift and wave refraction.
• Flying debris causes the most fatalities in hurricanes.
• The Saffir-Simpson scale classifies hurricanes based on wind speed.
• Hurricane risk in the US is increasing due to rising coastal population density.
• The Atlantic hurricane season is typically from June to November.
• Wave erosion is limited in the Arctic due to limited fetch due to sea ice.
• Waves break when they reach shallow water and their height rises.
• Wave period is measured by time between crests.
• Human activity like leveling dunes increases coastal vulnerability to erosion.
• Storm surge is not affected by the age of the storm.
• A hurricane is named when winds reach 63 km/hr.
• Most precipitation in a hurricane occurs in the eye wall.
• A Nor'easter is an extratropical cyclone.
• Storm surges are most influenced by the shape of the coastline.
• Steep rock shorelines are common along the British Columbia coast.
• Hurricane Hazel, an extratropical cyclone, caused 81 fatalities in Toronto.
• Breakwaters are hard stabilizations built to protect harbors.
• Bluff erosion in the Great Lakes is most severe when lake levels are high.
• The Pineapple Express is a flow of warm air that fuels winter extratropical cyclones in the Pacific.
• Hurricanes are least likely to occur in the Southeast Atlantic.
• Storm surge is a large increase in sea level by the action of a storm.
• A typhoon is a hurricane in the Western Pacific Ocean.
• Wave size is not influenced by water temperature.
• Hurricane forward speed is typically less than 27 km/hour.
• Sudden changes in shorelines on the west coast of Canada may be caused by earthquakes.
• Hurricanes are uncommon at the equator because of the lack of the Coriolis Effect.
• Plunging breakers occur when a wave encounters a steep beach.
• Hurricane Juan was a category 2 hurricane.
• Florida has the highest risk of hurricane strikes.
• Extratropical cyclones create strong winter storms.
• Glacio-isostatic subsidence may cause the disappearance of islands.
• The Saffir-Simpson scale ranks hurricanes by wind speed.
• Wave size increases with fetch, and duration of wind.
• Cyclones are characterized by intensity—measured by wind speed and atmospheric pressure.
• A hurricane warning means imminent evacuation for low-lying areas.
• Tropical cyclone development follows: disturbance, depression, storm, hurricane.
• Strong temperature gradients are needed for hurricane formation.
• The lowest risk of hurricanes is in British Columbia.
• Storm surges are rapid local rises in sea level.
• Rainbands are spiraling clouds around a hurricane.
• Tropical storms differ from depressions based on wind speed.
• Water depth significantly influences wave movement. A wave's period, height, and wavelength all influence wave movement, which is not affected by water temperature.
• Coastal erosion from cyclones negatively affects the environment by removing/eroding vegetation, sand, and structures along the coast.
• A tropical depression differs from a tropical disturbance with the presence of a distinct central low-pressure zone.
• Coastal flooding is a result of subsidence.
• Sinkholes are usually formed most likely during times when ground water levels are low.
• Normal fault earthquakes typically occur at divergent plate boundaries.
• Factors that cause land subsidence do not include the creation of frozen ground.
• Reconstruction of communities is usually not considered a proactive response to hazards.

Soil Science

• Expansive soils are characterized by clay minerals.
• Collapse sinkholes result from surface rock and soil falling into underground caves, whereas solutional sinkholes form by dissolution from bedrock surfaces.
• Geologists study earthquake waves to learn about the Earth's interior.
• The hydrologic cycle is driven by solar energy.
• Landfill sinkholes can cause pollutants to seep into groundwater.
• Soil originates from weathered rock.
• Soil grain sizes (smallest to largest): clay, silt, sand, gravel.
• Karst topography is characterized by sinkholes and underground caves.
• Subsidence is the sinking of the ground surface.
• Coastal flooding is sometimes a result of land subsidence.
• Sinkhole collapse is more likely when groundwater levels are low.