Environmental Science Natural Disasters and Environmental Hazards 1 — Questions and Answers
Question 1: Which type of natural hazard is primarily caused by the movement of tectonic plates along fault lines?
- Hurricanes
- Earthquakes (Correct answer)
- Wildfires
- Droughts
Correct answer: Earthquakes
Earthquakes are caused by the sudden release of energy as tectonic plates slip or fracture along fault lines.
Question 2: The Richter scale is used to measure which characteristic of an earthquake?
- Depth of the epicenter
- Duration of shaking
- Magnitude (energy released) (Correct answer)
- Geographic extent of damage
Correct answer: Magnitude (energy released)
The Richter scale quantifies the magnitude, or total energy released, by an earthquake using seismograph readings.
Question 3: Which atmospheric condition is the primary driver for the formation of a hurricane?
- Cold ocean surface temperatures below 60°F
- Warm ocean surface temperatures above 79°F (26°C) (Correct answer)
- High-pressure systems over land
- Strong upper-level wind shear
Correct answer: Warm ocean surface temperatures above 79°F (26°C)
Hurricanes require warm ocean surface water (at least 26°C/79°F) to provide the heat and moisture energy that fuels their development.
Question 4: A tsunami is most commonly triggered by which event?
- A Category 5 hurricane making landfall
- A large submarine earthquake or undersea landslide (Correct answer)
- Rapid coastal erosion during storm surge
- Volcanic ash clouds over the ocean
Correct answer: A large submarine earthquake or undersea landslide
Most tsunamis are generated by large submarine earthquakes that displace the ocean floor, causing a series of powerful waves.
Question 5: What is the term for the geographic zone around a volcano where the most severe pyroclastic hazards are likely to occur?
- Exclusion zone (Correct answer)
- Lahar corridor
- Danger zone
- Primary impact zone
Correct answer: Exclusion zone
An exclusion zone is the designated area around an active volcano where access is restricted due to the high risk of pyroclastic flows, ash fall, and lahars.
Question 6: Which type of flood occurs with little or no warning due to intense, localized rainfall in a short period?
- Riverine flood
- Coastal flood
- Flash flood (Correct answer)
- Ice-jam flood
Correct answer: Flash flood
Flash floods develop rapidly—often within six hours—due to intense rainfall over a small area, leaving little time for warning or evacuation.
Question 7: The 'fire triangle' concept describes the three elements required for a wildfire to ignite and spread. Which set correctly identifies these elements?
- Wind, slope, and fuel
- Heat, fuel, and oxygen (Correct answer)
- Drought, wind, and terrain
- Ignition, humidity, and fuel
Correct answer: Heat, fuel, and oxygen
The fire triangle consists of heat (ignition source), fuel (combustible vegetation or materials), and oxygen, all of which must be present simultaneously for combustion.
Environmental Science Natural Disasters and Environmental Hazards 1
Which type of natural hazard is primarily caused by the movement of tectonic plates along fault lines?