Natural Hazards
What is a natural hazard? Give one example.
A natural hazard is a natural event that can cause harm to people or property. An example is an earthquake.
What makes a natural hazard become a natural disaster?
A natural hazard becomes a disaster when it causes major damage, injuries, or loss of life.
What instrument do scientists use to detect earthquakes?
A seismograph.
Give one way cities can reduce damage from hurricanes.
Cities can build seawalls to reduce flooding from storm surge.
You hear a tornado siren while you are outside. What is the safest action you should take immediately?
Get to a sturdy building and move to a basement or an interior room away from windows.
Name two weather-related natural hazards.
Hurricanes and tornadoes.
Give one example of a natural disaster caused by a hurricane.
Hurricane Katrina caused massive flooding in New Orleans when storm surge broke levees (engineered earthen or concrete ridges built alongside rivers, coasts, or canals to control water flow and protect adjacent lands from flooding )
Name two tools scientists use to track hurricanes.
Satellites and weather radar.
Name two strategies to reduce earthquake damage.
Using earthquake-resistant building designs and practicing emergency drills.
A hurricane is predicted to hit your town in 3 days. Name one thing your family should do to prepare.
Stock up on supplies, secure outdoor items, or make an evacuation plan.
Describe how a volcano becomes a hazard (use the words magma and lava).
A volcano becomes a hazard when magma rises toward the surface and erupts as lava, releasing ash, gases, and hot rock.
Describe how a volcanic eruption could bury a city quickly.
Ash fall, lava flows, and pyroclastic flows can rapidly cover buildings and roads, burying a city.
Explain how wind direction and lava-flow maps help prediction near volcanoes.
Wind direction helps predict where ash will fall, and lava-flow maps show where lava is likely to travel, helping people choose safer locations.
Explain what an evacuation route and hazard map are and how they help.
An evacuation route shows safe ways to leave an area, and a hazard map shows dangerous zones so people know where it is safe to live or travel.
Scientists warn that a volcano near a town may erupt soon. Why is it safer to evacuate early rather than wait?
Evacuating early helps people avoid ash, lava, and fast-moving flows that can happen suddenly.
Explain why topography (land shape) affects the direction lava or mudflows travel.
Lava and mudflows move downhill, so the shape and slope of the land control where they flow.
Explain why some earthquakes cause tsunamis and others do not.
Only earthquakes that move the ocean floor suddenly can push water and create a tsunami.
Describe one human activity that can increase sinkholes and why.
Pumping too much groundwater removes support underground, causing the land to collapse.
Design a three-step emergency plan for Tornado Alley.
Watch for weather warnings, go to a basement or interior room, and have an emergency kit ready.
After heavy rain, cracks appear in the ground near homes. What hazard might this signal, and why should people be careful?
t could signal a sinkhole, which can collapse suddenly and damage homes or roads.
Compare and contrast a sudden hazard and a slow-developing hazard, including detection.
An earthquake happens suddenly with little warning and is detected using seismographs. A drought develops slowly over time and is detected by measuring rainfall, soil moisture, and water levels.
Compare a VEI 1 and VEI 6 eruption.
A VEI 1 eruption is small with little ash and limited damage nearby. A VEI 6 eruption is very explosive, sends ash high into the atmosphere, and can affect large regions and climate.
Propose a monitoring plan for a coastal city near a fault line and river.
Scientists should monitor river water levels, rainfall amounts, ground shaking with seismographs, and land movement to assess flood and earthquake risks.
Evaluate seawalls, alerts, and buyouts for hurricane risk.
Seawalls protect against flooding but are expensive. Emergency alerts save lives but do not stop damage. Buyouts reduce long-term risk but require people to relocate.
A community keeps rebuilding in a floodplain after repeated floods. What long-term solution could reduce risk, and why?
Relocating buildings or restoring wetlands can reduce future flood damage by keeping people out of high-risk areas.