Natural Hazard Midterm

  1. What is a natural hazard?
    A natural hazard is a dangerous natural event like a flood, earthquake, or storm that can cause harm to people, property, or the environment.

  2. List the seven main areas of human security.

    Economic

    Food

    Health

    Environmental

    Personal

    Community

    Political

  3. What is the difference between natural hazards and human-made (technological) hazards?
    Natural hazards come from nature (like hurricanes), while human-made hazards are caused by people (like oil spills or nuclear accidents).

  4. Name and briefly describe the four main types of natural hazards:

  • Atmospheric: Related to weather (e.g. hurricanes, tornadoes)

  • Hydrological: Related to water (e.g. floods, tsunamis)

  • Lithospheric: Related to Earth's crust (e.g. earthquakes, volcanoes)

  • Biospheric: Related to living organisms (e.g. diseases, locust swarms)

  1. How can natural hazards impact society, economy, and the environment?
    They can destroy homes and infrastructure, hurt economies, cause deaths, and damage ecosystems.

  2. Why is it important to study and understand natural hazards?
    So we can predict them, reduce damage, save lives, and improve emergency responses.

  3. What is the connection between natural hazards and sustainability?
    Understanding hazards helps us build safer, more resilient communities and use resources wisely, which supports sustainability.

  4. How can governments and societies prepare for natural hazards?
    By making emergency plans, building strong infrastructure, educating people, and monitoring risks.

  5. Describe one recent natural disaster and explain its main effects.
    (Example) In 2023, wildfires in Canada burned millions of acres, forced evacuations, caused poor air quality, and affected global weather patterns.

  6. Explain the process of fusion in stars.
    Fusion is when hydrogen atoms join together under high pressure and temperature to form helium, releasing huge amounts of energy — it’s how stars shine.

  7. What is the Chandrasekhar limit?
    It’s the maximum mass (about 1.4 times the Sun’s) a white dwarf star can have before collapsing into a neutron star or black hole.

  8. Why is the synthesis of iron in a star and the formation of a supernova significant?
    When a star makes iron, it can't produce more energy through fusion. The core collapses, causing a massive explosion called a supernova, spreading elements into space.

  9. How was the Solar System formed?
    From a cloud of gas and dust called a solar nebula. Gravity pulled it together, forming the Sun in the center and planets from the leftover material.

  10. Explain the Kardashev scale of measuring civilizational technological advancement.
    It measures how advanced a civilization is based on its energy use:

  • Type I: Uses all energy on its planet

  • Type II: Uses energy of its star

  • Type III: Uses energy of its whole galaxy

  1. Explain the solar cycle.
    A repeating 11-year cycle where the Sun’s activity rises and falls — including sunspots, flares, and solar storms.

  2. What are sunspots?
    Dark, cooler spots on the Sun caused by strong magnetic fields. They’re linked to solar activity.

  3. Explain solar storms.
    Bursts of energy from the Sun, including solar flares and CMEs, which can affect satellites, power grids, and radio communication.

  4. What is a coronal mass ejection (CME)?
    A massive burst of solar plasma and magnetic field released into space — it can cause geomagnetic storms on Earth.

  5. What is a solar hazard?
    Any solar activity, like flares or CMEs, that can disrupt satellites, electronics, or power systems on Earth.

  6. Explain ozone and ozone holes, and their connection with UV radiation.
    Ozone is a gas in the atmosphere that blocks harmful UV rays. Ozone holes are areas with less ozone, letting more UV reach Earth, increasing health risks.

  7. What is a gamma-ray burst, and what consequences would it have on the atmosphere?
    A super-powerful burst of gamma rays from space. If one hit Earth, it could destroy the ozone layer and harm life.

  8. Briefly explain black holes.
    Black holes are collapsed stars with gravity so strong that nothing, not even light, can escape from them.

  9. What is the impact of a celestial body?
    It’s when an object like an asteroid or comet crashes into a planet — it can cause explosions, craters, or even global disasters.

  10. What are asteroids and what are they made of?
    Asteroids are rocky objects that orbit the Sun, mostly made of rock, metal, or a mix of both.

  11. What are the main groups of asteroids?

  • Main belt asteroids (between Mars and Jupiter)

  • Trojans (share orbit with a planet)

  • Near-Earth asteroids (come close to Earth)

  1. Where is the main asteroid belt located?
    Between Mars and Jupiter.

  2. What are comets and what gives them their tail?
    Comets are icy bodies. When they get near the Sun, the heat causes the ice to vaporize and form a glowing tail.

  3. What is a coma in a comet, and what types exist?
    The coma is the fuzzy cloud around a comet’s nucleus. It has two parts:

  • Gas coma (from evaporated gases)

  • Dust coma (from dust particles)

  1. What is the Oort Cloud and what is its role?
    A distant, spherical cloud of icy objects around the Solar System — it's where long-period comets come from.

  2. What is the difference between asteroids, comets, and meteors?

  • Asteroids: rocky, no tail

  • Comets: icy, have tails

  • Meteors: streaks of light when space rocks burn in Earth’s atmosphere

  1. What are meteoroids, meteors, and meteorites?

  • Meteoroid: small space rock

  • Meteor: when it enters and burns in Earth’s atmosphere

  • Meteorite: what’s left if it hits the ground

  1. What happened during the Tunguska explosion in 1908?
    A space object exploded over Siberia, flattening 2,000 km² of forest — it’s the biggest impact event in recent history.

  2. What happened in Chelyabinsk in 2013 and what were the consequences?
    A meteor exploded over Russia. It injured about 1,500 people (mostly from broken glass) and damaged buildings.

  3. What could happen if a large asteroid hit Earth?
    It could cause fires, tsunamis, climate change, or even mass extinction, like what happened to the dinosaurs.

  4. What is the probability of a globally catastrophic impact?
    Very low in the short term, but it’s possible over millions of years — that’s why scientists monitor space objects.

  5. How do scientists detect and track near-Earth objects (NEOs)?
    Using telescopes, radar, and space missions to observe, calculate orbits, and predict possible impacts.

  6. What can we do to stop or deflect a dangerous asteroid?
    Use space missions to push it off course, like NASA’s DART mission, or explore options like nuclear devices or gravity tractors.