Impacts on Development: Why Do Natural Disasters Hit Some Places Harder?

Hey everyone! Ever wondered why a big earthquake can cause massive devastation in one country, while a similar-sized one causes much less damage in another? It's not just about luck or the strength of the disaster. It's about development.

In this chapter, we're going to explore the powerful and sometimes tragic relationship between natural hazards and a country's level of development. We'll uncover why poorer areas are often more vulnerable and what can be done to protect people. This is super important because it helps us understand our world and the inequalities within it. Let's get started!


Section 1: The Effects of Tectonic Hazards

First, let's be clear on what we're talking about. Tectonic hazards are natural events caused by the movement of the Earth's plates. For this topic, we focus on three main types:

  • Earthquakes: A sudden, violent shaking of the ground.
  • Volcanic Eruptions: When lava, ash, and gases escape from a volcano.
  • Tsunamis: Giant ocean waves, often caused by underwater earthquakes.

The damage these hazards cause can be split into two types: primary and secondary effects. Don't worry, it's simpler than it sounds!

Primary vs. Secondary Effects: A Simple Guide

Think of it like getting a paper cut. The cut itself is the primary effect. The infection you might get a few days later is the secondary effect.

  • Primary Effects: These happen immediately as a direct result of the hazard. They are the instant damage.
  • Secondary Effects: These happen later on, as a result of the primary effects. They are the knock-on consequences.
Examples of Effects on People and the Environment

Earthquakes

  • Primary Effects: Buildings and bridges collapsing, roads cracking, people being killed or injured by falling objects.
  • Secondary Effects: Fires from broken gas pipes, landslides triggered by the shaking, homelessness, spread of diseases like cholera from contaminated water.

Volcanic Eruptions

  • Primary Effects: Homes and forests destroyed by lava flows, people and animals killed by pyroclastic flows (super-hot clouds of ash and gas), suffocation from volcanic gases.
  • Secondary Effects: Lahars (mudflows) caused by melted snow or rain mixing with ash, air travel disruption from ash clouds, long-term climate change from sulphur dioxide, contaminated water supplies.

Tsunamis

  • Primary Effects: People drowning, buildings smashed by the force of the water, boats washed inland.
  • Secondary Effects: Widespread flooding, agricultural land destroyed by salt water, homelessness, disease from polluted water and dead bodies.
Key Takeaway

Natural hazards cause both immediate (primary) damage and long-term, knock-on (secondary) problems. Understanding both is crucial to see the full impact on a society.


Section 2: Can We Reduce the Impact? Hazard Management Strategies

Yes, we can! While we can't stop an earthquake from happening, we can take steps to reduce its impact. These measures are all about being prepared and making our communities safer. The syllabus groups them into a few key areas.

Monitoring, Predicting and Warning Systems

This is all about using technology to keep an eye on the Earth and give people a heads-up before a disaster strikes.

  • Monitoring: Using scientific equipment to detect signs that a hazard might happen. For example, using seismometers to measure tremors near a volcano, or thermal imaging to detect rising magma.
  • Predicting: Using monitoring data to make an educated guess about when and where a hazard might occur. It's very hard to predict earthquakes accurately, but we are much better at predicting volcanic eruptions and the path of tsunamis.
  • Warning Systems: Getting the message out to the public once a threat is identified. Think of tsunami sirens on a beach or SMS alerts sent to phones. The DART system uses sea-bed sensors and buoys to detect tsunamis in the ocean and warn coastal areas.

Disaster Mitigation and Preparation

These two sound similar, but there's a key difference.

  • Mitigation (Long-term protection): These are actions taken to make the hazard's impact less severe. It's about building long-term safety.
    Examples: Building earthquake-resistant buildings, strengthening existing bridges, avoiding construction in high-risk areas.

  • Preparation (Getting ready for it to happen): These are actions taken just before or during a hazard to respond safely.
    Examples: Creating evacuation plans, holding earthquake drills in schools (like a fire drill!), preparing emergency supply kits with food, water, and first aid.

Land Use Zoning

This is a clever mitigation strategy. It means that governments designate certain areas of land for specific uses based on risk.

Think of it this way: You wouldn't build a hospital on the steep, unstable side of a volcano, or a school right on a fault line. Land use zoning means creating laws that prevent this. Important buildings like hospitals and power plants are built in the safest areas, while high-risk zones might be used for parks or farmland where fewer lives would be at risk.

Key Takeaway

We can reduce a hazard's impact through a combination of technology (monitoring & warning), planning (land use zoning), and preparation (drills & education). However, the effectiveness of these measures often depends on a country's wealth and resources.


Section 3: Why are Less Developed Areas (LDAs) More Vulnerable?

This is the core of our chapter! A huge earthquake hits Japan (a More Developed Area) and Haiti (a Less Developed Area). The death toll in Haiti is thousands of times higher. Why? The answer is vulnerability.

Vulnerability means how susceptible a community is to the damaging effects of a hazard. LDAs are far more vulnerable than MDAs due to a combination of social, economic, and technological factors.

Comparing Vulnerability: LDA vs. MDA

Let's break down the key reasons using a simple mnemonic: P.E.T. G. (Poverty, Education, Technology, Government).

Poverty & Socio-Economic Gaps
  • MDAs: Have more money to spend on hazard management. They can afford early warning systems, strong building materials, and well-equipped rescue teams. Their economies can also recover more quickly after a disaster.
  • LDAs: Lack of money is the biggest problem. They can't afford advanced technology or earthquake-proof buildings. People often live in poorly built, overcrowded housing because it's all they can afford. A disaster can wipe out their entire economy.
Education & Awareness
  • MDAs: Have higher literacy rates and government-funded education campaigns. People are taught what to do in an earthquake from a young age. They know to "drop, cover, and hold on."
  • LDAs: Lower literacy levels and less access to information mean many people may not understand the risks or know how to react. There might not be any formal education on disaster preparedness.
Technological Gaps
  • MDAs: Have access to the best technology for monitoring (satellites, seismometers) and construction (earthquake-proof designs with shock absorbers and reinforced steel).
  • LDAs: Rely on older, less effective technology, or none at all. Buildings are often made from cheap, heavy materials (like concrete blocks) that collapse easily.
Government & Planning
  • MDAs: Usually have stable governments that can create and enforce strict building codes and land use zoning laws. They have official, well-funded disaster response agencies.
  • LDAs: Governments may lack the resources to enforce laws, or suffer from corruption. There may be no official evacuation plans or disaster management teams, leading to a slow and chaotic response.
Quick Review: Why are LDAs more vulnerable?

Poorly constructed buildings + Lack of warning systems + Limited education + Slow government response = A recipe for disaster.

Key Takeaway

The level of damage from a natural hazard is NOT just about its physical strength. It's hugely influenced by the level of development. Poverty creates vulnerability, turning a natural hazard into a human catastrophe.


Section 4: Living with Risk - Why Do People Stay in Hazard-Prone Areas?

You might be thinking, "If it's so dangerous, why don't people just move away?" The answer is complex. For many, the choice to stay is perfectly rational when you consider the advantages of living there and the disadvantages of leaving.

The Advantages (The "PULL" factors)

Hazardous areas can also be places of great opportunity.

  • Economic Advantages:
    • Farming: Volcanic ash creates incredibly fertile soil, which is perfect for agriculture. (e.g., growing coffee on the slopes of volcanoes in Indonesia).
    • Tourism: Spectacular volcanic landscapes, geysers, and hot springs attract millions of tourists, creating jobs. (e.g., Iceland or Japan).
    • Energy: Geothermal heat from volcanic areas can be used to generate clean electricity.
    • Resources: Volcanoes bring valuable minerals like diamonds, gold, and copper closer to the surface.

  • Social & Cultural Reasons:
    • Lack of Choice: This is the biggest reason for people in LDAs. They are often too poor to move. Their entire life—family, job, home—is there. They have nowhere else to go.
    • Place Attachment: People have a strong connection to their home. Their families may have lived there for generations, and they don't want to leave their community and culture behind.
    • Perception of Risk: Some people may not be aware of the true level of risk, or they believe a disaster is so rare that it won't happen in their lifetime.
Did you know?

The area around the Pacific Ocean, called the "Ring of Fire," has about 75% of the world's volcanoes and 90% of its earthquakes. Yet, hundreds of millions of people live there, including in major cities like Tokyo, Mexico City, and Los Angeles!

Is the Choice Rational?

Yes, it can be. "Rational" doesn't mean "risk-free." It means making a decision where the perceived benefits outweigh the perceived risks.

  • For a farmer in an LDA, the benefit of fertile soil to feed their family outweighs the rare risk of an eruption.
  • For a wealthy city-dweller in an MDA, the benefit of a high-paying job is worth the risk, especially when they live in an earthquake-proof building and trust the government's warning systems.
Key Takeaway

People live in hazardous areas for powerful economic and social reasons. Often, especially in LDAs, it is not a matter of choice but of necessity. Their decision to stay is often a rational calculation based on their unique circumstances.