Environmental Management (0680) | Managing the impacts of natural hazards

Environmental Management (0680) Study Notes: Managing the Impacts of Natural Hazards

Hello future Environmental Manager! This chapter is all about how we cope when Mother Nature throws a big challenge our way, like earthquakes, cyclones, floods, or droughts. Understanding how these hazards hurt people and the environment, and what we can do to prepare, is key to saving lives and building resilient communities. Let’s dive into managing these impacts!

SECTION 6.5: The Impacts of Natural Hazards

Natural hazards can cause widespread damage, affecting the environment, the economy, and human society. It's important to be able to describe the specific impacts of different types of hazards.

I. Impacts of Tectonic Events (Earthquakes, Volcanoes, Tsunamis)

These events happen suddenly and are often devastating because we cannot easily predict the exact time they will strike.

• Physical Damage: Severe damage to buildings and infrastructure (roads, bridges, hospitals, power lines).
• Secondary Hazards: Earthquakes can trigger *fire* (due to broken gas lines), *landslides*, and *tsunamis*.
• Environmental Loss: Loss of farmland and habitats due to landslides or volcanic ash coverage.
• Human Cost: Massive loss of life and severe *trauma* (psychological distress).
• Health Issues: Water-related diseases (e.g., cholera) spread rapidly if water supplies are contaminated by ruptured sewage pipes.
• Economic Cost: Huge financial losses due to destroyed property and disruption of businesses.

II. Impacts of Tropical Cyclones and Flooding

While often linked, floods can happen independently of cyclones (e.g., due to heavy rain or snowmelt). Both involve large amounts of water and subsequent destruction.

Impacts of Cyclones and Flooding include:

• Immediate Loss: Rapid loss of life (drowning) and loss of livestock.
• Crop Destruction: Loss of crops—fields are either washed away or ruined by saltwater inundation (in coastal areas).
• Infrastructure Damage: Significant damage to buildings and transport infrastructure from high winds and rushing water.
• Contamination: Contamination of drinking water supplies (as floodwaters mix with sewage).
• Disease: Increased risk of water-related disease (like typhoid or cholera).
• Habitat Loss: Destruction of coastal habitats like mangrove forests and coral reefs.

III. Impacts of Drought

Drought is a prolonged period of abnormally low rainfall, causing severe water shortages. The impacts are slower but can last longer.

• Ecosystem Collapse: Death of plants and animals (death of organisms).
• Water Scarcity: Rivers, reservoirs, and wells (water sources dry up).
• Food Crisis: Significant decline in crop yields, leading to starvation and malnutrition.
• Land Degradation: Increased soil erosion because dry soil is easily blown away by wind, potentially leading to desertification (the land becoming desert-like).
• Air Quality: Decrease in air quality due to dust storms.
• Wildfires: Increased risk of wildfires due to extremely dry vegetation.

SECTION 6.6: Managing the Impacts of Natural Hazards

The best way to deal with natural hazards is to use a Management Cycle, which involves steps taken Before (Mitigation), During (Response), and After (Recovery/Rebuilding) the event. We need different strategies for different hazards.

I. Managing Tectonic Events (Earthquakes and Volcanoes)

A. Before the Event (Mitigation & Preparation):

• Monitoring and Warning: While predicting earthquakes is hard, monitoring volcanic activity (seismic activity, gas emissions) helps.
• Land Use Zoning: Preventing the construction of critical facilities (like hospitals or power stations) in high-risk zones, especially near fault lines or active volcanoes.
• Structure of Buildings: Constructing buildings to withstand shaking (e.g., using flexible materials, steel frames, deep foundations, or shock absorbers).
• Disaster Preparation: Creating emergency plans, running drills, storing emergency supplies (water, food, first aid kits), and training emergency rescue teams.

B. During and After the Event (Response & Recovery):

• Evacuation: Moving people away from immediate danger zones (crucial for tsunamis and volcanic eruptions).
• Rebuilding: When structures are rebuilt, strict building codes must be enforced to ensure they are safer next time.
• International Aid: Providing funds, medical supplies, and trained personnel from other countries (NGOs and governments).

II. Managing Tropical Cyclones and Flooding

A. Cyclones:

• Monitoring and Warning: Using satellites and weather stations to track the storm's path and wind speed, allowing for several days of warning.
• Structure of Buildings: Strengthening buildings, especially roofs and windows, to withstand high winds.
• Evacuation: Issuing mandatory evacuation orders for low-lying or coastal areas, directing people to *emergency shelters*.
• Disaster Preparation: Taping windows, securing outdoor objects, having emergency kits ready.

B. Flooding:

• Monitoring: Using storm hydrographs to monitor river levels. If levels rise too quickly, warnings are issued.
• Hard Engineering Flood Management Techniques: Building *dams* (to hold back water), *levees* (high river banks), and *flood barriers*.
• Soft Engineering Flood Management Techniques: Using natural methods like maintaining vegetation cover, creating *washlands* (areas deliberately flooded to protect urban areas), and dredging rivers.
• Response: Rescue operations and providing safe, temporary *shelters*.

III. Managing Drought

Managing drought focuses heavily on long-term planning related to water supply and conservation.

A. Monitoring and Conservation:

• Monitoring: Tracking rainfall levels and soil moisture over long periods.
• Water Conservation: Educating the public and farmers about efficient water use. Strategies include using trickle drip irrigation instead of sprinklers, fixing leaks, and reducing domestic water usage.

B. Increasing Water Supply:

• Dams and Reservoirs: Building large storage facilities, although these can have major environmental impacts.
• Wells and Aquifers: Pumping groundwater from natural underground rock layers (*aquifers*).
• Water Transfer Schemes: Moving water from water-rich regions to water-poor regions (like pipelines or canals).
• Desalination: Removing salt from seawater to make it potable (drinkable). This is expensive and energy-intensive.
• Rainwater Harvesting: Collecting and storing rainwater, especially in rural areas.

C. Response: Providing emergency water supplies and requesting international aid for food and funds.

IV. Comparison: MEDCs vs. LEDCs Case Studies

When studying how countries manage tectonic events (or any hazard), you must compare More Economically Developed Countries (MEDCs) and Less Economically Developed Countries (LEDCs).

	MEDCs (e.g., Japan, USA)	LEDCs (e.g., Haiti, Pakistan)
Prevention & Mitigation (Before)	High investment in *monitoring technology*, strict *land use zoning*, and *advanced building structures*. Focus on reducing the hazard's impact before it strikes.	Low investment due to cost. Less effective building codes. Monitoring equipment is often lacking or poorly maintained.
Response (During)	Highly trained emergency services, quick coordination, well-rehearsed evacuation drills, established emergency supply networks.	Slower response, poor infrastructure makes rescue difficult, and reliance on international help for immediate relief.
Recovery (After)	Governments have the wealth to finance rapid rebuilding and provide quick financial support to affected citizens.	Recovery is very slow; often dependent on long-term *international aid* which can take time to arrive and distribute.

SECTION 6.7: Opportunities Presented by Natural Hazards

It sounds strange, but natural hazards can sometimes create positive opportunities!

I. Opportunities from Volcanic Activity

• Fertile Soils: Volcanic ash, over time, breaks down into nutrient-rich soil called *alluvium*. This makes the land around volcanoes incredibly productive for agriculture.
• Extraction of Minerals: Volcanoes bring valuable *minerals* (like sulfur, copper, gold) closer to the Earth’s surface where they can be mined.
• Geothermal Energy Resources: Heat from underground magma can be used to generate clean electricity (steam turns turbines). Iceland is a great example of a country that relies heavily on geothermal power.

II. Opportunities from Flooding

• Deposition of Silt on Farmland: When rivers flood their banks, they deposit fine, nutrient-rich sediment (*silt*) onto the adjacent farmland. This natural fertilisation greatly improves soil quality and increases crop yields (historically crucial in river valleys like the Nile).