Natural Hazards Overview

Natural Hazards

• Study of natural hazards is crucial due to significant property damage, injury, and death. Economic losses are substantial and difficult to predict.
• Examples used in study include the 1995 Kobe Japan earthquake, Kerala landslides, and Japan earthquake.
• Survivor accounts, expert analyses, and case studies are vital tools.
  • Kerala landslides highlighted hilly areas in southern India's vulnerability during monsoon season.
  • The Japan earthquake showed the importance of building quality and soil conditions.
• Hurricane Helene, a category 4 hurricane, caused significant damage in Florida, Cuba, and Mexico. Factors like high sea surface temperatures, high humidity, and slow movement contributed to severity.
• Hurricane Milton, initially a category 5, later a category 3, caused damage to the West Coast of Florida.
• Super Typhoon Yagi, a powerful storm in Southeast Asia and China, caused significant fatalities and damage.
• Columbia droughts, India heatwaves, Chile wildfires, and Brazil floods highlight recent severe weather events.
• Natural hazards in Canada include earthquakes, icebergs, sea ice, tsunamis, storm surges, floods, landslides, snow avalanches, and volcanic eruptions.
  • In terms of cost for Canada: significant amounts of funds are spent to recover from natural disasters.
• Natural vs. Anthropogenic Hazards: Natural hazards are events where humans have no direct influence (earthquakes, volcanic eruptions); anthropogenic hazards are those where human activity plays a key role (climate change impacting severe weather).
  • Climate change is exacerbating the severity and frequency of many natural hazards.
  • The combined influences of natural and human causes are common in the development of hazards.

Disaster Financial Assistance Arrangements (DFAA)

• DFAA is Canada's system for providing financial aid after a natural disaster.
• Program started in 1970 and has been critiqued by some as needing revision. A major issue is the growing problem of equity in assistance payments.
• The aid is intended to help provinces and territories with recovery but challenges include delays in payout, and inconsistencies in funding depending on factors like the province and the type of disaster.
• The Canadian DFAA has faced considerable pressures due to more frequent and costly natural disasters, often exacerbated by climate change impacts, and a lack of a definitive study on the economic effects of disasters.

A Smart Hazard Approach

• Recognizing hazards specific to an area is essential, but a holistic approach encompassing various hazards is important.
• Globalization and interconnected human activities make hazard impacts regional, and sometimes global.
• To better understand hazards, you need a broader view of how the various parts of the earth interact, and understand the impacts.

Cause vs. Trigger

• Identifying causes and triggers is a critical study because it explains how hazards develop and respond to certain external pressures or conditions.
• Causes represent long-term conditions, setting the stage for the hazard.
• Triggers are short-term events that initiate the hazard's destructive process.
• Hazards can have both natural and human causes.

Hazard vs Risk

• Hazard is the potential for harm.
• Risk is the likelihood of that harm occurring.
• Risk is different from uncertainty, because uncertainty involves circumstances where the outcome and probability of occurrence are not known. Risk differs from risk because it has known probability.
• Risk is independent of vulnerability. Vulnerability is a characteristic of the impacted system.

Magnitude vs. Frequency

• Magnitude is the amount of energy released during a hazard.
• Frequency is the rate at which similar events occur. 
• A high frequency typically indicates a low magnitude.
• Understanding magnitude–frequency relationships is important for assessing hazard risks.

Climate Forcing

• Climate forcing refers to alterations in climate that trigger hazardous responses.
• Variations in Earth's position relative to the sun drive climate change through cycles.
• Climate change is measured by direct (instrumental) records, and indirect (proxy records) of ancient change.
• Proxies can include written historical records, changes in animal bones and plant fossils, and ice cores.

Seasonal Hazards

• Hazards vary seasonally, spatially, and latitudinally.