Hazard & Disaster Trends (SL IB Geography)

Global disaster trends

• The number of recorded disasters has increased significantly since 1960
• There are a number of reasons for this, including:
  • Increased population – the world's population has grown from 3 billion to over 8 billion since 1960:
    • This means more people are likely to be impacted by any hazard event
    • Increased population density in urban and coastal areas increases the vulnerable population
  • Increased monitoring and reporting means more hazard events are recorded
• Most of the increase has been the result of floods and extreme weather

Recorded global disasters 1900–2022

Recorded global disasters 1900–2022

Geophysical hazard trends 

• The number of tectonic disasters has fluctuated since 1960 but has generally remained steady
• The slight increase in the number of earthquake disasters does not mean there have been more earthquakes or higher magnitude earthquakes. It results from:
  • Greater urbanisation in seismic zones, which has led to higher population densities and increased building density
  • Population growth, which means more people are living in earthquake-prone regions
  • Population growth being focussed in some of the least developed countries, which are also the most vulnerable due to:
    • Poor building design and construction
    • Poverty
    • Lower levels of education
    • Poor governance

Global tectonic disasters 1900–2022

Global tectonic disasters 1900–2022

• The number of deaths from tectonic hazards fluctuates depending on a range of factors, including:
  • Magnitude
  • Level of development
  • Location

Deaths resulting from tectonic activity

                                                  1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010  2020

Deaths resulting from tectonic activity

• The impact of a mega-disaster such as the Indian Ocean earthquake and tsunami may skew the overall trend because it leads to so many deaths
• Volcanic eruptions are less frequent than earthquakes and deaths from eruptions are now rare due to improved monitoring, exclusion zones and evacuation plans