How and why have risks from tectonic hazards changed over time?

Question 1

How and why have risks from tectonic hazards changed over time?

Answer 1

• Natural disasters have increased
• Increase in frequency and magnitude of meteorological and hydrological hazards (explained by human and physical factors)
  EX – deforestation can have direct causative influence on hazardous events ie flooding

Question 2

Meteorological

Answer 2

weather hazards -> increasing due to climate change

Question 3

Hydrological

Answer 3

flooding hazards -> increasing due to climate change

Question 4

Geophysical

Answer 4

volcanic and seismic hazards -> they’re not increasing
BUT we’re recording them more and severity increasing because of increase population and population density = increase disaster when caused

Question 5

Trends in tectonic hazards

Answer 5

• Timescales over which tectonic forces operate are so long that graphs of past earthquake and volcanic events need to be interpreted with care.
• Past 50years have seen increase in no. of disasters -> 30 annually
• Fatalities, numbers affected and economic cost increase in disaster

Question 6

why are more people being effected?

Answer 6

• increased due to population growth and increase in population density
• urbanisation = more infrastructure and advanced technologies
• urbanisation causes landslides in rural areas which are less well equipped
• earthquakes have significantly higher death toll than eruptions.
  EX - Most deadly eruption = Indonesia 322 killed, earthquake in Indonesia killed 222,500
• death tolls may be higher as the hazard itself is more widespread and affects a larger area
• causes other hazards such as tsunamis, landslides and avalanches = area more dangerous.
• Volcanoes eruptions are localised, also advanced mitigation strategies in place – can evacuate an eruption you cannot do this with earthquake