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Oluwakemi Izomo. Natural and Anthropogenic Hazards: Overview. Natural Hazards. Trends. Hans-Peter Plag September 15, 2014. Distinction between trends and hazardous events. Trends change the hazard spectrum: can cause more frequent, more extreme hazards
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Natural and Anthropogenic Hazards: Overview Natural Hazards Trends Hans-Peter Plag September 15, 2014
Distinction between trends and hazardous events • Trends change the hazard spectrum: • can cause more frequent, more extreme hazards • can lead to new hazards or eliminate old ones
We distinguish four categories of large disasters: Extinction Level Events are so devastating that more than a quarter of all life on Earth is killed and major species extinction takes place. Global Catastrophes are events in which more than a quarter of the world human population dies and that place civilization in serious risk. Global Disasters are global scale events in which a few percent of the population die. Major Disasters are events exceeding $100 Billion in damage and/or causing more than 10,000 fatalities. Modified from Hempsell (2004). Distinction between hazards and disasters Understanding the processes that lead from hazard to disaster
Casti (2012): X-events: rare, surprising events with potentially huge impact on human life. Outliers of the “normal” region; could lead to the collapse of everything.
Hazardous events: disturbances • natural hazards • geohazards (earthquakes, landslides, tsunamis, volcanic eruptions, subsidences) • hydrometeorological hazards (floods, droughts, storm surges, hurricanes, tornadoes) • epidemics and pandemics • wild fires • extraterrestrial objects • anthropogenic hazards • wars and conflicts • terrorist attacks • crime • social unrest • industrial/infrastructure failure • economic crisis
Trends and slow changes • Trends in the environment: • climate change and its consequences • global warming • sea level rise and ocean circulation • ocean chemistry • ecosystem impacts • crossing global boundaries (leaving the Holocene) • biodiversity • Nitrogen cycle • water cycle • land use • diseases and resistance • Trends in the anthroposphere • political changes • economic changes • technological changes and revolutions
Natural hazards • geohazards (earthquakes, landslides, tsunamis, volcanic eruptions, subsidences) • hydrometeorological hazards (floods, droughts, storm surges, hurricanes, tornadoes) • epidemics and pandemics • wild fires • extraterrestrial objects
100,000 40,000 30,000 25,000 15,000 10,000 5,000 4,000 3,500 3,400 1) Krakatau was similar to Santorini eruption, 1600 BC, although 4 times smaller Eyafjallajokull, 2010: VEI 4, 0.25 km3 Laki 1783-85: VEI 6, 14 km3 Volcanic Eruptions Several eruptions that happened during the last 2,000 years would be devastating under todays conditions
Natural hazards • geohazards (earthquakes, landslides, tsunamis, volcanic eruptions, subsidences) • hydrometeorological hazards (floods, droughts, storm surges, hurricanes, tornadoes) • epidemics and pandemics • wild fires • extraterrestrial objects
Natural hazards • geohazards (earthquakes, landslides, tsunamis, volcanic eruptions, subsidences) • hydrometeorological hazards (floods, droughts, storm surges, hurricanes, tornadoes) • epidemics and pandemics • wild fires • extraterrestrial objects • Epidemics and pandemics • “Black death”: 1346-1353 in Europe, 75 to 200 million deaths; 30% to 60% of the population • “Spanish Flue”: 1918-1920, worldwide, 50 to 100 million deaths, 3%-5% of the global population
Anthropogenic hazards • wars and conflicts • terrorist attacks • crime • social unrest • industrial/infrastructure failure • economic crisis
11.1% Genghis Khan
Trends in the anthroposphere • political changes • economic changes • technological changes and revolutions
Trends in the environment: • climate change and its consequences • global warming • sea level rise and ocean circulation • ocean chemistry • ecosystem impacts • crossing global boundaries (leaving the Holocene) • biodiversity • Nitrogen cycle • water cycle • land use • diseases and resistance
The “global boundaries” of the “safe operating space for humanity” (Rockström et al., 2009) We are leaving the Holocene: Climate Change (***) Ocean acidification (**) Stratospheric ozone depletion (*) Nitrogen (******) and Phosphorous cycles (**) Global freshwater (*) Change in land use (*) Biodiversity loss (*******) Atmospheric aerosols (?) Chemical pollution (?) Climate change and sea level rise are symptoms, not the cause, not the “sickness.” We are pushing Earth out off the Holocene, our safe operating space ... We are in the middle of an “extinction-type event”, a planetary accident.