slide1 n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Natural Hazards PowerPoint Presentation
Download Presentation
Natural Hazards

Loading in 2 Seconds...

play fullscreen
1 / 24

Natural Hazards - PowerPoint PPT Presentation


  • 124 Views
  • Uploaded on

Natural Hazards. Malservisi@geophysik.uni-muenchen.de. Presentation on line at: www.geophysik.uni-muenchen.de/~malservisi/classes/NaturalHazards.htm. Class schedule:. NATURAL HAZARDS ??. A natural process that poses a threat to human life or property.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Natural Hazards' - zia-rodriguez


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide1

Natural Hazards

Malservisi@geophysik.uni-muenchen.de

Presentation on line at:

www.geophysik.uni-muenchen.de/~malservisi/classes/NaturalHazards.htm

slide4

NATURAL HAZARDS ??

A natural process that poses a threat

to human life or property

natural hazards global effects
Natural Hazards Global Effects

All these events can have a big impact both socially and economically on the affect societies and environment. Many times they have a global effects.

Some of global effects can be extreme:

Cretaceous Extinction: Asteroid impact and Volcanism; 85% of all species died in the End-Cretaceous (K-T, 65 million years ago) extinction.

Permian Mass Extinction: Cause not really know but probably associated with Climate Fluctuation, Glaciations of Gondwana and formation of Pangaea, or Volcanic Activity. 95% of marine species became extinct!!

natural hazards global effects1
Natural Hazards Global Effects

Examples of global effect:

Toba (Sumatra, Indonesia)

eruption ~75000 years ago.

Probably 5C global average

decrease in temperature

(combined with ice age).

Population of Homo Sapiens

From >100000 to <2000

Genetic bottleneck

natural hazards global effects2
Natural Hazards Global Effects

All these events can have a big impact both socially and economically on the affect societies and environment. Many times they have a global effects.

Some of global effects can be extreme:

Cretaceous Extinction: Asteroid impact and Volcanism; 85% of all species died in the End-Cretaceous (K-T, 65 million years ago) extinction.

Permian Mass Extinction: Cause not really know but probably associated with Climate Fluctuation, Glaciations of Gondwana and formation of Pangaea, or Volcanic Activity. 95% of marine species became extinct!!

natural hazards global effects3
Natural Hazards Global Effects

Examples of global effect:

Toba (Sumatra, Indonesia)

eruption ~75000 years ago.

Probably 5C global average

decrease in temperature

(combined with ice age).

Population of Homo Sapiens

From >100000 to <2000

Genetic bottleneck

natural hazards global effects4
Natural Hazards Global Effects

Examples of global effect:

Laki (Iceland) eruption 1783: 75% of livestock in Iceland died; 25% of the Iceland population died for the following famine; fluorine poisoning of animals as far away as Britain; ~1.5C diminution of the average year temperature in US and Europe (France Revolution??)

natural hazards global effects5
Natural Hazards Global Effects
  • Examples of global effect:
  • Santorini eruption+tsunami 1645 BC: Destruction of the Minonian culture (legend of Atlantis?)
  • Tambora, Indonesia 1815, average decrease of temperature in northern hemisphere ~0.7C; 1816 “year without summer” (snow in July in Washington DC).
  • ChiChi Earthquake, Taiwan 1999:
  • prices of computers chips double worldwide for few months
number of disasters
Number of Disasters
  • 10 or more people reported killed
  • 100 people reported affected
  • declaration of a state of emergency
  • call for international assistance

Bias: International

database created

in 1980s

IMPORTANT!!! This does not means that the number of events

are increasing (the number of earthquake for example is constant)

but the effects on human activity are increasing!!

number of disasters1
Number of Disasters

Another bias:

Disasters are related. For example the casualty of december 2004 are listed as tsunami (should we count them as earthquake?).

The casualty of 1998 Papa New Guinea are listed as earthquake since majority of damages were related to the earthquake, but the majority of the victims were related to a tsunami generated by a landslide generated by the earthquake.

total damages costs since 1900
Total damages costs since 1900

Wave

Drought

Volcano

Extreme Temp

Storm

Flood

Slide

Earthquake

For all the natural hazard the global costs have been increasing

total damages costs since 19001
Total damages costs since 1900

Wave

Drought

Volcano

Extreme Temp

Storm

Flood

Slide

Earthquake

In term of costs Earthquakes, Tropical Storms, and Floods are the most expensive “geological” hazards

Epidemic and Famine have been historically the most devastating in term of casualty

Plague in middle age killed 1 every 3 european, Spanish Flu Pandemic 1920 30 million

total damages vs population
Total damages vs Population

Increase in total damages correlate well

with increase in population

geographical distribution
Geographical Distribution

Earthquake Risk

Volcanoes

Tornado

Storms

Almost all the areas of the planet are affected by some kind of hazard

Stable interior of continent more “safe” but often not suitable to life

population distribution vs risk map1
Population distribution vs Risk map

The human population is concentrated in “risky areas”

We need water, topography is controlling the hydrological cycle

Often river flows in valleys controlled by fault position

Rivers are more “manageable” in flat costal regions.

Stable interiors of continents are often deserts.

We need soil: volcanoes produce excellent fertile soil. Water and

plants are essential in soil formations (see point 1). River flood

Planes have excellent soil brought by periodic floods

We need communications way: flat costal areas are often the only

suitable regions to build houses and roads.

We are too many and we start to build in places where we should not

Build and our ancestor were not building (river banks, beaches…)

population distribution vs risk map2
Population distribution vs Risk map

Active tectonic is a necessity to have

a planet where we can live!

We live in a dangerous planet but probably there is life

On Earth because our planet is dangerous!