C. Natural Hazards Mitigation and Adaptation

• Natural hazard


  A natural process and event that is a potential threat to human life and property
• Types of natural hazards

  • Geologic Hazards
  • Hydrometeorological Hazards
  • Coastal Hazards
• Disaster


  A hazardous event that occurs over a limited time span in a defined area. Criteria for a natural disaster are: 10 or more people killed, 100 or more people affected, a state of emergency is declared, international assistance is requested
• Catastrophe


  A massive disaster that requires significant expenditure of money and a long time (often years) of recovery to take place
• Geologic cycle


  A collective term used to describe the complex interactions between the component sub-cycles of tectonic, rock, hydrologic and biogeochemical cycles
• Tectonic cycle


  • Involves the creation, movement, and destruction of tectonic plates. It is responsible for the production and distribution of rock and mineral resources invaluable to modern civilization, as well as hazards such as volcanoes and earthquakes
• Rock cycle


  • The largest of the geologic sub-cycles, and is linked to other sub-cycles. The rock cycle is a fundamental concept that depicts the ever changing transition through geologic times of the three (3) main types of rocks: igneous, sedimentary, and metamorphic
• Hydrologic cycle


  • The movement of water from the oceans to the atmosphere and back again to the oceans
• Biogeochemical cycle


  • The transfer or cycling of a chemical element or elements through the atmosphere, lithosphere, hydrosphere, and biosphere
• Geologic hazards

  • Earthquakes
  • Landslides
  • Volcanic Eruptions
• Earthquake


  The trembling of the Earth's surface that occurs when the energy in the form of strain in rock layers is released
• Earthquake features

  • Epicenter - place on the surface of the earth above where the ruptured rocks broke up to produce an earthquake
  • Focus - point of initial breaking or rupturing within the earth
  • Hypocenter - directly below the focus
• Earthquake measurements

  • Intensity - effects of ground motion on people and structure
  • Magnitude - amount of energy an earthquake released
  • Moment magnitude - indicates the size of the earthquake with a decimal number
• Landslide


  A downslope movement of a mass of rock, debris, earth, or soil
• Volcanic eruption


  One of Earth's most dramatic and violent agents of change. Volcanic activity is directly related to the plate tectonics, with most volcanoes located near the plate boundaries

  
• Magma


  Molten rock under the earth's crust
• Lava


  Molten rock erupted by a volcano to the earth's surface
• Vent


  Opening of a volcano through which lava and other volcanic materials are extruded onto the surface
• Ring of Fire


  An area where large number of earthquakes and volcanic eruptions occur in the basin of the Pacific Ocean

  
• Classifications of volcanoes

  • Active - currently erupting or showing signs of unrest
  • Dormant - currently not active, but could become active again
  • Extinct - considered unlikely to erupt again
• Volcanic eruption


  When magma, gases, or steam break through vents in the Earth's surface
• Mitigation and adaptation for geologic hazards

  • Earthquakes
  • Landslides
  • Volcanic Eruptions
• Volcanic eruption mitigation and adaptation

  1. Forecasting

  2. Education and Evacuation

  
• The Geohazard Mapping and Assessment Program - is an on-going priority program of the Department of Environment and Natural Resources (DENR), which is being implemented by the Mines and Geosciences Bureau (MGB). Its main objective is to identify areas in the country which are susceptible or vulnerable to various geologic hazards
• Hydrometeorological hazards

  • Cyclones
  • Monsoons
  • Flooding
  • Tornado
• Mines and Geosciences Bureau (MGB)


  Its main objective is to identify areas in the country which are susceptible or vulnerable to various geologic hazards. The program also seeks to provide information to various stakeholders in order to lessen or mitigate the impact of these events.
• Hydrometeorological hazard


  A process or phenomenon of atmospheric, hydrological or oceanographic nature that can endanger human lives and threaten human property
• Types of hydrometeorological hazards

  • Cyclones
  • Monsoons
  • Flooding
  • Tornado
• Cyclones


  Coined form the Greek word meaning "coil of snake". An area or center of low atmospheric pressure characterized by rotating winds
• Types of cyclones

  • Tropical Cyclones
  • Extratropical Cyclones
• Extratropical Cyclones


  Develop over land or water in temperate regions between 30° and 70° latitude
• Cyclone intensity


  Indicated by the cyclone's sustained wind speeds and lowest atmospheric pressure
• Terminology for strong tropical cyclones

  • Hurricanes (in the Atlantic and Pacific Oceans)
  • Typhoons (in the Pacific Ocean west of International Dateline)
• Tropical cyclone


  A general term for large thunderstorm complexes rotating around an area of low pressure that has formed over warm tropical or subtropical ocean water
• Stages of tropical cyclone development

  • Tropical disturbance
  • Tropical depression
  • Tropical storm
  • Hurricane/typhoon
• Hurricane/typhoon


  • Requires a tremendous amounts of heat to develop and generally form only where the sea surface temperature is at least 26°C
  • To be classified as a hurricane/typhoon, a tropical cyclone must have sustained winds of at least 119 km per hour somewhere in the storm
• Features of a Hurricane/Typhoon

  • Rainbands
  • Eyewall
• Effects of Cyclones

  • Flooding
  • Thunderstorms
  • Tornadoes
  • Storm surge
  • Heavy rains
  • High winds
• Monsoon


  A climate that has an apparent seasonal shift of prevailing winds between winter and summer, notably in tropical Asia, Australia, Africa, and the Indian Ocean
• Trade winds


  Generally come from the east and prevail during the rest of the year whenever the NE monsoons are weak