2 DRRR

• Hydrometeorology


  The study of the atmospheric and terrestrial phases of the hydrological cycle with emphasis on the interrelationship between them. It deals with the transfer of water and energy between land surface and the lower atmosphere.
• The geological location of the Philippines does not only pose geological threats but also Hydrometeorological hazards.
• The Philippines is in the Northern Hemisphere, which is above the equator.
• Intertropical Convergence Zone (ITCZ)


  The area near the equator where trade winds meet. Trade winds found flow in opposite directions and this is the reason that the strong whirling of winds happen. As a result of this swirling movement, frequent natural hazards in the atmosphere and ocean takes place.
• Typhoon


  Intense circulating winds with heavy rain over tropical waters and land. Typhoons are actually tropical cyclones whose winds have reached more than 118km/h, which is why it is describe as "intense".
• Typhoon

  • Northwest Pacific – Typhoon
  • Atlantic and Northeast Pacific – Hurricane
  • Northern Indian Ocean - Cyclone
• Thunderstorm


  A storm characterized by heavy rain with the presence of thunder and lightning. Thunderstorms may not have strong winds in contrast with typhoons.
• Cause of thunderstorms


  There is an uneven distribution of heat in the air and on land. The heat from the surface of Earth flows upward and the cold air from the atmosphere sinks to the ground.
• Hazards associated with thunderstorms

  • Heavy rainfall that can lead to flooding
  • Lightning that can electrocute humans and livestock and damage electrical facilities
  • Air turbulence which can displace or disorient a flying aircraft
  • Fire that can burn building an vegetation
• Flood


  The presence of excessive water on a supposedly dry land. It can be caused by continuous heavy rain or poor drainage. Low-lying areas are prone to flooding because they receive all the water coming from higher elevations.
• Flash flood


  A rapid flow of water on saturated soil or dry soil or any foundation that has poor absorption capability. This usually takes place in slopes such as mountains, volcanoes, and waterways where the peak of maximum force takes place downstream. Flash floods are usually caused by extensive rainfall but can also be induced by man-made structures such as water overflows from a dam.
• Storm surge


  The irregular sea-level rise during tropical cyclone or "Bagyo" occurs. When tropical cycle reaches the coast, powerful winds forces the ocean water over the coastal low-lying areas, which can lead to flooding.
• Tornado


  A rapidly rotating column of air that is in contact with the air and land. Its rotational movement is so violent that it can pick up objects from the ground and sling them away at far places.
• According to PAGASA (2011), an average of 12-24 tornadoes hit the country every year, mostly occurring in flat terrains such as Mindanao and Central Luzon, especially Nueva Ecija and Bulacan.
• El Niño


  The large-scale warming of the ocean and the atmosphere across the central and east-central Equatorial pacific. This event begins with the heating up of the Pacific Ocean near the equator. Trade winds in the ITCZ would move the heated water westward towards Southeast Asia, including the Philippines, while some global winds blow the warmer waters and air towards the western portion of the Americas.
• Effect of El Niño

  The winter seasons of Canada and western portion of the United States become warmer than the average temperature. In like manner, warming takes place in the Philippines during the cold season of December.
• La Niña


  The sea surface temperatures during this period become lower by 3 – 5 degrees Celsius. Cyclones formed during this time shift westward going to the direction of China. In effect, the Philippines is affected by the excessive rainfall and cold temperature.
• Tools for Monitoring Hydrometeorological Hazards

  • Doppler Radar
  • Automated rain gauge
• Doppler Radar


  Used to measure important weather parameters such as amount of rainfall and direction, speed, and intensity of wind. These data are used for weather conditions and upcoming typhoon weeks before the occurrence.
• Automated rain gauge


  Usually installed in telecommunication cell sites to observe and locate areas with excessive amount of rainfall. This is used to detect for possible flooding and flashfloods.
• Northwest Pacific

  -typhoon