Study Notes on Hydrometeorological Hazards and Preparedness

Hydrometeorological Hazards Overview

  • Hydrometeorological hazards refer to processes or phenomena of atmospheric, hydrological, or oceanographic nature.

  • Consequences:

    • Loss of life

    • Injury or health impacts

    • Property damage

    • Loss of livelihoods and vital services

    • Social and economic disruptions

    • Environmental damages

Types of Hydrometeorological Hazards

  • Common types include:

    • Tropical Cyclones (Typhoons/Hurricanes)

    • Thunderstorms

    • Hailstorms

    • Tornadoes

    • Drought

    • Heat Waves

    • Cold Spells

    • Heavy Snowfall

    • Floods/Flash Floods

    • Storm Surges

    • Avalanches

    • Blizzards

  • Hydrometeorological conditions can also contribute to other hazards:

    • Landslides

    • Wildfires

    • Locust plagues

    • Epidemics

    • Volcanic eruptions

Specific Hydrometeorological Hazards Defined

Cyclones

  • Definition: A cyclone is a powerful spinning storm characterized by strong winds and rain.

  • Characteristics:

    • Intense low-pressure systems

    • Strong spiral winds with counter-clockwise flow (northern hemisphere)

    • Hazards: Strong winds, heavy rainfall, widespread flooding, storm surges, landslides, mudflows

Classification of Cyclones

  • Tropical Depression: Winds from 35 km/h to 63 km/h

  • Tropical Storm: Winds from 64 km/h to 118 km/h

  • Typhoon: Winds exceeding 118 km/h

Typhoons

  • Definition: A typhoon is a large, powerful tropical cyclone.

  • Characteristics:

    • Rotates counter-clockwise over warm water in the Western Pacific

    • Damage due to thunderstorms, violent winds, torrential rain, floods, landslides

    • Known as hurricanes in the Atlantic and cyclones in the Indian Ocean

Thunderstorms

  • Definition: A violent local disturbance producing lightning, thunder, and heavy rainfall, possibly leading to tornado formation.

  • Formation: Caused by convection when warm moist air rises and cools, forming cumulonimbus clouds.

Tornado

  • Definition: A violent rotating column of air extending from a thunderstorm to the ground.

  • Characteristics:

    • Appearance: Visible condensation funnel, encircled by debris

    • Size: Varies; can be nearly transparent until debris is picked up

    • Usually develops in severe thunderstorms due to unstable warm air along cold fronts

Flash Flood

  • Definition: Rapid flooding of low-lying areas like washes, rivers, and basins.

  • Causes:

    • Heavy rain with severe thunderstorms

    • Tropical storm conditions

    • Ice melt

    • Collapse of natural or man-made dam

  • Timescale: Distinguished from regular floods by a rapid onset, usually within six hours.

Flood

  • Definition: Inundation of land not normally covered by water due to temporary rise of rivers, streams, or lakes.

  • Causes:

    • Heavy, prolonged rainfall

    • Storm surges

    • Debris jams

Storm Surge

  • Definition: Rise of seawater above normal sea level due to cyclonic winds and atmospheric pressure.

  • Mechanism: Water level is driven towards the coast and can affect vast stretches of land depending on the slope of the seabed.

El Niño and La Niña

Overview

  • El Niño and La Niña are significant weather patterns arising from ocean temperature variations in the equatorial Pacific.

  • They are opposite phases of the El Niño-Southern Oscillation (ENSO) cycle.

Sea Surface Temperature Anomaly

  • El Niño and La Niña typically last nine to 12 months; irregularly every 2 to 7 years.

Tools in Tracking Storms

Satellite Technology

  • Satellites provide real-time visualization of cyclone formation and path.

Doppler Radar

  • Radio Detection and Ranging technology used to track precipitation, determine speed and distance of storm activity.

  • Key functions include spotting clouds' movements and predicting storm paths based on reflection of radio waves.

Safety, Preparedness, and Mitigation

General Safety Protocols

  • Establish coordination with local disaster management councils.

  • Strengthen house resilience against severe weather.

Typhoon Preparedness

  • Learn about typhoon signs, warnings, and mitigation strategies.

During a Typhoon

  • Monitor reliable news sources, evacuate if necessary, stay indoors.

Post-Typhoon Rehabilitation

  • Provide immediate assistance to victims and check property for damages.

Thunderstorm Preparedness

  • Develop family plans, know local risks, and secure properties.

During Thunderstorms

  • Adopt position for lightning safety, stay indoors, unplug devices.

Tornado Preparedness

  • Establish family plans, conduct drills, and monitor weather updates.

Flash Flood and Flood Preparedness

  • Know flood risks, stay alert to weather changes, and prepare emergency kits.

During Floods

  • Stay informed, avoid floodwaters, and listen to alerts.

Storm Surge Preparedness

  • Identify evacuation routes, know surge risk zones, and participate in drills.

During a Storm Surge

  • Move to higher ground upon warnings, avoid steep areas prone to landslides.

Project NOAH and Local Initiatives

Project NOAH Overview

  • Developed to enhance disaster risk assessments, monitoring, and management to mitigate natural hazards within the Philippines.

  • Components include:

    1. Installation of automated rain gauges and water level monitoring stations.

    2. Disaster Risk Exposure Assessment.

    3. Improved geohazards mapping via LIDAR technology.

    4. Coastal hazards and storm surge assessments.

    5. Flood Information Networks for accurate early warnings.

    6. Local development initiatives for Doppler radar systems.

    7. Landslide sensors for earlyHydrometeorological Hazards Overview

      • Hydrometeorological hazards refer to processes or phenomena of atmospheric, hydrological, or oceanographic nature.

      • Consequences:

        • Loss of life

        • Injury or health impacts

        • Property damage

        • Loss of livelihoods and vital services

        • Social and economic disruptions

        • Environmental damages

      Types of Hydrometeorological Hazards

      • Common types include:

        • Tropical Cyclones (Typhoons/Hurricanes)

        • Thunderstorms

        • Hailstorms

        • Tornadoes

        • Drought

        • Heat Waves

        • Cold Spells

        • Heavy Snowfall

        • Floods/Flash Floods

        • Storm Surges

        • Avalanches

        • Blizzards

      • Hydrometeorological conditions can also contribute to other hazards:

        • Landslides

        • Wildfires

        • Locust plagues

        • Epidemics

        • Volcanic eruptions

      Specific Hydrometeorological Hazards Defined

      Cyclones

      • Definition: A cyclone is a powerful spinning storm characterized by strong winds and rain.

      • Characteristics:

        • Intense low-pressure systems

        • Strong spiral winds with counter-clockwise flow (northern hemisphere)

        • Hazards: Strong winds, heavy rainfall, widespread flooding, storm surges, landslides, mudflows

      Classification of Cyclones

      • Tropical Depression: Winds from 35 km/h to 63 km/h

      • Tropical Storm: Winds from 64 km/h to 118 km/h

      • Typhoon: Winds exceeding 118 km/h

      Typhoons

      • Definition: A typhoon is a large, powerful tropical cyclone.

      • Characteristics:

        • Rotates counter-clockwise over warm water in the Western Pacific

        • Damage due to thunderstorms, violent winds, torrential rain, floods, landslides

        • Known as hurricanes in the Atlantic and cyclones in the Indian Ocean

      Thunderstorms

      • Definition: A violent local disturbance producing lightning, thunder, and heavy rainfall, possibly leading to tornado formation.

      • Formation: Caused by convection when warm moist air rises and cools, forming cumulonimbus clouds.

      Tornado

      • Definition: A violent rotating column of air extending from a thunderstorm to the ground.

      • Characteristics:

        • Appearance: Visible condensation funnel, encircled by debris

        • Size: Varies; can be nearly transparent until debris is picked up

        • Usually develops in severe thunderstorms due to unstable warm air along cold fronts

      Flash Flood

      • Definition: Rapid flooding of low-lying areas like washes, rivers, and basins.

      • Causes:

        • Heavy rain with severe thunderstorms

        • Tropical storm conditions

        • Ice melt

        • Collapse of natural or man-made dam

      • Timescale: Distinguished from regular floods by a rapid onset, usually within six hours.

      Flood

      • Definition: Inundation of land not normally covered by water due to temporary rise of rivers, streams, or lakes.

      • Causes:

        • Heavy, prolonged rainfall

        • Storm surges

        • Debris jams

      Storm Surge

      • Definition: Rise of seawater above normal sea level due to cyclonic winds and atmospheric pressure.

      • Mechanism: Water level is driven towards the coast and can affect vast stretches of land depending on the slope of the seabed.

      El Niño and La Niña

      Overview

      • El Niño and La Niña are significant weather patterns arising from ocean temperature variations in the equatorial Pacific.

      • They are opposite phases of the El Niño-Southern Oscillation (ENSO) cycle.

      Sea Surface Temperature Anomaly

      • El Niño and La Niña typically last nine to 12 months; irregularly every 2 to 7 years.

      Tools in Tracking Storms

      Satellite Technology

      • Satellites provide real-time visualization of cyclone formation and path.

      Doppler Radar

      • Radio Detection and Ranging technology used to track precipitation, determine speed and distance of storm activity.

      • Key functions include spotting clouds' movements and predicting storm paths based on reflection of radio waves.

      Safety, Preparedness, and Mitigation

      General Safety Protocols

      • Establish coordination with local disaster management councils.

      • Strengthen house resilience against severe weather.

      Typhoon Preparedness

      • Learn about typhoon signs, warnings, and mitigation strategies.

      During a Typhoon

      • Monitor reliable news sources, evacuate if necessary, stay indoors.

      Post-Typhoon Rehabilitation

      • Provide immediate assistance to victims and check property for damages.

      Thunderstorm Preparedness

      • Develop family plans, know local risks, and secure properties.

      During Thunderstorms

      • Adopt position for lightning safety, stay indoors, unplug devices.

      Tornado Preparedness

      • Establish family plans, conduct drills, and monitor weather updates.

      Flash Flood and Flood Preparedness

      • Know flood risks, stay alert to weather changes, and prepare emergency kits.

      During Floods

      • Stay informed, avoid floodwaters, and listen to alerts.

      Storm Surge Preparedness

      • Identify evacuation routes, know surge risk zones, and participate in drills.

      During a Storm Surge

      • Move to higher ground upon warnings, avoid steep areas prone to landslides.

      Project NOAH and Local Initiatives

      Project NOAH Overview

      • Developed to enhance disaster risk assessments, monitoring, and management to mitigate natural hazards within the Philippines.

      • Components include:

        1. Installation of automated rain gauges and water level monitoring stations.

        2. Disaster Risk Exposure Assessment.

        3. Improved geohazards mapping via LIDAR technology.

        4. Coastal hazards and storm surge assessments.

        5. Flood Information Networks for accurate early warnings.

        6. Local development initiatives for Doppler radar systems.

        7. Landslide sensors for early monitoring.

        8. Weather hazard information via media and web portals.

      monitoring.

    8. Weather hazard information via media and web portals.