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TOPIC 3 – DISASTER RISK MANAGEMENT (DRM), ^The greater the vulnerability…

- - - - It is determined as a product of the interaction between tectonic hazard, vulnerability and exposure to earthquakes and volcanic eruptions.
  - - - Hazards such as tsunamis can result in injuries and loss of lives as people drown and get hit by fast moving debris carried by the waves
      - People maybe homeless as houses are destoryed. They may be forced to live in temporary housing which lacks proper sanitation, resulting poor standards of living
      - The sea water brought by the tsunami may contaminate wells and other sources pf drinking water, causing water pollution. This may result in the spread of diseases such as cholera.
      - People may suffer from psychological trauma from the loss of their homes or loved ones. In addition, the constant threat of losing thier lives in the areas can affect their mental well-being.
    - - Landslides casued by volcanic eruptions can bury huge areas of forests and wetlands, destorying entire ecosystems and causing biodiversity loss.
      - All those debris pollutes rivers, killing aquatic lifes
      - Debris may block reviers, causing floods that can damage nearby ecosystems
    - - The hazards can cause destruction of homes and properties
      - People may suffer financially as it is costly to repair or rebuild their damaged homes.
      - Business owners can lose incomes caused by damage to their properties
      - Goverment need to spend money to repair and rebuild becuase of the damage from tectonic hazards.
    - - As money is used for rebuilding, not in other areas such as infrastructure and education
        
        These costs are especially detrimental to developing countries where the need for development is highest, and where funds may be lacking
        
        Proverty reduction progress may be affected as people are driven into poverty and their standards of living drop when they lose their source of income and homes.
        
        Countries, economic growth may also be slowed down, affecting their development progress
        
        The entire tourism industry may be severely affected due to damage in their infrastructure, facilities and amenities, resulting in loss of revenue to people and the government.
        
        Farmers may be unable to irrigate due to the contamination of the water sources
        
        Fishermen lose their boats to tsunamis are not able to fish
        
        School & healthcare facilities may be damaged, disrupting social services to disadvantaged communities, resulting in a drop in their standard of living
        
        The 20004 Indian ocean tsunami pushed the proportion of people living below the poverty line in Aceh, Indonesia, from 30% to 50T. Many lost their homes, jobs and sources of income, hindering Aceh's development
  - - - Reduce disaster risks as it is happening
        
        Early monitering and warning systems for tsunami and earthquake. This enables timely evacuation and reduces the potential loss of lives
        
        Strategies
      - Managing the risk after it happens
        
        Strategies
        
        Insurance coverage, which offers financial payouts to rebuild when properties are damaged or destroyed. This bring about quicker recovery from the impacts of the tentonic hazard.
      - Prevent disaster risks before it happens
        
        Strategies
        
        Designing hazard-resistant buildings to ensure structures can withstand hazards and do not collapse easily, hence preventing disaster risks
        
        Taipei 101, a skyscraper built in an earthquake-prone zone. Which has a weighted damper near the top of the building to balance out ground shaking from earthquakes. Which reduces the sway of the building therefore reducing the threat of the building collapsing.
        
        Example
  - - - The social, econnomic and environmental consequences may be very bad
        
        Tech they affect too
        
        Yes money, better position to recover due to available resources
        
        No money to invest in earthquake-resistant building, collaption
        
        Investment & planning helps too.
- - - - Building design and
        construction and Soil and rock properties
        
        Population density and assets
        in hazard-prone area and distance from epiccentre
    - - Duration of shaking
        
        The
        greater the magnitude of the earthquake the more violent
        the shaking, and the longer it will last longer the duration of ground shaking the
        more damage an earthquake will cause This is because
        structures such as buildings and bridges are subjected to a
        longer period of stress hence they are more likely to collapse Thus people are more likely to be trapped by the
        collapsed infrastructure leading to more injuries and loss of lives
      - Time of shaking
        
        The time of shaking is also crucial in affecting the
        extent of disaster risks. The time of day influences the
        activities carried out by people and how they respond when an earthquake strikes.
        For instance, if people are asleep at night, they will be less alert and unable to evacuate quickly. Hence, they
        will more likely be trapped when buildings collapse, leading to more injuries and loss of lives. On the other
        hand, if people are at work or school during the day, they are more alert and able to evacuate quickly.
        Hence, they are less likely to become trapped, leading to less injuries and loss of lives.
    - - Quality of building design and construction
        
        The quality of building design and construction plays a huge
        part in determining the extent of disaster risks experienced by a place when an earthquake strikes. In general, the
        poorer the quality of building design and construction, the greater the disaster risk. Houses made of mudbrick walls and lack of support beams
        are more vulnerable to shaking compared to a house made of reinforced concrete with a strong foundation.
        
        are poorly built with low-quality materials such as
        zinc sheets used in slums, lack earthquake-proof reinforcements such as
        reinforced steel walls, do not follow rules designed to protect properties
        and lives in case of earthquakes building codes set by the authorities
      - Soil and rock properties
        
        Weak foundation can add to the vulnerability of a place
        to earthquakes. It can also potentially open the area up to secondary impacts of an earthquake, like
        liquefaction and landslides. Both landslides and liquefaction can cause a lot of
        damage to properties and can even result in the loss of lives if people are buried within the descending soil or
        drowned from the rush of liquified soil. In general, the softer the soil, the higher the disaster
        risks, the greater the vulnerability.
        
        When seismic waves travel from hard rocks to soft soil,
        the waves are amplified. Passing from rock to soil, the waves slow down but
        become bigger. Soft, loose soil will shake more intensely than hard rock, increasing the likelihood of
        buildings and bridges collapsing. As a result, people are more likely to become trapped
        in buildings, leading to more injuries and loss of lives. On the other hand, solid rock is much more compact
        and will shake less intensely. For example, as large areas of Port-au-Prince, Haiti, lie
        on layers of relatively soft soil, when the Mw 7.0 earthquake occurred in 2010, the seismic waves were
        amplified. This led to the collapse of many buildings, leading to more than 220,000 people
        losing their lives.
  - - - Availability of surface and ground water
        in the development of lahars Prevailing wind conditions affecting
        direction and distribution of tephra
        
        Presence of human settlements
    - - Low silica magma
        
        Less viscous
        
        Gentle effusive
        
        Lava can flow far from the volcano before
        cooling. Damage infrastructure and properties over large areas within the
        geographic region of the volcano. Rarely kill people as they can avoid the pathway
        of lava.
        
        2018 eruption of Kilauea in Hawaii caused
        24 injuries, destroyed 600 homes, US$800 million in property damage.
      - high silica magma
        
        More viscous
        
        Explosive eruption
        
        May form highly destructive pyroclastic
        flows, causing widespread damage to infrastructure, injuries and loss of lives.
        Volcanic bombs may strike people and properties, result in injuries and deaths.
        
        2010 eruption of Mount Merapi in
        Indonesia. Pyroclastic flows travelled 3km down the heavily populated mountain
        sides. Volcanic bombs spread about 10km. 350, 000 people were evacuated and
        about 350 people were killed.
    - - Availability of surface and groundwater
        
        Large quantities of water are required for lahars to develop.
        The greater the availability of surface and groundwater, the more likely lahars will develop. The availability of water in
        an area depends on:
        
        Rapid melting of snow and ice on the volcano’s
        summit just before or during an eruption
        
        Groundwater released through cracks and fractures
        during a volcanic eruption
        
        Heavy rainfall
        
        Existing rivers or lakes nearby
        
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      - Prevailing wind conditions
        
        Prevailing wind refers to the dominant wind direction.
        The strength and direction of the prevailing wind affect the direction and distribution of ashfall and tephra, which
        influences the extent of disaster risks.
        
        During an explosive eruption, some tephra is deposited
        close to the volcano. The extent of these deposits depends on the prevailing wind strength and direction.
        
        In general, the direction of the prevailing wind
        influences the direction of ashfall and tephra flow, and the extent of damage.
        
        The strength of the prevailing wind also affects the
        extent of areas affected by ashfall and tephra. The higher the speed of the prevailing wind, the further the
        ashfall and tephra are likely to be dispersed. More areas will be affected, causing more people and properties to
        become vulnerable.
        
        2011 Eruption of Shinmoedake, Japan. The eruption
        plume was bent over and directed by the local prevailing winds, and subsequent ashfall.
    - - Presence of human settlements
        
        If a volcanic eruption occurs in an area that is populated with dense human settlement, the disaster risk from a
        volcanic eruption is high.
        
        This is because there is a greater potential for the loss of lives and destruction of properties than if the volcanic
        eruption occurred underwater, which is devoid of human settlement.
        
        volcanic areas provide advantages and opportunities such as:
        
        Rich, fertile volcanic soils which are ideal for farming
        
        Harnessing geothermal energy from naturally occurring hot water and steam, which can be harnessed to
        provide electricity
        
        Valuable minerals such as sulfur which can be mined
        
        • An example of an active volcano where human settlements can be found is Mount Sinabung in Indonesia. It has
        experienced several explosive eruptions since 2010.
  - - - Distance from epicentre
        
        In general, the nearer the city is to the epicentre, the
        greater the number of people and buildings exposed to the hazard, hence the greater the disaster risks.
        When the city is nearer to the epicentre, less energy is absorbed by the rocks before the seismic waves reach
        the city. Hence, the seismic waves reaching the city will be stronger, causing more violent shaking. As a result,
        buildings and bridges are more likely to collapse, and people will more likely become trapped, leading to more
        injuries and loss of lives.
        
        For example, the 2010 earthquake in Port-au-Prince, Haiti
        (Mw 7.0) resulted in more than 220,000 deaths as its epicentre was only about 25km west of the city
      - Population density refers to the number of people per unit
        of area, usually quoted per square kilometre. In general, the higher the population density in a hazard-
        prone area, the greater the number of people and buildings exposed to the earthquake, hence the greater the disaster
        risks.
        
        In cities, where population density is high, places such as
        apartment buildings, offices, trains and buses are often crowded with people. This puts large numbers of people at
        risk when an earthquake happens. One example is Port-au-Prince in Haiti which is a densely populated city.
      - For example, in 1995, the densely populated Japanese
        industrial city of Kobe was severely affected by a Mw 6.9 earthquake, which killed over 6,000 people and injured
        about 40,000 people. The population density then was about 3,000 people per square kilometre.
- - - - How do monitoring and warning systems reduce vulnerability?
        
        How does increasing preparedness for response and recovery build community resilience?
        
        Strategies to increase preparedness include: Raising public awareness of hazards through education, Provides people with the knowledge of the hazards, and how to respond to them. For instance, taking temporary shelter from volcanic ash during an eruption, and sealing doors and windows. Or informing people of what they should do when they receive an earthquake early warning (EEW) through public education.
        
        First-aid training, Enables people to administer basic medical care to the injured and keep them mobile so that they can evacuate if needed.
        
        Conducting evacuation drills, Enables people to be familiar with evacuation procedures and routes. This reduces the likelihood of them being trapped in collapsed buildings. For volcanic eruptions, the drills would familiarise them to avoid areas downwind and river valleys, as tephra will be carried by wind and gravity.
        
        For tsunamis, the drills would familiarise people with the designated tsunami inundation zones and the marked evacuation routes, so they can avoid the tsunami waves.
        
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        Developing monitoring and warning systems will allow the community to be given some warning that a tectonic hazard is about to occur. They can seek shelter or evacuate to a safer place, reducing the community’s susceptibility to tectonic hazards.
        
        While precise forecasting may not be possible, scientists are developing Earthquake Early Warning (EEW) systems which use a network of sensor monitors. When an earthquake occurs, seismic waves are detected. An alert is then sent to smart devices such as mobile phones, informing people of when the seismic waves might reach them.
        
        While the advance warning may only be a few seconds before the earthquake strikes, those few seconds can be critical in saving lives, as it gives time for people to respond and evacuate quickly. The earthquake sensors also help identify risk areas during an earthquake event, allowing aid to be directed where most necessary.
        
        For example, during the 2011 Tohoku, Japan magnitude 9.0 earthquake, the monitoring and warning system saved thousands of passengers in 19 bullet trains which were running at top speeds. All trains were able to stop before the earthquake struck.
      - Hazard-resistant building designs include the use of counterweights and/or cross bracing. These designs allow buildings to withstand shaking during an earthquake.
        
        Earthquake-resistant building design that can withstand ground shaking include: Using shock absorbers or dampers in buildings to absorb vibrations. Reinforcing buildings using diagonal cross braces to retain building shape during vibration.
        
        Earthquake-resistant building designs can build community resilience as they reduce the vulnerability and likelihood of buildings collapsing.
        
        Taipei 101 is a skyscraper built in an earthquake-prone zone. It has a mass damper that swings in the opposite direction of the sway of the building when an earthquake occurs, reducing the sway of the building and the threat of the building collapsing.
    - - Hazard maps can: Suggest levels of risk (high, medium, or low) based on the likelihood of a disaster occurring. Indicate the likely extent of disasters, by predicting earthquake magnitude.
        
        For instance, a coastal, low-lying area in an earthquake prone zone that is susceptible to flooding by tsunamis will be allocated to low-value use, such as recreational parks. These high disaster risk areas will not be allocated for high- value commercial or social use such as medical facilities. As a result, the community’s exposure to hazards is reduced.
        
        For example, after a tsunami hit Japan in 1933, residential land use along the coast was shifted to newly developed areas on higher ground, including the entire community of Touni-hongo village. When the 2011 Tohoku earthquake and tsunami struck, houses on low-lying ground were flooded and washed away, but the waves did not reach those on higher ground.
  - - - The availability of resources can determine the ability of the community to reduce exposure to hazards and to recover from the dangers associated with tectonic hazards.
        
        Having plans and making these plans work require considerable funds and coordination between various stakeholders.
        
        Developing countries often lack the resources to build community resilience. This is because the governments of developing countries may choose to prioritise more immediate and pressing needs such as economic development and housing shortage, instead of preparing for and dealing with tectonic disasters.
        
        Bangladesh, a developing country, lies along a plate boundary. As about 30% of Bangladeshis live below the poverty line, much of the country’s resources are devoted to economic development. It has been found that 21% of buildings in the capital, Dhaka, are easily damaged and unreinforced. 77% are reinforced but have not been designed to resist earthquakes. This makes Dhaka very vulnerable to the impacts of earthquakes.
    - - A lack of capability of the community to organise itself may limit the community’s ability to respond and recover from tectonic disasters.
        
        The capability of the community to organise itself
        may be limited by various factors such as:
        
        Lack of efforts to educate and train the community to respond and recover from tectonic disasters.
        
        Political instability, such as civil unrest and corruption, which may lead to loss of funding meant to build community preparedness.
        
        During the 2010 earthquake in Haiti (Mw 7.0) which resulted in more than 220,000 deaths. The community in Haiti was not able to organise itself for disasters as there were no measures put in place to educate Haitians on what to do during a disaster. It had no network of community healthcare workers, which limited the medical and emergency response. Poor law enforcement led to looting becoming prevalent as the need to survive became urgent. There was chaos and unrest as survivors found it hard to take care of themselves and recover from the disaster.
- - - - Search and Rescue
        
        Search and rescue refers to actions taken by governments and relief groups to find and save victims trapped in buildings or disaster zones.
        
        To reduce the time taken to locate and evacuate survivors, search and rescue efforts will require skilled rescue officers with specialised equipment such as heat sensors and listening devices.
        
        This strategy reduces the potential loss of lives as survivors trapped in collapsed buildings can be located and rescued. Otherwise, they would succumb to their injuries from ‘crush syndrome’, dehydration, or related injuries.
        
        During the 2020 Aegean Sea, Turkey earthquake (Mw 7.0), more than 8,000 search, rescue and first aid teams were deployed and over 106 people were rescued.
      - Provision of basic social and psychosocial services
        
        Many people are displaced by disasters. The provision of shelters with adequate food and clean water is essential for survival. Clean water is especially important as there needs to be a management of the spread of waterborne diseases after an earthquake.
        
        Water
        
        During an earthquake, ground shaking can rupture water pipes, cutting off or contaminating water supplies. Volcanic ash can pollute water sources (e.g. rivers and reservoirs). Hence, there could be a water shortage.
        
        Clean water can prevent dehydration or water-borne diseases, which may occur when affected communities drink from contaminated sources of water.
        
        Safe drinking water may be distributed in the form of
        large water tankers or plastic water bottles.
        
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        Food
        
        After an earthquake or volcanic eruption, there may be
        food shortages and survivors may not have access to fodd at all.
        
        Food shops may be damaged or forced to close, the food distribution system may also be disrupted due to damage to crops.
        
        Even when food is available, it may not be safe for consumption. Frozen food turns bad when storage equipment is damaged.
        
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        Healthcare
        
        Psychosocial services
        
        Psychosocial services address the ongoing psychological needs of individuals with disorders, as well as their families and caregivers.
        
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        Healthcare services include the availability of and access to medicine, doctors and hospitals.
        
        These services are likely to be disrupted when hospitals and transportation are damaged, causing a shortage of healthcare services.
        
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        After the Haiti earthquake in 2010, there was a related outbreak of cholera. Water supply and waste disposal infrastructure was destroyed in the earthquake resulting in contaminated water. In the days and weeks following a disaster, affected communities require basic social and psychosocial services.
      - Timely evacuation involves moving people away from areas at risk of hazards quickly.
        
        Buildings and infrastructure may collapse. Hence, people need to be evacuated quickly from buildings to open spaces, to avoid getting trapped under collapsed buildings.
        
        Powerful aftershocks can occur soon after an earthquake. Buildings and structures already weakened from initial shaking may collapse due to aftershocks, trapping people who are still in them.
        
        Basic services may be disrupted, hence, people need to be evacuated to temporary shelters where food, water, medical supplies are provided.
        
        For example, during the
        2011 Tohoku, Japan earthquake (Mw 9.0) in Kamaishi city, nearly all 3,000 students in the city survived. Students were evacuated to higher grounds immediately after the earthquake struck, saving them from the tsunami caused by the earthquake.
        
        Earthquakes
        
        Tsunami waves
        
        People need to be evacuated to higher ground and away from the coast.
        
        Volcanic eruptions
        
        Lahars, pyroclastic flows, lava flows, and tephra can cause loss of lives. Hence, people need to be evacuated from the danger zone around the volcano.
        
        For example, in 2010, after a warning of Mount Merapi’s imminent eruption was issued by scientists, Indonesia’s authorities organised massive evacuation efforts that comprised more than 700 evacuation centres. The quick and massive evacuation efforts were credited for saving more than 10,000 lives.
  - - - Basic medical infrastructure may be destroyed, hospitals and clinics may not be available. It is necessary to provide medical services for the injured such that they do not succumb to their injuries.
        
        Facilities and living conditions can be improved by constructing
        hazard-resistant buildings and infrastructures.
        
        Similarly, we can retrofit surviving buildings and infrastructure with hazard-resistant features.
        
        This strategy meets the long-term needs of the affected communities. It allows residents to eventually return to their original homes, instead of having to move away.
        
        This keeps communities and relationships intact even after the disaster. These strategies enable the affected communities to rebuild their lives after the disaster, as well as minimising their vulnerability and exposure to tectonic hazards.
        
        For example, following the 2011 Tohoku, Japan earthquake, about 500,000 people were originally displaced by the tsunami. By 2016, the vast majority had been rehoused in settlements with enhanced tsunami- proof features. In the port town of Rikuzentakata, the ground level of sites for new houses was raised by 10 metres, and two more protective seawalls that are 3 metres and 12.5 metres high were built.
  - - - The lack of domestic resources, including technology and finances can hamper the ability to manage disasters and for society to recover in these disaster-stricken areas, especially for developing countries.
        
        The country may not have the financial or technological resources to cope with the need to rebuild the infrastructure that has been destroyed in the disaster.
        
        For example, after the 2010 Mw 7.0 earthquake in Haiti, the lack of resources hampered the disaster management efforts. There was a critical shortage of ambulances to transport the injured, and heavy machinery to remove the rubble from collapsed buildings. As a result, the rescue team spent many hours removing tons of rubble manually with hammers or rods to pull the trapped people under collapsed buildings.
      - What are the challenges in engaging relevant stakeholders to collaborate and integrate disaster management strategies into their practices?
        
        Disagreements from other stakeholders on
        disaster management strategies.
        
        Stakeholders underestimate or lack awareness of the disaster risks and the need for certain disaster management strategies.
        
        The high cost of integrating disaster management strategies into their practices.
        
        Local communities might be reluctant to purchase insurance for tectonic disaster risks due to the high costs involved.
        
        Private insurance companies might also not be willing to offer such insurance policies because of the high financial commitment required.
        
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