tectonics, topic 3 Flashcards
Preventing disaster risk management
- strategies to prevent building from toppling due to groundshaking of an EQ
- implementing hazard-resistant building to withstand hazards
ie Taipei 101, spherical damper (approx 660 00kg) -> counter swaying of building
Land use regulation & planning to reduce exposure
- authorities regulate the development and use of land to reduce exposure to tectonic hazards
- use data gathered from hazard maps (suggests level of risks &likely extent of disaster), govt implements legislation
—> decreases loss of lives and damage to property
effectivetiveness of land use planning
YES: wall offers some protection to hinder land, reduce loss of lives
NO: tsunami waves could crash thru wall, regulations costly (govt compensates ppl who move), existing owners reluctant to move (belief that _____ might not happen)
eg DCs vs LDCs
Japan built 10 metre-high sea wall near the coast
BUT difficult in Mumbai- high rural-urban migration, lacks technology and financial resources to improve situation
[poverty causes ppl to construct their houses illegally on EQ prone areas -> suffer devastating effects of EQ]
Hazard resistant building designs
- advanced engineering (EQ resistant tech) applied in building infrastructure to withstand shaking, risk of collapse & fire risks
- use shock absorbers or dampers in building to absorb vibrations
- reinforcing buildings using diagonal cross braces to retain building shape during vibration
- bridge columns strengthened with encased steel jackets
- loose earth anchored to solid rock to reduce sliding
effectiveness of hazard-resistant building designs
YES: DCs- Japan, minimised collapse of infrastructure, reduced risks of fire outbreaks, lower death toll recorded and restoration costs reduced
NO: costly to incorporate (tech and professional advancement needed), remains unproven until severe EQ strikes to validate its effectiveness
eg DCs vs LDCs
Taiwan: Taipei 101 has a spherical damper that swings in opposite direction of sway of building, reduces the sway of building and threat of building collapsing
Haiti: 2010 EQ, area’s limited infrastructure devastate due to insufficient revenue & lack of expertise in advanced tech in infrastructure development, roads badly destroyed hampering aid from reaching victims
Use of technology (monitoring and warning systems)
- monitoring and warning systems builds community resilience as they reduce the vulnerability of people by providing an advance warning system
- precise forecasting may not be possible so scientists developed Earthquake Early Warning (EEW) systems which use a sensor of monitors
+ seismic waves detected by seismometers
+ seismometers transmit signals to a processing centre to determine size and location of shaking
+ alert sent to smart devices (mobile phones) informing ppl of when seismic waves might reach them
effectiveness of monitoring and warning systems
YES: few secs of advanced warning can be critical in saving lives- gives time for ppl to respond & evacuate quickly, EQ sensors help identify risk areas allowing aid to be directed wheremost necessary
NO: costly to install and maintain, subjected to interference- noise or lighting —> false alarm, not give accurate warnings if multiple EQ occurs, false alarms like tsunami when waves are fall
eg DCs vs LDCs
Japan: warning system (about 1000 seismometer ard country) for impending 2011 Tohoku EQ alerted millions of ppl a min before EQ struck, procedures of EQ drills were followed & speedy evacuation saved some lives
Indonesia: Pacific Tsunami Warning centre from Hawaii detected & issued warning of possible submarine EQ in Sumatra and tsunami in Indian Ocean(2004), Jakarta officials paralysed in relaying warning signals to citizens speedily due to lack of basic relay system resulting in massive loss of lives
Increasing community preparedness thru education & evacuation drills
- create awareness, reduces panic & ensure proper procedures are followed
- ppl know what to do during emergencies-> moving to safe locations, listening to instructions & practising first aid
- reduce likelihood of them being trapped in collapsed buildings & reduce potential loss of lives
Public awareness thru education: provides ppl with knowledge of hazards & how to respond to them thru training, campaigns & leaflets issued by authorities; eg taking temporary shelter from volcanic ash during eruption- sealing windows & doors
First aid training: enables ppl to administer basic medical care to the injured & keep them mobile so that they can evacuate when needed
Evacuation drills: enables ppl to be familiar with evacuation procedures and routes, reduces likelihood of them being trapped in collapsed buildings; for volcanic eruptions drills wld familiarise them to avoid areas downwind and river alleys (tephra carried by wind & gravity)
effectiveness of education & evacuation drills
YES: 1st September, emergency drills conducted in Japan to commemorate Disaster Prevention Day- high magnitude EQ stimulated. emergency drills in Japan aimed at stepping up mental preparedness on how to react during disaster (save many lives)
NO: drills designed based on magnitude of past events-> might not be realistic shld a more serious EQ occur; procedures only effective if there’s sufficient time to evacuate- difficulty in predicting EQs accurately results in insufficient time to evacuate
eg DCs vs LDCs
Japan: 2011 Tohoku EQ & tsunami- practice drills and evacuation plans were inadequate (large scale disaster), however procedures of EQ drills were followed when warning systems alert ppl- sch children & adults behaved calmly wearing helmets & going to emergency shelters —> unnecessarily loss of lives
Haiti: no prior warning to 2011 EQ, everything thrown into chaos, dead bodies strewn everywhere. Haitians weeping in the streets searching for help in vain & walking ard in shock
[challenges] extent of community’s resilience
- lack of technological and financial resources
+ reduce vulnerability (hazard resistant building designs)
+ exposure to tectonic hazards (land use planning)
+ recover from impacts of disaster
eg Dhaka, Bangladesh - 30% of Bangladeshi live below poverty line, country’s resources devoted to economic development
- 21% of buildings in Dhaka, easily damaged and reinforced
- 77% reinforced but not EQ resistant
—> Bangladesh vulnerable to impacts of EQs
[challenges] capability of community to organise itself
- limited capability
+ lack of efforts to train & education community to respond & recover from tectonic disasters
+ political instability (civil unrest)
+ corruption- loss of funding to build community resilience
eg 2010 Haiti EQ (Mw 7.0) ~220, 000 deaths - no measures put in place to educate Haitians on what to do during disaster
- no network of community healthcare workers (limited medical & emergency response)
- poor law enforcement led to looting
- chaos & unrest (survivors found it hard to take care of themselves)
Search & rescue
- reduce time taken to locate & evacuate survivors (requires skilled rescue officers & specialise equipment- heat sensors & listening devices)
- locate survivors more effectively
- reduces potential loss of lives , survivors trapped in collapsed buildings can located & rescue or they wld succumb to their injuries (‘crush’ syndrome, dehydration or loss of blood)
eg 2011 Tohoku EQ (Mw 9.0) - lives saved after 2 was of being trapped
- rescue teams used sniffer dogs & heat sensors and successfully rescued. any trapped victims
Timely evacuation
EARTHQUAKES
- buildings & infrastructure collapse, ppl need to vibe evacuated quickly to open spaces to avoid being trapped under collapsed buildings
- powerful aftershocks may cause weakened buildings (from EQ) to collapse, trapping ppl inside them
- basic services disrupted, ppl need to be evacuated to temporary shelters where food, water & medical supplies are provided
eg 2011 Tohoku EQ (Mw 9.0)
- Kamaishi, nearly all 3,000 students survived
- students evacuated to higher groundwater EQ struck, saved them from tsunami caused by EQ
TSUNAMI WAVES
- ppl need to be evacuated to higher ground & away from the coast
VOLCANIC ERUPTIONS
- lahars, pyroclastic flows, lava flows & tephra can cause loss of lives
- ppl need to be evacuated from danger zone ard volcano
eg 2010 Mt Merapi eruption
- aft warning issued by scientists, Indonesia’s authorities organised massive evacuation efforts comprised of >700 evacuation centres
- quick & massive evacuation efforts credited for saving >10,000 lives
Provision of basic social & psychosocial services- safe & clean drinking water
CAUSES: contamination
- ground shaking from EQ can router water pipes, cutting off or contaminating water supplies
- volcanic ash can pollute water sources (rivers & reservoirs)
IMPACTS: water-borne diseases
- occurs when affected communities drink from contaminated water to avoid dehydration
- safe drinking water distributed in forms of large water tankers or plastic bottles (sourced locally or supplied by international community)
eg 2010 Haiti EQ (Mw 7.0)
- disrupted water supply in Port-au-Prince
- international community of Red Cross set up water supply for 12,000 ppl by trucking water into the capital daily
Provision of basic social & psychosocial services- safe, nutritious, access & appropriate food distribution
CAUSES:
- food shops damaged/forced to close, food distribution system disrupted due to damage of crops
- food not suitable for consumption when frozen food turns bad due to damaged storage equipment
IMPACTS:
- emergency supply of food locally (govt has food stored in huge warehouses), regionally (brought in from elsewhere in country), internationally (from abroad)
- prevent hunger & starvation
eg 2017 Mt Agung eruption in Bali, Indonesia
- locals, international NGOs, and govt collective sent vehicles laden with food to help >75,000 ppl who fled the island
