Estimates

Box 2.2: Dynamics and evacuation patternsassociated with rapid-onset hazardsNational and local authorities have the primary responsibilityfor implementing evacuations as a protective measure.Given that fleeing quickly from the dangers inherent ina rapidly unfolding disaster can be highly risky, especiallywhen large numbers of people are involved, such evacuationsshould be well prepared for in advance, including theidentification of safe refuge areas.People with limited mobility because of age, illness ordisability or sickness, and children who become separatedfrom their carers require particular attention to ensure thatthey are adequately protected. 24Evacuations are normally undertaken on the assumptionthat they will be short-lived, but return depends on the effectsof a disaster in home areas and prospects for recovery. Torespect human rights and be lawful, authorities must ensurethe safety and health of those affected or at risk, and allmeasures must be taken to minimise the scale and durationof displacement and its adverse effects. 25Well-executed evacuations of people living in exposed areasare a vital life-saving measure. 26 Governments worldwidehave recognised the importance of effective early warningsystems to monitor threats and ensure that timely notice isgiven to all those potentially exposed. 27 Evacuations mustalso take into account the nature of different hazards, whichdo much to determine the timing and dynamics of initialdisplacement patterns.In the case of tropical storms, evacuations tend to takeplace over the hours and sometimes days before they areexpected to make landfall, and/or over similar timescalesafterwards. The onset of hurricanes and cyclones can be predictedin time to allow for prior large-scale evacuations, butthey may change strength and direction at the last minute.Tornadoes often develop with little warning, so shelteringin situ, often underground, tends to be the safest option. Insuch cases, people can still become displaced in the storm’saftermath if they lose their homes or the devastation to theircommunities is so widespread that they are forced to moveelsewhere, at least temporarily.Tsunami warnings provide exposed populations with vitaltime to flee to higher ground. This may be a matter of minutesto hours, depending on how close they are to an underseaearthquake’s epicentre. 28 Earthquakes and flash floods givelittle or no notice of their onset, meaning that evacuationstake place during or after their initial impact. In contrast, earlywarnings of volcanic activity often allow people to evacuateunder less time pressure, but the exact moment of an eruptionis difficult to predict. This may mean that evacuees aredisplaced for weeks, or that they are allowed to return onlyto be evacuated again at a later date.Periods of heavy seasonal rainfall and riverine and stormrelatedfloods often affect heavily populated low-lying andcoastal areas. As they evolve, they may prompt successivewaves of evacuations over weeks and months, which alsomakes it difficult to distinguish between one disaster and thenext. We identified examples of all these dynamics amongthe displacements reported in 2014, the largest of which inboth absolute and relative terms are discussed in sectionfour.question. The human exploitation andmismanagement of the planet’s naturalresources is an important factor in manydisasters. The decision to dam or divertwater in response to heavy rainfall andflood risk may have immediate impacts ondisplacement, for example. In slowly developingand long-lasting situations, it is lesslikely that a specific hazard can be singledout as the main driver of displacement(see Afghanistan spotlight in section four).Models developed by IDMC and ClimateInteractive also show that the frequencyof drought in the Horn of Africa is a lesssignificant factor in undermining pastoralists’livelihoods and driving their displacementthan other issues, such as changesin government policy. 20 Emphasising thenatural aspect of hazards distracts fromthe role of human activity in the disastersand displacement they cause. 21 As such,an over-emphasis on hazards themselvescan be politically, practically and methodologicallyproblematic.At the same time, anthropogenic climatechange is expected to increasethe intensity and frequency of certainweather-related hazards and the vulnerabilityof some populations as their landand livelihoods become uninhabitable. 22The best scientific knowledge availablemakes clear the urgency of action to bothmitigate global warming and adapt to itshuman impacts, including displacement. 23The complex relationship betweenslow-onset hazards and displacement associatedwith climate change is discussedfurther in box 2.1.Patterns of movementFollowing their initial displacement,people’s trajectories are often complex,a fact seen at both the individualand community level, and within andamong households. It is not unusual fordisplaced people to move a number oftimes, whether in response to threats oropportunities that arise over time as theyseek to end the insecurity and uncertaintyof their displacement and re-establishtheir homes and livelihoods. The abilityto move to where assistance is availablemay indicate resilience. Governments andhumanitarian organisations may relocatepeople from initial shelter sites or evacuationcentres to more secure shelter whenit becomes clearer that displacement islikely to last longer than expected.Movements in response to new threatsto their safety and security in their placesof refuge, however, may constitute secondarydisplacement. Threats may includeexposure to further natural hazardsas a camp becomes flooded, for example,or through exposure to gender-based violenceor forced eviction. Chronic displacement,whether long-lasting, in repeatedcycles or both, undermines people’s resilienceand makes them more vulnerableover time. 2916 Global Estimates 2015