Earthquakes
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Maps produced during a humanitarian response to floods (including those caused by tropical storm events), focusing on the hazards and impacts that typically characterise such emergencies. Floods may affect wide areas, limiting access to communities and triggering large-scale population displacement. Maps in association with satellite imaging can visualise the extent of flooding and analyse the likely impact on communities. They are also used to plan needs assessments and a humanitarian response across multiple sectors.
Both.
Situational.
Usually early on in the response, to provide initial predictive or actual impact information that can then highlight priority areas for a life-saving response, and to focus in-field damage and needs assessment on areas most likely to be affected.
All responders, but particularly those operating across the wider affected area, and including those working on assessment processes and response planning and coordination.
Floods may be localised, but can also cover wide areas and render communities inaccessible. Initial response decisions including resource mobilisation should be taken in light of what can be inferred from remote sensing of the extent of the floods. However, such predictors should be used with caution, recognising that the reach of floods may continue to change rapidly, and should be triangulated as soon as possible with mapping of primary data such as field assessment reports.
Keep in mind that floodwater is not static and that maps should therefore be updated regularly.
Attempts to model predicted flooding using, for example, elevation contours, are unlikely to be reliable and should be avoided unless there is a proven methodology.
Prolonged water logging of ground, which may not show up as standing water on imagery, can have a severe humanitarian impact – so reliance on remote sensing alone should be avoided. Large 3W datasets can be mapped using Data Driven Pages (ESRI) or QGIS Atlas.
Remote sensed data from satellite imaging data providers such as UNOSAT. This should be requested as pre-analysed vector data (e.g. ‘flood polygons’) rather than raw imagery. Caution must however be used with such data, due to the unknown effectiveness of analysis.
Any available data from previous flood events may be helpful in identifying areas prone to flooding, although obviously such data should be interpreted with caution in the current situation.
Flood forecasting and modelling maps aim to show where there is a risk of flooding in an area based using precipitation, streamflow data and a range of other criteria. The time range and accuracy varies according to the models. You will see flood modelling predicting the flood extents as rain is falling or based on probability i.e. a 100 year flood event.
Both.
Baseline.
The maps that look at probability will be part of preparedness work done by the science and engineering communities as part of preparedness and insurance work. The short term forecasting will occur as the event unfolds.
All responders, but particularly those operating across the wider affected area, and including those working on assessment processes and response planning and coordination.
For governments planning responses the maps will be indicative of the risk and exposure to floods in specific areas allowing them to plan construction work to mitigate and also to give them an indication how much of a population might need evacuting or some form of assistance in the event of a flood.
The actual modelling of a flood is complex and requires a range of data which is unlikely to be found in the middle of a response. Beacuase of this it is better to look towards those organisations that create the models. In a response, or part of preparedness work additional datasets, such as population and infrastructure could be included to show who and what could be affected by a flood.
Predicted flood events
Geological hazards include events such earthquakes, landslides and volcanos and there are a range of maps and products that can be produced before and after the event or events. Often when there is one event there may be secondary hazards and events. For example, after an earthquake there may be aftershocks, a tsunami, liquefaction or landslides.
These are maps that may be produced in response to a particular hazard (e.g. earthquake, flood, storm, conflict, etc.). They should be supported by the core maps.
Click through on each map to explore how they might be useful.
These are maps depicting the hazards and impacts of landslides or other mass movements such as snow avalanches.
Usually operational.
Situational.
When landslides pose the main or a secondary humanitarian hazard, particularly in association with earthquakes or storm events (particularly after very heavy rainfall). Maps may be produced to identify areas vulnerable to landslides in order to identify at risk communities, or to prioritise on-the-ground or aerial damage assessments. Landslides may also be mapped to identify barriers to access to disaster-affected areas.
All responders, but particularly those working on assessment processes and response planning and coordination. Also, when relevant, logistics planning actors.
Landslides can have a direct impact on communities, and can also block access to large areas of land. Maps showing known/confirmed landslides may be valuable as proxy indicators of likely damage and needs after an earthquake or storm event. Predictive mapping should be used only with caution.
Predictive mapping of landslides may use spatial variables such as earthquake shake intensity, slope angles and cumulative rainfall statistics.
Data on actual landslides can be reliably obtained from ground level, aerial or satellite remote sensing. If these are included on maps, then any areas not analysed should be clearly identified to avoid "no data = no impact" confusions.
In the case of earthquakes: modelled shake intensity (as polygons).
In the case of storms events: cumulative rainfall data – typically from national or regional meteorological agencies.
Terrain data allowing analysis of average slope angles.
Reported landslide locations (points or polygons) derived from ground survey, aerial or satellite imagery.
Maps produced to support clearance or other risk mitigation from unexploded ordnance or other explosive remnants of war. This may be due to generalised contamination of an area post-conflict or as a result of a specific explosive accident or deliberate act.
Operational.
Situational.
When there is a risk from unexploded ordnance with a potential humanitarian impact. This may be when humanitarian operations are being undertaken in an area affected by explosive remnants of war, or in the aftermath of a serious accident that may have caused dispersal of dangerous materials. Maps will invariably be produced under guidance from specialist agencies such as demining organisations.
Organisations involved in making an area safe, and humanitarian actors who need to work in an area believed to be affected by unexploded ordnance or other dangerous materials.
In addition to serving as an information tool for clearance operations, maps may also be important for clarifying which areas are deemed safe, thereby allowing aid agencies to operate.
Mapping will generally define zones/areas based on assessed hazards, and may split areas into sectors for technical and non-technical search operations. Such sectioning should normally be based on identifiable features on the ground, unless technical experts request otherwise.
Maps depicting military locations, even former ones, should be created and circulated with due regard to possible government and military sensitivities, which should be discussed with humanitarian coordination actors before publishing any maps.
Topographic mapping at large scale to identify terrain features. In urban areas, building footprints (e.g. OpenStreetMap data) may be of high importance.
Data on areas likely to pose high risks of contamination from explosive remnants of war, for example bridges, route choke points and former military defensive positions. Such data should be collected and used with due regard to sensitivities.
Operational sector and zone perimeter definitions provided by appropriately qualified specialist agencies.
Maps produced in response to a disease outbreak or epidemic, depicting the incidence and spread of the disease, public health countermeasures, or both.
Both
Situational.
Mapping may be in demand at all stages of a disease outbreak.
All responders including health sector actors, but also other humanitarian responders including logistics, nutrition and other sectors.
Major disease outbreaks involving an international response are rare, however in such cases mapping may be an important tool for understanding the spatial progression of the infection, and for planning and coordinating health services for disease control and treatment, as well as addressing wider humanitarian needs arising due to the outbreak.
Disease characteristics vary (as shown in the 2014-15 Ebola outbreak), and so the spread of even a previously well-understood disease in a new context may be novel.
Epidemiologists may aspire to map outbreak data at a very granular level; however this should not be allowed to delay or compromise mapping of more generalised data (e.g. total number of cases at district level).
Effective management of the outbreak will depend on timely updates of case data and control measures. Standardised maps/infographics must therefore be capable of being rapidly updated and disseminated.
Maps of case incidence should show clearly the change in case rates – take advice from epidemiologists about intervals and other metrics.
Baselines: population data; pre-outbreak health indicators (although these will not normally be spatially discriminated); public water supply infrastructure (in the case of cholera or other waterborne diseases).
Case data for current and any previous outbreaks.
Healthcare infrastructure (usually collated by the Ministry of Health or health cluster).
Maps produced during a humanitarian response to earthquakes, visualising the seismic data and any data that may forecast the extent of physical damage and potentially act as a proxy for humanitarian impact. It may be combined with other thematic layers, notably with baseline population data to enable a rapid/early analysis of the population potentially affected.
Both
Situational.
At an early stage after the occurrence of a major earthquake with the potential to create damage and casualties. The necessary data will invariably be available within hours of the initial earthquake. Data and maps may be updated following aftershocks or to add additional analysis layers, including for example assessed landslide risk zones, vulnerable infrastructure (e.g. dams), or population baselines.
All responders, but particularly those operating across the wider affected area and including actors working on assessment processes and response planning and coordination.
The map will provide context to the potential scope and scale of earthquake. It shows them the location of the epicentre (and aftershocks) and the intensity in different areas. When this is shown with population data it will also give an indication of potentially where the most affected people will be. It will inform them of where potential search and rescue activity might be required.
Initial data, typically from United States Geological Survey (USGS) Earthquake alerts, will give basic indicators including the magnitude and location of the epicentre of the initial event and any aftershocks. This point data should be placed on the map first. It is not good practice to buffer circular rings around the epicentre as this may imply a spatially regular fall-off of damage which is very unlikely to reflect reality. As a large earthquake is “more appropriately described as a slip over a larger fault area” (USGS, see below), single points are poor representations of large earthquakes, so a map showing zones of ‘shake intensity’ provides more useful information. Analysed shake intensity zone data should be obtained mapped as soon as possible. Because this is modelled predictively rather and not ground truthed, it should be appropriately explained and have a caveat on maps. A suitable base map will normally include terrain and any available data on population distribution or population places.
Geophysical data is usually obtained from United States Geological Survey or others. This may include locations of reported epicentres of primary and aftershocks (as points), and modelled shake intensity (as polygons).
Data on predicted or actual landslides from various providers; but be cautious of the methods used to derive these as they may not be reliable.
Analysed satellite imagery to identify building damage; but be cautious because analysis methods may not have been standardised or reliable, and take special care to identify areas that have not been analysed.
Maps to support the process and outputs of an environmental assessment undertaken in the context of a humanitarian emergency.
Both.
Situational.
Rapid environmental assessments may be undertaken as part of the response to a potential or actual release of a pollutant that could cause large-scale human impact. This may be due to a specific technological/industrial accident, or where an elevated hazard is assumed due to a natural disaster such as a flood or earthquake. Such assessments may be coordinated by the Joint United Nations Environment Programme (UNEP)/OCHA Environment Unit.
While maps may be produced for specific technical users, maps will more generally be required for non- technical audiences, including humanitarian agencies and the potentially affected population themselves.
The identification of a potential threat from environmental pollutants may in certain cases be serious enough to drive decisions about the evacuation of vulnerable populations. In very severe situations such as the release of highly toxic materials, mapping may also be needed to enable responding agencies to operate safely.
Assessment outputs to be mapped will typically include potential or actual sources of pollution, and sensitive ‘receptors’ such as communities, water sources or agricultural assets.
Be cautious about inferring any predictive models of pollutant transport and dispersal; however it may certainly be relevant and useful to include generalised annotations such as river flow and prevailing wind directions.
Relevant baseline data of potential ‘receptors’ including populations, agriculture.
Watercourses and water bodies.
Locations of potentially polluting features such as industrial facilities, chemical storage sites etc
Where groundwater pollution may be involved: geological mapping and, if available, aquifers.
Landuse data such as as Modis or GlobCover.
Maps relating to volcanic activity may show pre-existing lava and pyroclastic flows, vents and craters. They may also show other associated hazards such as new lava flows, volcanic gas, lahars, jökulhlaups and pyroclastic flows. Decision-makers will be looking to identify possible evacuation routes from these maps.
Both
Basemap and situational.
Pre-existing geological maps may already exist and these can be used early on. As the situational data arrives it is important that the maps are updated. This is particularly the case where volcanic gas and ash clouds are present and there is wind and rain in the area, which will influence which direction the ash will carry and how much is in the air.
Civil defence and anyone involved with evacuation.
Decision-makers are going to be interested in identifying evacuation routes and safe zones. Basemaps may show pre-existing lava and pyroclastic flows, vents and craters. Volcanic hazards that may need to be mapped or may influence decision-making include:
Lava flows: molten rock that is expelled during a volcanic eruption and moves downhill.
Volcanic gas: this will be released by a volcano typically as water vapour, but also as carbon dioxide, carbon monoxide, sulphur oxides, hydrogen sulfide, chlorine and fluorine. Most of the time volcanic gases are noxious, but they can cause mass fatalities.
Lahars: these are particular types of mud flows containing a mixture of pyroclastic materials, rocky debris and water. These can occur as a result of heavy rainfall, the rapid draining of a crater lake or melting ice. These flows can be highly damaging. When the flows stop they can become as solid as concrete.
Jökulhlaups: this is a kind of glacial outburst flood associated with geothermal activity under a glacier.
Pyroclastic flows: a fast moving current of hot gas and rock that flows down and away from the volcano.
Create distance buffers around the volcano. These can then be used to identify villages and communities possibly within reach of gas and ash clouds. Distance products depicting the spread of gas and ash can be produced by using wind direction and speed.
Geological mapping showing vents and other hazards.
Ash and gas cloud.
Wind direction and speed.
Liquefaction will typically (but not exclusively) occur as a result of an earthquake and can cause significant destruction. Maps on liquefaction may show either areas at risk to it through complex modelling or post event areas and the damage caused by liquefaction.
Both
Baseline and situational.
Liquefaction modelling will occur before the event as a preparedness activity by a government, scientific or engineering organisation. Post event, mapping may happen as a result of field assessments or remote sensing analysis.
Anyone involved with planning will be interested in modelling maps and those involved with response will be interested in post disaster mapping.
Modelled maps will be used by planners and officials to understand the areas and populations that may be exposed and prone to liquefaction. If in the event of liquefaction responders, particularly the urban search and rescue teams, will be wanting to understand where liquefaction has occurred so that they can facilitate any rescues.
liquefaction modelling is a complex methodology and will required a range of datasets including rock and soil type, hydrology, buildings and seismological. Post disaster mapping should show the extent of the liquefaction, any damage to buildings and general infrastructure and also the population that has been affected. Satellite and aerial photography can be used to identify those areas, as well as field assessments.
Modelled liquefaction exposure
Pre and post disaster imagery to compare the areas before and after
Building and landuse
Population
Infrastructure
During many emergency responses weather will play some role, either as the trigger event e.g. a cyclone, heavy rain, extreme temperature (hot or cold), or to inform responders for longer term planning such as winterisation.
Both.
Situational.
If the response has been triggered due to a weather event then immediately, and these should then be updated once a day, particularly for floods where rainfall will have an impact. For longer term planning, creating products with monthly averages can be done well in advance.
Almost all responders, particularly urban search and rescue teams, pilots, logisticians and those involved with winterisation.
The weather will have a series of different effects for different users. For search and rescue teams and pilots, poor weather (high precipitation, cloud cover or wind) may hamper their ability to operate. Heavy rainfall may make roads impassable, hampering the work of logisticians trying to move aid using trucks. The lack of rainfall or extreme temperatures may impact on agriculture, making it difficult for crops to grow. The weather will also determine the type of shelter that is used in camps or temporary shelters, i.e. is there a need to provide shelter from extreme temperatures, heavy rain, snowfall, etc. Conversely there may be improvements in a response. A reduction in rain during flooding will put less strain on river systems that are close to or over capacity. It will also help improve road conditions. In areas of drought, rainfall will begin to help improve conditions by providing water that is much-needed. A rise in temperatures during cold weather events will put less strain on fuel for keeping warm, etc.
For cyclones and flooding produce maps showing rainfall and storm paths, including wind strength. These should be produced daily and updated as required.
For long-term planning produce monthly snapshots showing maximum and minimum temperatures and precipitation.
For a time series of products consider the scale and how it should be classified across the full time period. Look at the maximum and minimum extents of the range and use these for each period. Once the scale and classification have been calculated, use the same colour ramp in the symbology. Doing so makes it easier for the user to compare each month.
In the event of a cyclone or storm there is a threat of a storm surge and coastal flooding along coastal areas. It is affected my a number of factors including the depth (shallowness) of the water, land masses funnelling the water through a smaller gap and the tides. A storm surge on a high tide will have a higher impact.
Both.
Situational.
Modelling may have already been done as a preparedness activity by the national meteorological service and if available the data can be used in conjunction with the storm track as soon as possible.
All responders, but particularly those operating across the wider affected area, and including actors working on assessment processes and response planning and coordination.
With 40% of the global population living in coastal regions, storm surges can have a high impact on the population and properties. The map will help the decision makers understand what populations are exposed to the risk of a storm surge and take the necessary actions such as evacuating the population.
The storm surge data before the event will be modelled and will be indicative i.e. a surge might not occur at that specific location for that event. Post event there will be either recorded data from measuring stations, field assessments or remote sensing.
In the case of modelled data, a series of maps may need to be produced based on the different modelled storm surge heights. For post disaster maps, tt will be possible to indicate which areas have been affected from post disaster analysis. As with many of the storm related maps using the storm track is a useful indicator.
The following data types may be available from national or regional meteorological agencies:
Storm tracks: forecast and actual
Storm surge modelling
Storm surge observations
Storm surge remote sensing observations
Maps produced during a humanitarian response to storm events – typically tropical storms – focusing on the hazards and impacts that typically characterise such emergencies.
Both.
Situational.
Usually early on in the response, to provide initial predictive or actual impact information that can then highlight priorities for life-saving responses, and focus in-field damage and needs assessment on areas most likely to be affected.
All responders, but particularly those operating across the wider affected area, and including actors working on assessment processes and response planning and coordination.
Storm events may have multiple aspects of damage and impact, including the direct effects of high winds, rainfall and consequent flooding, storm surges and coastal flooding. Storms often affect large areas and compromise telecommunications. Therefore, predictors of physical damage and impact may be important for both the initial response and assessment planning. However, such predictors should be used with caution and should be triangulated as soon as possible with mapping of primary data such as field assessment reports.
Take care when labelling and annotating maps to distinguish between forecast, modelled and actual observations. Make sure to avoid confusion over both the date and time the forecast was issued, and the date and time to which the forecast applies. Caution should also be taken when showing the cone of uncertainty - this where the storm could go and not necessarily the whole area that will be affected or damaged.
The following data types may be available from national or regional meteorological agencies:
Storm tracks: forecast and actual
Storm surge data for selected coastal locations.
Accumulated rainfall for selected locations, or ideally as polygons
The wind speed probability maps is complimentary to any storm track map that may be produced. It provides an indication of expected wind speeds along the path of the storm.
Both.
Situational.
Before the cyclone or storm has made landfall. It will help with the planning of a response as it will indicate where the strongest winds are expected and therefore the areas that might be more prone to damage.
All responders, but particularly those operating across the wider affected area, and including actors working on assessment processes and response planning and coordination.
Storm events may have multiple aspects of damage and impact, including the direct effects of high winds, rainfall and consequent flooding, storm surges and coastal flooding.
Include the actual and forecasted storm track. The data often comes at three wind speeds and it is very easy to produce a map with a map frame for each of the wind speeds. Take care when labelling and annotating maps to distinguish between forecast, modelled and actual observations. Make sure to avoid confusion over both the date and time the forecast was issued, and the date and time to which the forecast applies.
The following data types may be available from national or regional meteorological agencies:
Storm tracks: forecast and actual
Wind speed probabilities
Daily rainfall:
Monthly averages:
Maps to assist in the planning for humanitarian responses that are expected to continue into the winter season. They help responders to plan for humanitarian responses under cold weather conditions, by identifying communities facilitate timely response to earthquake disasters, focusing on anticipated hazards and impacts of this type of event. Maps may be produced to coordinate urban search and rescue, to visualise access to affected areas, to analyse patterns of structural damage and assessed needs, and to plan a humanitarian response across multiple sectors.
Both.
Situational.
Disasters or complex emergencies may occur during wintertime, or humanitarian needs may be anticipated to continue into the cold season. Maps to assist in ‘winterisation’ may therefore be requested at an early stage of an emergency, well ahead of the onset of cold weather.
Humanitarian responders, particularly emergency shelter and camp coordination and management actors.
When population displacement has occurred or is threatened, the provision of climate-appropriate assistance is essential to avoid harm to vulnerable populations. It is particularly important to provide winterised shelter and also to reliably anticipate and plan for logistical access for relief assistance during winter months. Maps are essential for the spatial planning of winter relief operations.
If no historical temperature data is available, use elevation data as a proxy and annotate estimated winter low temperatures based on the lapse rate (approximately 6 degrees C per 1,000 metres elevation).
Overlay locations of vulnerable people, e.g. IDP camps, to highlight where winterisation programming is most likely to be a priority.
Topographic data with vectorised elevation to allow upland areas to be symbolised appropriately.
If available, historical average winter low temperature data and, if relevant, rainfall/snowfall data. This may be available from national or regional meteorological agencies.
Any data available on access to key routes during winter conditions.
Maps produced during a humanitarian response to destructive tsunami, usually arising from offshore earthquakes. This section describes mapping the specific impacts of the tsunami, rather than the trigger earthquake, which may itself have direct effects on land.
Both
Situational.
Usually early on in the response, to map impact information that can then highlight priorities for a life-saving response, and to focus in-field damage and needs assessment on areas most likely to be affected.
All responders, but particularly those operating across the wider affected area, including actors working on assessment processes and response planning and coordination, and on logistics planning.
Tsunamis cause humanitarian impacts through their direct effects (coastal flooding with little or no warning), and indirectly they may hamper a response to the wider impacts of an earthquake, for example by impeding access. Any impact close to the coast is likely to be devastating, and create multi-faceted needs in densely populated coastal zones. Where primary transport links have been severed, e.g. coastal roads, mapping is likely to be an important tool for planning and coordinating logistical access to affected communities.
While the extent of inundation will vary along a coast hit by a tsunami, it can be assumed that communities close to the coast, even if not flooded, will see affected people seeking refuge. Therefore, mapping of communities, with population figures of those living within the coastal zone will be valuable for needs assessment.
The following data types may be available from national or regional meteorological agencies:
Modelled data on tsunami propagation, if available. However, be aware that local variations in coastal morphology will greatly vary the wave impact location by location.
Settlement data for coastal districts.
Road data, including if possible locations of bridges over coastal inlets.
Search and rescue maps are often produced during a humanitarian response to earthquakes, focusing on the hazards and impacts that typically characterise these emergencies. They should facilitate a timely response to earthquake disasters, focusing on anticipated hazards such as aftershocks, and the impacts of this type of event. Maps may be produced to coordinate urban search and rescue (USAR) efforts, to visualise access to affected areas, to analyse patterns of structural damage and assessed needs, or to plan a humanitarian response across multiple sectors.
Both
Situational.
Usually early on in the response, to provide initial predictive or actual impact information that can then highlight priorities for life-saving responses including urban search and rescue, and to focus in-field damage and needs assessment on areas most likely to be affected.
All responders, but particularly those operating across the wider affected area, and including actors working on assessment processes and response planning and coordination.
Earthquakes often affect very wide areas, much of which may be rendered inaccessible by the disaster. Initial response decisions including resource mobilisation should be taken in light of what can be inferred from predictors of physical damage, including geophysical mapping. However, such predictors should be used with caution, and should be triangulated as soon as possible with mapping of primary data such as field assessment reports.
Operationally, search and rescue teams require rapid detailed maps of collapsed site locations and search sector boundaries, as well as hospital locations and status, base of operations and other resources.
It is important to get street level mapping produced as early as possible, and the inclusion of satellite or aerial imagery may also help responders identify key features on the ground.
When producing a sector map use linear features that are easily identifiable on the ground post- earthquake, such as broad roads or rivers. Maps should include building outlines where possible or give an indication of building and population density. The greater the density the smaller the sectors should be, as these will most likely take the longest to search. Initial sectors may be quite large to begin with, but smaller sub-sectors may be created. Each sector or sub-sector should be given a unique ID so that rescue teams can identify them more easily. Maps should include a table showing the sector’s ID, the team that is working the area, and the team type (heavy, medium or light).
Roads
Building Type
Place names
Points of Interest
Hospitals
Analysed satellite imagery to identify building damage; but be cautious because analysis methods may not have been standardised or reliable, and take special care to identify areas that have not been analysed.
There are a number of different maps that can be created as part of a response to an armed conflict or other situations of violence.
These are products that are produced in response to armed conflict or other situations of violence such as political unrest. A humanitarian response in this situation is likely to be multi-faceted, and so as many specific map types may be equally applicable in complex emergencies as in natural disasters. There is likely to be particular considerations given to mapping humanitarian access and protection issues, and to tracking recurring phases of displacement and return.
Both.
Situational.
Products may be in demand at all stages. Crises including conflict or violence may be protracted and exhibit multiple stages of impact on affected populations.
All humanitarian responders.
As with natural disasters, maps are important for multiple aspects of humanitarian responses to armed conflict and violence, including situational appreciation, needs assessment, mobilising resources, inter- agency coordination, safety and security of aid personnel, and monitoring of the response.
All data processing and mapping in complex emergencies must give full regard to potential protection issues through disclosure of the whereabouts of vulnerable populations, and of the risks to aid agencies from any misconstrued motives around humanitarian mapping.
The chief driver of humanitarian need in complex emergencies is often displacement. Tracking displaced populations and their needs is therefore often a priority.
Humanitarian access to affected communities and displaced groups may be limited, and mapping should support the maintenance and use of such access that does exist. This may mean that map circulation needs to be restricted to screened groups of users.
Basemap, baseline and situational data needs are not fundamentally different from those of a natural disaster, however special care may need to be taken when processing and using data on vulnerable populations to ensure they are not put at greater risk.
