Monitoring Displaced People in Crisis Situations Using Multi-temporal VHR Satellite Data During Humanitarian Operations in South Sudan

Abstract

Natural disasters, changing environmental conditions, and violent regional conflicts are main drivers for population displacement. Worldwide, more than 50 million people are displaced. One tragic example of huge displacement due to a conflict situation is the Republic of South Sudan, where 1.7 million people have been forced to flee their homes since December 2013. Most of them found refuge in numerous spontaneous settlements, either camps for internally displaced people (IDPs) within the country, or refugee camps in neighbouring countries. In such crisis situations, humanitarian organisations often do not have access to the areas and only have vague information on the location and amount of affected population. Using very high resolution (VHR) satellite imagery, rumours about displaced people can be generally verified or falsified, while for areas where displaced people gather, information on amount and spatial distribution of dwellings can be extracted for population estimates. Such information assists in planning services like health care or vaccination campaigns and planning of needed infrastructure like boreholes, latrines or hospitals. Camps in the setup and construction phase are often highly dynamic and require regular monitoring. Beyond this emergency phase, specific information is also requested by organisations involved in camp management in all other phases of humanitarian crisis response, i.e. in the care and maintenance phase, as well as the repatriation phase.

A Multi‐Method Approach to Prioritize Locations of Labor Exploitation for Ground‐Based Interventions

“…2019) or to identify flows of displaced people (Füreder et al. 2015). Although numerous uses of remote sensing in humanitarian operations have been discussed in the literature, there are only a few reports of such applications being used by humanitarian organizations.…”

“…Remote sensing can also save critical resources, because humanitarian organizations can use up‐to‐date data to verify information about the presence of displaced persons (Füreder et al. 2015), even when safety and logistical issues limit access to the field (Lang et al. 2019).…”

Earth observation tools and services to increase the effectiveness of humanitarian assistance

“…Population estimation can be supported by EO data (Bjorgo, 2000;Checchi, Stewart, Palmer, & Grundy, 2013;Giada, de Groeve, & Ehrlich, 2003;Kemper, Jenerowicz, Gueguen, & Poli, 2011;Lang et al, 2010;Tiede, Füreder, Lang, Hölbling, & Zeil, 2013). While using EO data individuals are not directly visible, but indicators of human presence (Ehrlich et al, 2009;Kelly, 1998) such as huts, tents and other infrastructure elements can be detected and the population can be estimated by multiplying each structure by an average structure occupancy rate (Füreder, Lang, Rogenhofer, Tiede, & Papp, 2015). Visual image interpretation, still the most common way of dwelling counting, is generally seen superior to algorithmic approaches in identifying complex features and structures (Checchi et al, 2013).…”

Template matching to support earth observation based refugee camp analysis in obia workflows - creation and evaluation of a dwelling template library for improving dwelling extraction within an object-based framework

“…By the end of 2015, more than 65 million people were forcibly displaced (UNHCR, 2016) caused by natural disasters, changing environmental conditions and violent conflicts, which constitute the main reasons for displacement. Refugee camps and temporary settlements provide refuge for most of these people (Füreder et al, 2015;UNHCR, 2015). Accurate, reliable and up-to-date information about the situation in refugee and IDP camps like population estimations is very important for planning any kind of help like health care, infrastructure or vaccination campaigns.…”