The volcanic eruptions over the past couple years on the island of Ambae in Vanuatu have forced hundreds of residents to evacuate. Through its partnership with Digicel (one of the local mobile network operators) Pulse Lab Jakarta used anonymised mobile network data to generate timely insights for the Government as well as humanitarian agencies. The findings from the research are detailed below.
Ensuring Responsible Use of Data
During and after natural disasters, humanitarian response needs timely information on the distribution of affected people and communities, in particular the geographic locations of displaced populations, to be effective. Throughout the past decade, many research papers have underlined the potential of using mobile network data to strengthen public policy and humanitarian action, yet the full operational potential that exists with the data source is still to be unlocked.
In a recent post, Pulse Lab Jakarta outlined some of the political-economy challenges associated with operationalising mobile network data for sustainable development and humanitarian action. Alongside these challenges, privacy protection is a crucial aspect of every data innovation project developed by the lab. UN Global Pulse applies risk assessment tools for undertaking analysis with new digital data sets as well as privacy and data protection principles. In addition, the Vanuatu project was developed in compliance with the GSM Association privacy guidelines for the use of mobile phone data. Among other principles, the GSMA guidelines dictate that subscriber data be anonymised and that all analysis take place on the mobile network operator’s systems and under the operator’s supervision. Similar to how a statistics office processes census data to produce national statistics, the data science team has analysed anonymised mobile network information to produce statistics relevant to areas of humanitarian action.
Modelling the Effects of Two Natural Disasters in 2017
Before the eruption of Monaro Voui Volcano on Ambae in August 2018, Pulse Lab Jakarta had already been working to model the effects of two natural disasters in Vanuatu: the 2017 Tropical Cyclone Donna and an earlier eruption of the Monaro Voui Volcano on Ambae island in 2017.
The project examined network signals at the cell tower level, conducting wavelet and multifractal analysis. The results indicated that regular patterns exist in the data set, confirming its value as a general source of indicators and insights on outliers that are of use for real-time sensing.
The project then analysed Tropical Cyclone Donna, specifically to understand changes to aggregate behavioural indicators and human mobility networks, finding that the cyclone had clear effects that could be detected in the mobile network data. In the four northern provinces, for instance, aggregate subscriber movements between areas were diminished, and on the strongest day of the cyclone, negative subscriber movement anomalies characterised the areas closest to the eye of the cyclone.
The figures below provide province level and tower level insights on the effects of Tropical Cyclone Donna on human mobility networks:
Next, the project investigated the 2017 eruption of Monaro Voui Volcano on Ambae island, which revealed that mobile network data was useful for understanding the effectiveness of the state of emergency issued by the Government. The figure below represents the proportion of Digicel subscribers who are residents of Ambae (seen in patterns from week 34 and prior) and whether they remained on the island or evacuated during the state of emergency.
The Government made the first evacuation announcement for Ambae residents in week 35, and as seen in the figure above the proportion of mobile network subscribers evacuating from Ambae increased significantly in week 40, compared to previous weeks, which correlates with the Government’s off-island evacuation order, issued at the end of week 39, on 29th September 2017.
Also, Government reports implied that all residents of Ambae were evacuated; but, the mobile network data suggested that a not inconsequential number of residents remained on the island throughout the eruptions and the state of emergency. This is a useful insight for evaluating the effectiveness of public emergency policies.
Timely Operational Insights in 2018
Pulse Lab Jakarta met with representatives from the Government of Vanuatu in mid 2018 to present the findings of the research. The meeting coincided with another episode of active volcanic eruption on Ambae. Having the data and code in place from the previous research, Pulse Lab Jakarta responded to a request from the Office of the Prime Minister for insights on population displacement from the island. The lab provided information on the status of Digicel subscriber evacuations from Ambae as the volcano erupted, as well as aggregate information on evacuation destinations which, alongside data from Government officials, was leveraged to better target assistance and enhance recovery efforts.
*Pulse Lab Jakarta is grateful to Digicel for their continued partnership and looks forward to sharing more aspects and findings from this research partnership over the coming months.