Slavery from Space: A Remote Sensing Approach to Ending Modern Slavery

7 March 2019
Research Innovation

Bethany Jackson  | Research Associate & Fellow in Antislavery Social-Ecological Systems Modelling, the Rights Lab at the University of Nottingham
The Rights Lab  | University of Nottingham Beacon of Excellence

For more than half a century, satellites have been monitoring the Earth’s surface. The remotely sensed data collected by sensors on these satellites have been used to investigate a myriad of features on the planet, from environmental and land cover changes to the development of cities and population growth. The ability to monitor the Earth has developed rapidly in the past 20 years, and this rich history is now frequently applied to work in the field of human rights.

Modern slavery is one of the most pressing human rights issues of our time. It is therefore vital that today’s anti-slavery movement have access to as many tools as possible to both understand and prevent this crime. This includes harnessing available satellite technology to investigate industries, countries and regions where modern slavery practices are commonly reported. Remote sensing can provide evidence to support new forms of advocacy, accountability and action in the effort to prevent slavery and support survivors. In fact, remote sensing technologies are already being implemented to support anti-slavery action.

Mapping Industries

Often the scale of industries is a prohibitive factor to ensuring the elimination of modern slavery within a workforce. This is something that remote sensing can support due to the high spatial and temporal resolution of data collection: with a combination of satellite sources, the entire Earth is mapped every day.

Through the use of freely available satellite sensor data, we produced in the Rights Lab the first statistically robust estimate of the number of brick kilns within the South Asian brick-manufacturing industry. As a highly unregulated industry, the true scale of brick-manufacturing had not previously been quantified. This had made it difficult to determine the exact location of individual kilns across the “Brick Belt”, and to understand which of those kilns are likely to be using slave labour. This data is now being used by NGOs in the region to guide their prioritization of programme locations.

Satellites reveal the telltale shapes of brick kilns in India. © 2019 DIGITALGLOBE, A MAXAR COMPANY

The same technology could be applied to monitor a number of other industries, including quarrying, mining, cotton harvesting, fishing and fish processing. Continued monitoring is possible due to high temporal resolutions from imagery providers such as Planet Labs, a commercial provider, and the European Space Agency (ESA) Sentinel series, a government provider. We are now applying artificial intelligence (AI) algorithms to map and locate new features of interest within these industries, providing an up-to-date log for areas that are sometimes inaccessible or were previously unknown.

Monitoring Vulnerability

The abundance of satellite data means that there is a wealth of information that can be used to monitor vulnerability going forward. The amount of satellite imagery is ever-increasing, but to fully understand the risks of enslavement, we are using this imagery alongside other data such as survivor narratives, population densities, educational attainment levels and poverty rates.

Mining in Peru via Planet Labs.

The ability to monitor patterns on the surface of the Earth will only improve due to the technological innovations taking place on satellite platforms, including improvements to the spatial, spectral and temporal resolutions. Continued investigation of vulnerabilities to modern slavery will require fast responses, and AI will enable the fast processing times that we need to monitor numerous data sources and integrate them with satellite imagery to fully reveal slavery risk and vulnerability.

In addition, the costs associated with the production and operation of spacecraft are continuing to decline with the production of “smallsats” and constellations of satellites, which are beneficial to the timescales in which data are collected. Usually these are operated by commercial providers, but these companies regularly partner with humanitarian and human rights agencies to investigate crises and abuses.

The Nexus of Modern Slavery and Environmental Destruction

Advances in anti-slavery remote sensing also let us combine slavery and environmental data. Assessing the environmental impacts of modern slavery is important for supporting survivors and protecting natural systems. It will help us achieve an intersectional approach to the Sustainable Development Goals.

The history of remote sensing is firmly based in the monitoring of the Earth’s environmental systems. As we document the connection between modern slavery and environmental destruction, we are beginning to use remote sensing sources to investigate these relationships. There are a number of industries where modern slavery has been reported within the workforce and which are known to have an impact on the environment—including quarrying, mining and brick manufacturing. These impacts can include the release of pollutants, deforestation, encroachment on protected areas and the overexploitation of resources, among others.

Satellite imagery has already been used to document cases where gold mining has had drastic effects on the Amazon rainforest environment, causing damage to protected lands. These data sources are also being used to investigate other protected regions. The risks associated with protected areas and vulnerability to enslavement are interlinked due to the remoteness of the locations and the subsequent lack of monitoring. Here satellite imagery can help to protect both people and the environment through land cover mapping and monitoring for instances of change that may indicate human activity, including areas of deforestation, buildings and structures, and the visibility of modes of transport.

Anti-Slavery Futures

Although some forms of modern slavery are not accessible through this technology, such as domestic servitude, remote sensing can support other forms of data collection on the ground. By combining remotely sensed data, other data sources and ground-truthing, we can formulate a picture of slave labour locations and industries in which modern slavery is occurring.

With a wealth of different techniques at hand, including output from satellite sensors, we can enable more evidence-based decision-making. It is this transdisciplinary approach to data collection—working with data sources that would normally be held in silos, and in partnership with NGOs, survivors and government bodies—that will ultimately provide the best insights into modern slavery around the world.

Bethany Jackson is a Geography PhD Candidate (supervised by Doreen Boyd and Kevin Bales) in the Rights Lab at the University of Nottingham. She is currently analysing the Asian brick kiln industry using remotely sensed imagery as part of the Rights Lab’s Data Program. Her work on Slavery from Space combines a geospatial practice that has primarily been used for environmental studies, and demonstrates how a wide variety of satellite images and traditional techniques can also be used to help provide answers to the problem of contemporary slavery. Email:

This article has been prepared by Bethany Jackson as a contributor to Delta 8.7. As provided for in the Terms and Conditions of Use of Delta 8.7, the opinions expressed in this article are those of the author and do not necessarily reflect those of UNU or its partners.

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