Heritage Stewardship – Mapping an ancient city with a century of remotely sensed data

Featured Journal Content – Heritage Stewardship

PNAS – Proceedings of the National Academy of Sciences of the United States
of America
[Accessed 2 Jun 2018]
Mapping an ancient city with a century of remotely sensed data
David Stott, Søren Munch Kristiansen, Achim Lichtenberger, and Rubina Raja
PNAS May 29, 2018. 201721509; published ahead of print May 29, 2018. https://doi.org/10.1073/pnas.1721509115
Understanding how people in the past adapted to environmental and economic challenges can help us anticipate and meet these challenges in the present. However, these very processes threaten the physical remains embodying this information worldwide: Urban expansion and resource exploitation mean that the quantity and quality of archaeological information are diminishing daily. In this work, we demonstrate how multitemporal aerial photography and modern airborne laser scanning are invaluable tools for mapping the remaining archaeological features extant in the present and for adding context to them from what has been lost. This knowledge enables cultural heritage administrators and archaeologists to actively monitor, understand, and manage the existing remains to make sure important information is not lost to posterity.
The rapidly growing global population places cultural heritage at great risk, and the encroachment of modern settlement on archaeological sites means that valuable information about how past societies worked and interacted with the environment is lost. To manage and mitigate these risks, we require knowledge about what has been lost and what remains, so we can actively decide what should be investigated and what should be preserved for the future. Remote sensing provides archaeologists with some of the tools we need to do this. In this paper we explore the application of multitemporal, multisensor data to map features and chart the impacts of urban encroachment on the ancient city of Jerash (in modern Jordan) by combining archives of aerial photography dating back to 1917 with state-of-the-art airborne laser scanning. The combined results revealed details of the water distribution system and the ancient city plan. This demonstrates that by combining historical images with modern aerial and ground-based data we can successfully detect and contextualize these features and thus achieve a better understanding of life in a city in the past. These methods are essential, given that much of the ancient city has been lost to modern development and the historical imagery is often our only source of information.