In the 12,000 years preceding the Industrial Revolution, human activities led to significant changes in land cover, plant and animal distributions, surface hydrology, and biochemical cycles. Earth system models suggest that this anthropogenic land cover change influenced regional and global climate. However, the representation of past land use in earth system models is currently oversimplified. As a result, there are large uncertainties in the current understanding of the past and current state of the earth system. In order to improve representation of the variety and scale of impacts that past land use had on the earth system, a global effort is underway to aggregate and synthesize archaeological and historical evidence of land use systems. Here we present a simple, hierarchical classification of land use systems designed to be used with archaeological and historical data at a global scale and a schema of codes that identify land use practices common to a range of systems, both implemented in a geospatial database. The classification scheme and database resulted from an extensive process of consultation with researchers worldwide. Our scheme is designed to deliver consistent, empirically robust data for the improvement of land use models, while simultaneously allowing for a comparative, detailed mapping of land use relevant to the needs of historical scholars. To illustrate the benefits of the classification scheme and methods for mapping historical land use, we apply it to Mesopotamia and Arabia at 6 kya (c. 4000 BCE). The scheme will be used to describe land use by the Past Global Changes (PAGES) LandCover6k working group, an international project comprised of archaeologists, historians, geographers, paleoecologists, and modelers. Beyond this, the scheme has a wide utility for creating a common language between research and policy communities, linking archaeologists with climate modelers, biodiversity conservation workers and initiatives.
Over the past 25 years, CORONA satellite imagery has become an integral part of archaeological research, especially for arid, sparsely vegetated regions such as the Middle East. Since 2020, a new archive of satellite imagery gathered by the US spy satellite programme that succeeded CORONA—HEXAGON—has become widely available for download via the United States Geological Survey. This photographic archive has enormous potential for archaeological research. Here, the authors seek to lower the barriers to accessing and using this imagery by detailing the background, technical specifications and history of the HEXAGON archive. Four case studies illustrate the benefits and limitations of HEXAGON imagery for archaeological and historical research in the Middle East and beyond.
12 March 2019 in Advances in Archaeological Practice
Recently declassified photographs taken by U2 spy planes in the 1950s and 1960s provide an important new source of historical aerial imagery useful for Eurasian archaeology. Like other sources of historical imagery, U2 photos provide a window into the past, before modern agriculture and development destroyed many archaeological sites. U2 imagery is older and in many cases higher resolution than CORONA spy satellite imagery, the other major source of historical imagery for Eurasia, and thus can expand the range of archaeological sites and features that can be studied from an aerial perspective. However, there are significant barriers to finding and retrieving U2 imagery of particular locales, and archaeologists have thus not yet widely used it. In this article, we aim to reduce these barriers by describing the U2 photo dataset and how to access it. We also provide the first spatial index of U2 photos for the Middle East. A brief discussion of archaeological case studies drawn from U2 imagery illustrates its merits and limitations. These case studies include investigations of prehistoric mass-kill hunting traps in eastern Jordan, irrigation systems of the first millennium BC Neo-Assyrian Empire in northern Iraq, and twentieth-century marsh communities in southern Iraq.
New fieldwork at Ur has begun to investigate urban scale, city organization, and the environment of the city's hinterland. Analysis of new sources of declassified aerial and satellite imagery from the 1950s and 1960s, recent unmanned aerial vehicle (UAV) photos, and a systematic surface collection show that Ur may have expanded to between 120–500 hectares in size during its later periods of habitation, far larger than the sixty hectare maximum size previously estimated. Traces of buried architecture visible in the UAV photos and topographic models generated from UAV photos allow for the generation of hypotheses about the city plan of Ur during the Late Larsa/Old Babylonian and Neo Babylonian periods. Relict watercourses mapped in the vicinity of the main mound indicate how the city might have been supplied with water in some periods. Alongside this site-based work, historical aerial and satellite imagery provide an updated picture of ancient hydrology, environment, and settlement patterns around Ur.
Satellite imagery and UAV (drone) photos taken at Lagash (modern Tell al-Hiba) after rainstorms and at times of elevated soil moisture show dense near-surface architecture that dates mostly to the Early Dynastic III period (c. 2600–2350 BCE) and covers several hundred hectares. Archaeological knowledge of Mesopotamian urban structure has mostly been limited to isolated excavated neighbourhoods, such as at third millennium BCE Tutub (Khafajah) or Eshnunna (Tell Asmar), and early second millennium BCE Ur (Tell al-Muqayyar). The morphology of Tell al-Hiba and the quality of the imagery sets create a unique situation that enables the reconstruction and comparison of neighbourhoods across almost the whole of the city of Lagash. Mapping of near-surface architectural remains, streets, and water features reveals a discontinuous city located within a watery, possibly marshy environment.