A Role of Remote Sensing Analysis for Archaeological Purposes in Arid Climate Regions

The modern state of Israel is located between 29^o and 33^o north of the Earth’s equator. It is a small (about 22,000 km²) subtropical region between the temperate and tropical zones, characterized chiefly by semi-arid and arid climates. Such climate causes increased productivity and water-use efficiency due to elevated CO₂, which tends to increase ground cover, counteracting the effects of higher temperatures. As a result of this effect, Israel, while small in size, exhibits complex soil formations with variable physical properties, even within small areas. Despite its comparatively diminutive dimensions, Israel has been a focus of human exploitation and settlement since the earliest days of human expansion. More than 27,000 recorded sites form a long record of human presence in the area, starting around 1.5 Mya, presenting one of the densest national archaeological records in the world. While some sites are still clearly visible on the surface, most ancient remains of various ages and origins occur in the subsurface layers at depths of 0.5-8 m (usually in multi-layered archaeological sites). Hundreds, if not thousands, of new sites are discovered yearly due to construction and development activities, and more than 300 salvage excavations are conducted by the Israel Antiquities Authority yearly. Traditional archaeological survey methods are based on covering transects of areas by foot and, while prolific, are by nature highly time-consuming and costly. Moreover, they usually do not supply information on the extent and character of sub-surface remains. Different attempts have been made over the years to apply surface geophysical methods (e.g., GPR, ERT, magnetic, paleomagnetic, subsurface seismics, self-potential, thermal, VLF, induced polarization, piezoelectric, and microgravity) for the identification of archaeological remains as rapid, effective, and noninvasive alternatives for ‘traditional’ archaeological survey methods. However, these attempts have not always been successful, mainly because of the environmental variability and complex physical-archaeological conditions. Remote Sensing (RS) is a low-expensive tool used for detecting and monitoring the physical attributes of objects of interest on or below the Earth’s surface from a considerable distance. RS has been proven instrumental in archaeological investigations and in comprehending historical contexts on a large scale. This is attributed to RS’s rapid data acquisition, expansive coverage, high resolution, and spectral sensitivity to anomalies associated with surface, subsurface, buried, and underwater archaeological features. Archaeologists gain aid in enhanced discoveries and comprehension of archaeological context by utilizing passive and active sensors on drones, satellites, aircraft, and uncrewed aerial vehicles. Active RS (such as radar and LiDAR) offers advantages in detecting buried sites in deserts or concealed archaeological landscapes within forested areas compared to passive RS (encompassing photography and multi-/hyperspectral techniques). The advanced RS application in Israel enabled the unmasking of unknown archaeological targets in the Wadi Asekt (northern Israel) and the Biq’at Sayyarim (southern Israel). Detailed surface geophysical studies (GPR and magnetic) and archaeological investigations will be conducted at the following stage in the selected areas. Information theory approaches and modern wavelet methodologies will be applied to integrate RS data numerically with geophysical (and possibly geochemical) methods.