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The early to mid-Holocene has long been recognised as a period of wetter climate with widespread lacustrine development and vegetation expansion throughout south-east Arabia. Recent palaeoclimate data has, however, transformed our understanding of the Holocene Pluvial Phase ( HPP) and evidence presented in this paper demonstrates that climate was neither homogeneous during the period, nor were shifts between pluvial and arid episodes synchronous across the region. This dynamic setting provided the backdrop for human expansion during the Neolithic, and in turn raises important questions about the interactions between these populations and the natural environment in south-east Arabia. [ABSTRACT FROM AUTHOR]

The source and seasonality of rainfall in southern Arabia during the early‐ to mid‐Holocene and preceding humid periods are controversial because fossil lacustrine sediments provide solely indirect information on the amount of rainfall. Hydrogen and oxygen isotope measurements on fluid inclusion water trapped in Holocene and Pleistocene stalagmites from Hoti Cave in Northern Oman are direct indicators of the isotopic composition of paleoprecipitation. Isotope values of fluid inclusions formed during peak interglacial periods plot along monsoonal water lines and are indicative of a southern monsoonal moisture source. The last monsoon‐dominated period lasting from ∼10,100 to 6,300 years before present was terminated within a few decades in southeastern Arabia. The subsequent reduction in rainfall amount and change from predominantly summer to predominantly winter rainfall had a profound impact on human communities living in this area and triggered migration from inland to coastal areas where resources were more abundant. Plain Language Summary: During the Quaternary period, the Arabian Peninsula experienced short intervals of enhanced rainfall, turning the Arabian Desert into a savannah‐type landscape with abundant lakes and wetlands. These intervals are well‐documented in lake sediments and cave deposits throughout Arabia, whereas the source of rainfall is uncertain. Ancient rainwater trapped in fluid inclusions in stalagmites from Hoti Cave, Northern Oman, allows us to determine moisture source changes over the last 350,000 years before present. Using new analytical methods to extract the water from fluid inclusions and measure its hydrogen and oxygen isotopic composition, we are able to show that greatly enhanced rainfall was caused by an intensification and greater northward extension of the African and Indian monsoons into Arabia. For the last humid period between ∼10,500 and 6,300 years before present, stalagmites from Hoti Cave reveal an abrupt termination of the monsoon‐dominated period, a sharp decline in precipitation and change from a summer‐ to winter‐dominated rainfall regime in southeastern Arabia. As a result, human communities were severely affected by this major climatic change and forced to migrate from inland to coastal areas, where water and resources were more abundant. Key Points: Hydrogen and oxygen isotopes in fluid inclusions in stalagmites from Hoti Cave, Northern Oman, reveal changes in the source of rainfallRainfall during the early and middle Holocene originated from the Indian Ocean and was associated with the Indian summer monsoonA change in the seasonality and reduction in rainfall at ∼6,300 years before present had a profound impact on communities in Northern Oman [ABSTRACT FROM AUTHOR]

The PalaeoEnvironments and ARchaeological Landscapes (PEARL) research project is a joint German–British project with the principal objective of developing a framework of past human occupation and landscape change in south‐eastern Arabia. Fieldwork during 2018 and 2019 involved the systematic survey and excavation of sites in the Rustaq and Ibri regions of Northern Oman, with the aim of establishing the nature and timing of human occupation and landscape change during the Early Holocene period (c. 10,000–7,000 years BP). Further to the findings previously reported, results from recent excavations of the site Hayy al‐Sarh in Rustaq revealed the presence of animal remains, stone and shell beads and stone structures, indicating a large Neolithic settlement with burial areas. In addition, preliminary excavations at a rock shelter site near Ibri have revealed stratified archaeological remains, including a Fasad‐type assemblage. Future fieldwork will further develop archaeological and palaeoenvironmental records to help build a framework for studying cultural and natural developments in Northern Oman. [ABSTRACT FROM AUTHOR]