Migration of Barchan Dunes in Qatar–Controls of the Shamal, Teleconnections, Sea-Level Changes and Human Impact

Abstract

Abstract:Barchan dune fields are a dominant landscape feature in SE Qatar and a key element of the peninsula's geodiversity. The migration of barchan dunes is mainly controlled by dune size, wind patterns, vegetation cover and human impact. We investigate the variability of dune migration in Qatar over a time period of 50 years using high-resolution satellite and aerial imagery. We then explore its relation to the regional Shamal wind system, teleconnection patterns, and limitations in sand supply associated with the transgression of the Arabian Gulf. Strong size-dependent differences in migration rates of individual dunes as well as significant decadal variability on a dune-field scale are detected, which are found to correlate with the intensity of the North Atlantic Oscillation (NAO) and the Indian Summer Monsoon (ISM), in particular during years of relatively strong (weak) summer Shamals. High uncertainties associated with the extrapolation of migration rates back into the Holocene, however, do not permit further examination of the timing of the loss of sand supply and the onset of the mid-Holocene relative sea-level (RSL) highstand. For the youngest phase considered in this study (2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015), human impact has likely accelerated dune migration under a weakening Shamal regime through sand mining and excessive vehicle traffic upwind of the core study area.

Sediment-filled karst depressions and <i>riyad</i> – key archaeological environments of south Qatar

“…The same applies to the northern Arabian palaeolake record from Tayma (Saudi Arabia), which reflects only a very short EHHP and appears offset, probably due to a complex interplay of a range of global and regional atmospheric moisture sources, e.g. the EASM, Mediterranean winter rains and winter-spring tropical plumes (Engel et al, 2012;Enzel et al, 2015;Neugebauer et al, 2018;Parton et al, 2018). Macumber (2018) associates the phase of a wetter climate around the 6th and 5th millennia BCE with the formation of a massive subterraneous freshwater lens over large parts of Qatar.…”

High‐resolution facies analysis of a coastal sabkha in the eastern Gulf of Salwa (Qatar): A spatio‐temporal reconstruction

“…Fryberger et al ., 1988), which has also been observed in the landward part of sabkhas elsewhere in Qatar (Strohmenger & Jameson, 2015) and the karst basin of Asaila close to the Gulf of Salwa coast (Engel et al ., 2020). A gradual reduction of aeolian sand supply and sand movement in the form of barchanoid dunes within the Shamal corridor, which is roughly shore‐parallel at the study site, has to be expected as the transgression had cut off the upwind sand source inside the Bahrain Ridge and the Gulf of Salwa, leading to long‐term deprivation of sand on the entire peninsula (Embabi & Ashour, 1993; Engel et al ., 2018).…”

“…Quartz sand dominates and indicates long‐distance aeolian input by the Shamal at a time when upwind dune fields in the north‐western peninsula still existed (cf. Engel et al ., 2018). The occurrence of similar Facies C2 grainstone in the south (AZ‐W12; Fig.…”

“…3) at a later stage during the late Holocene, when upwind sand sources had ceased (cf. Engel et al ., 2018), is dominated by aragonite, testifying to only local aeolian input from the seaward barrier which, to a large part, consists of skeletal grains.…”

“…The salinity increases towards the southern end (Sugden, 1963), ranging between 50 to 60 psu (Rivers et al ., 2019b), and partially up to 70 psu (Purser & Seibold, 1973; Sheppard et al ., 2010). The dominant regional Shamal wind system operating in a NNW–SSE direction (Rao et al ., 2001; Engel et al ., 2018) drives a moderate southward longshore drift at both sides of the Gulf of Salwa (Chao et al ., 1992).…”