Reconstruction of the rainy season precipitation in central Jordan

Abstract

Concurrent reconstructions of October-April precipitation at Madaba and Rabba gauging sites in central Jordan back to the year 1777 using a multivariate regression model are presented. The reconstruction model was calibrated using concurrent precipitation and tree-ring data for the period 1953-1981 The regression equation is significant (p < 0.05), while reconstructions account for 53% and 48% (adjusted for lost degrees of freedom) of the total variability of the precipitation at the Madaba and Rabba sites, respectively. The validation statistic obtained indicates the existence of worthwhile information in the reconstructions. A threshold of 1 standard deviation below the mean is used to define extremely dry years. The concurrent analysis of the reconstructed precipitation at both sites indicates the occurrence of 24 regional extremely dry periods of between 1 and 2 years' duration. Dry periods of more than 2 years' duration rarely occur. This study indicates the occurrence of noticeable extremely dry individual years: 1800, 1827, 1895 and 1933. The estimated mean recurrence times of extreme droughts are 9.3 and 51.3 years for droughts of 1-year and 2-years duration, respectively.

Estimation of consistent wet period characteristics for further improvement of water resources studies

“…Over the 239 years, the reconstructed precipitation could not copy the magnitude of the largest single year wet event recorded in 1992, which can be explained as a result of two combined factors. The first is attributed to the reconstruction model (regression model) that explained about 53% of the historical precipitation total variability (Tarawneh & Hadadin ). Reconstruction models partial variability explanation was observed in other research (e.g.…”

“…In a previous study (Tarawneh & Hadadin ), the rainy season precipitation for Madaba was reconstructed using the Multivariate Regression model back to the year 1743 benefiting of tree‐ring indices from nearby tree sites (Dana Reserve and Tor Al‐Iraq in Jordan, Ceadar Valley – Trocken and Plano Platres – Feucht in Cyprus). Figure shows the reconstructed rainy season precipitation for Madaba over the period 1743–1981.…”

“…), investigating the occurrence and severity of extreme drought events (Touchan et al . ; Gonzales & Valdes ; Tarawneh & Hadadin ; Woodhouse et al . ; Fang et al .…”

“…As predictor variables, long records of tree-ring indices were used in previous studies to augment short precipitation records (Touchan et al 1999;Yang et al 2014). The extended hydrological or meteorological records were used for several purposes like detecting past climate changes in a particular region (Gou et al 2007;Lara et al 2008;Davi et al 2009;Ge et al 2016), investigating the occurrence and severity of extreme drought events (Touchan et al 1999;Gonzales & Valdes 2003;Tarawneh & Hadadin 2009;Woodhouse et al 2009;Fang et al 2010;Yang et al 2014;Tei et al 2015), detecting the spatiotemporal drought variability and fluctuations (Fang et al 2013;Hou et al 2016). In general, tree-ring reconstructed hydrological records are useful to better manage water resources systems (Elshorbagy et al 2016).…”

Water supply in Jordan under drought conditions

“…Funhermore, droughts of extreme magnitude and short duration lasting 1-3 years were observed by a dendroclimatological study of the region of Southern Jordan, with an average time interval between drought events of 4.2 years (Touchan et al, 1999). Likewise, a joint analysis of reconstructed precipitation at two sites in the central Jordan region showed that regional droughts of short duration (1-3 years) are the most recunent events, with a retum period of about 3.8 years (Tarawneh & Hadadin, 2009). Theoretical models have also been used to investigate the distribution, occurrence probability and retum period of droughts, considering drought length only (e.g.…”