Extreme value indicators in highly resolved climate change simulations for the Jordan River area

Abstract

.[1] Understanding changing trends and frequency of extreme rainfall and temperature events is extremely important for optimal planning in many sectors, including agriculture, water resource management, health, and even economics. For people living in the Jordan River region of the Middle East such changes can have immediate devastating impacts as water resources are already scarce and overexploited and summer temperatures in the desert regions can reach 45°C or higher. Understanding shifts in frequency and intensity of extreme events can provide crucial information for planning and adaptation. In this paper we present results from regional climate model simulations with RegCM3 and MM5 centered on the eastern Mediterranean region. Our analysis focuses on changes in extreme temperature and rainfall events. We show that maximum daily summer temperature is expected to increase by between 2.5°C and 3°C, with an increase in warm spell length. Precipitation extremes are expected to increase with longer dry spells, shorter wet spells, and increases in heavy rainfall. Model agreement for the control period 1961-1990 is higher in the southern region than in the north, perhaps because of the complex topography, suggesting that even small differences in spatial scale play an important role. In addition, we notice that the chosen global model plays an important role in determining future temperature trends, while the choice of regional climate model is critical for understanding how precipitation is expected to evolve.

Addressing drought conditions under current and future climates in the Jordan River region

“…By 2031-2060, an increase of temperature by 1.5-2.0 • C is simulated; the highest increase is simulated by HadCM3-MM5 followed by ECHAM5-RegCM3 and ECHAM5-MM5, respectively. As also noticed by Samuels et al (2011), all models show a higher temperature increase inland than at the coast. The authors suggest that it could be related to cooling effects of sea breezes.…”

“…The performance of these climate projections for the current conditions has been evaluated by Samuels et al (2011). The authors compared the output of the climate models with the same gridded data set on observed precipitation that was applied in the present study.…”

“…Krichak et al (2011) applied an ECHAM5/MPI-OM RegCM3 model and noticed a significant trend of decreasing winter precipitation in near-coastal areas and an increasing trend in air temperature for all seasons. Samuels et al (2011) applied the ECHAM5 and HadCM3 GCMs in combination with the RegCM3 and MM5 RCMs. Their results showed that the maximum daily temperature is expected to increase by 2.5-3 • C and that the lengths of warm and dry spells are expected to be prolonged by 2021-2050 compared with the control period of 1961-1990 applied the ECHAM-MM5 and HADCM3-MM5 projections and identified a 2.1 • C mean increase of the annual mean temperature by 2031-2060 compared with 1961-1990.…”

Recharge estimation and soil moisture dynamics in a Mediterranean, semi-arid karst region

“…The use of empirical rainfall-recharge relationships can lead to large errors, since recharge rates are sensitive with respect to highly variable rainfall distributions and characteristics, which are most probably affected by predicted climate change in the Mediterranean (Giorgi and Lionello, 2008;Samuels et al, 2011;Reiser and Kutiel, 2012).…”

Comparing One-Way and Two-Way Coupled Hydrometeorological Forecasting Systems for Flood Forecasting in the Mediterranean Region

“…Additionally, it is widely expected that climate change will increase the frequency of severe rain events in many regions around the world (Milly et al 2001 [2]; Wagener et al 2010 [3]; Kundzewicz et al 2010 [4]; Trenberth, 2011 [5]; Zwiers et al 2013 [6]; Andersen et al 2013 [7]). In the Mediterranean basin, these effects could lead to increasing droughts on one hand (Törnros and Menzel, 2014 [8]; Hoerling et al 2012 [9]; Dai, 2011 [10]; Smiatek et al 2011 [11]; 2013 [12]; 2014 [13]) and intensified flood events on the other (Yosef et al 2009 [14]; Samuels et al 2011 [15]). Land use changes and increasing urbanization are also factors that may enhance flood intensity and frequency (e.g., Bronstert et al 2002 [16]; Chang et al 2008 [17]; Githui et al 2010 [18]; Delgado et al 2010 [19]; Kalantari, 2014 [20].…”