Annual mean distributions of PM2.5 over the EMME, derived from

centuries (Xoplaki et al., 2001). All proxies and their adjacent areas, except the lakes Neor and Nar, experienced strong variability and a clear drying trend. It is worth noting that the Neor Lake record presents the last major atmospheric dust event as late as in the 1930s, while the Nar Lake’s humid 20th century corresponds to a combination of the influence of the Indian monsoon and the North Atlantic Oscillation over the area.

3.2. Recent changes

3.2.1. Temperature

Following the global trend, observed regional changes in climate parameters over the past 120 years are characterised by pronounced warming (Figure 8, top panel). There is unequivocal evidence that this is related to anthropogenic activities and elevated concentrations of GHG gases in the atmosphere (IPCC, 2013). This warming accelerated over the past four decades to reach about 1.4-1.5°C compared to the beginning of the 20th century (Figure 8, top panel). For example, during the past three decades, the surface temperature of the Sahara Desert increased at a rate two to four times greater than that of the tropical-mean temperature (Cook and Vizy, 2015). This recent acceleration in regional warming is tracked by several studies, based on various observational data sources (Christensen et al., 2013; Zittis and Hadjinicolaou, 2017; Cramer et al., 2018; Lionello and Scarascia, 2018). Because of various global, regional or local meteorological processes and feedbacks (e.g. modes of internal climate variability, land-atmosphere and land-sea interactions, urbanisation and other land-use changes), the sign, magnitude and significance level of observed temperature trends vary. These can depend on 1) location and geographical characteristics, 2) the type of dataset investigated, 3) the season under consideration and 4) the period of analysis. Nevertheless, significant positive trends of the order of 0.1-0.6°C/ decade have been identified for most EMME territories, including Egypt, Turkey, Greece, Israel, Jordan, Lebanon, the Arabian Peninsula and more (Feidas et al., 2007; Freiwan and Kadioǧlu, 2008; Shohami et al., 2011; Tanarhte et al., 2012; Ramadan et al., 2013; Almazroui et al., 2014; Donat et al., 2014; Mariotti et al., 2015; Xoplaki et al., 2016; Mostafa et al., 2019; El Kenawy et al., 2019; Mohammed and Fallah, 2019; Almazroui, 2020a).

Our updated analysis reveals an indicative EMME region-average trend of 0.45°C/decade for 1981-2019, which is nearly twice the global trend for the same period (0.27°C/decade) (Figure 8, top panel). These values are based on the latest version of the Climate Research Unit dataset (CRU-TS4.04) of the University of East Anglia (Harris et al., 2020). Considering the dataset’s entire time frame of 1901-2019, the global and regional temperature trends are similar (0.11°C/decade). When regional warming in the EMME is compared with other parts of the world, including Europe, the United States, Africa, South America and