Seasonal ecosystem vulnerability to climatic anomalies in the Mediterranean

Abstract

Abstract. Mediterranean ecosystems are particularly vulnerable to climate change and the associated increase in climate anomalies. This study investigates extreme ecosystem responses evoked by climatic drivers in the Mediterranean Basin for the time span 1999–2019 with a specific focus on seasonal variations as the seasonal timing of climatic anomalies is considered essential for impact and vulnerability assessment. A bivariate vulnerability analysis is performed for each month of the year to quantify which combinations of the drivers temperature (obtained from ERA5-Land) and soil moisture (obtained from ESA CCI and ERA5-Land) lead to extreme reductions in ecosystem productivity using the fraction of absorbed photosynthetically active radiation (FAPAR; obtained from the Copernicus Global Land Service) as a proxy. The bivariate analysis clearly showed that, in many cases, it is not just one but a combination of both drivers that causes ecosystem vulnerability. The overall pattern shows that Mediterranean ecosystems are prone to three soil moisture regimes during the yearly cycle: they are vulnerable to hot and dry conditions from May to July, to cold and dry conditions from August to October, and to cold conditions from November to April, illustrating the shift from a soil-moisture-limited regime in summer to an energy-limited regime in winter. In late spring, a month with significant vulnerability to hot conditions only often precedes the next stage of vulnerability to both hot and dry conditions, suggesting that high temperatures lead to critically low soil moisture levels with a certain time lag. In the eastern Mediterranean, the period of vulnerability to hot and dry conditions within the year is much longer than in the western Mediterranean. Our results show that it is crucial to account for both spatial and temporal variability to adequately assess ecosystem vulnerability. The seasonal vulnerability approach presented in this study helps to provide detailed insights regarding the specific phenological stage of the year in which ecosystem vulnerability to a certain climatic condition occurs.

The role of soil temperature in mediterranean vineyards in a climate change context

“…The Mediterranean region has a warm season transitional climate, in which evapotranspiration is limited by low soil moisture rather than by solar radiation ( Feng et al., 2022 ). In this context, low soil moisture will amplify heat anomalies and extremes in the region ( Seneviratne et al., 2010 ; Vogel et al., 2021 ; Feng et al., 2022 ) with a potential major impact on growth and yield of both crop and weed species.…”

Spatiotemporal investigation of wet–cold compound events in Greece

“…The motivation for this is the absence of studies that examine extreme wet-cold compound events (WCCEs) in Greece, although Greece as part of the Mediterranean is considered a region affected by WCCEs (Zhang et al, 2021). Similar studies have been conducted for the Mediterranean, but not analytically for Greece (Lazoglou and Anagnostopoulou, 2019;De Luca et al, 2020;Hochman et al, 2022;Vogel et al, 2021). WCCEs may have a negative short-term socioeconomic impact due to low temperatures and heavy precipitation, causing damages to infrastructures, agriculture, electricity outages and transportation disruptions (Houston et al, 2006;Llasat et al, 2014;Vajda et al, 2014).…”

Investigation of the extreme wet–cold compound events changes between 2025–2049 and 1980–2004 using regional simulations in Greece

“…It has been reported that WCCEs affect the region of the Mediterranean Basin, including Greece (Zhang et al, 2021). Studies us-ing only observational data at some locations (Lazoglou and Anagnostopoulou, 2019), or modeled data mostly over the broader region of the Mediterranean Sea (Vogel et al, 2021;Hochman et al, 2022;de Luca et al, 2020), concerning WCCEs have been conducted in the past, but not depicting analytically WCCEs in Greece, a country that as a part of the Mediterranean Basin is considered a "climate change hotspot" (Ali et al, 2022). This work attempts to fill this void on the effects of climate change on WCCEs in Greece.…”