Climate-induced variations in arthropod habitats of the Circum-Sicilian islands according to convection permitting simulations of the Mediterranean driven by CMIP6 and PMIP4 data

Arthropods play vital roles in the ecosystem (e.g., pollinators, decomposers, biological pest control), and thus can act as indicators of ecosystem integrity. The state of these ecosystems is sensitive to variations in climate conditions, especially on small islands. The Circum-Sicilian islands are a chain of small islands around Sicily in the central Mediterranean. With the use of Convection permitting simulations, many of these islands can finally be adequately resolved. The objective of the project PALEOSIM (PALEOclimate modelling of Small Islands in the Mediterranean and possible impacts on arthropod habitats) is to study climate impacts on the habitats of arthropods (mainly insects) in the Circum-Sicilian islands. To achieve this, RegCM5 is driven by CMIP6 and PMIP4 data for a 3 km region covering the west and central Mediterranean.

Climate indices from the simulations have been used to assess the ecological niche of select arthropod species and hence determine how these conditions have changed across different time scales. The data used to drive RegCM5 allows for the study of time slices across several scenarios, which include: the last glacial maximum, mid-Holocene, ~1000 CE, ~1850 CE, ~1995 CE (a historical baseline), and Global Warming Levels of 1.5, 2, and 3 °C. This analysis reveals how some species are especially sensitive to changes in climate conditions, and the significant threat of the current climate crisis.