A 560 yr summer temperature reconstruction for the Western Mediterranean basin based on stable carbon isotopes from Pinus nigra ssp. laricio (Corsica/France)

Abstract

The Mediterranean is considered as an area which will be affected strongly by current climate change. However, temperature records for the past centuries which can contribute to a better understanding of future climate changes are still sparse for this region. Carbon isotope chronologies from tree-rings often mirror temperature history but their application as climate proxies is difficult due to the influence of the anthropogenic change in atmospheric CO2 on the carbon isotope fractionation during photosynthetic CO2 uptake. We tested the influence of different correction models accounting for plant response to increased atmospheric CO2 on four annually resolved long-term carbon isotope records (between 400 and 800 yr) derived from Corsican pine trees (Pinus nigra ssp. laricio) growing at ecologically varying mountain sites on the island of Corsica. The different correction factors have only a minor influence on the main climate signals and resulting temperature reconstructions. Carbon isotope series show strong correlations with summer temperature and precipitation. A summer temperature reconstruction (1448-2007 AD) reveals that the Little Ice Age was characterised by low, but not extremely low temperatures on Corsica. Temperatures have been to modern temperatures at around 1500 AD. The reconstruction reveals warm summers during 1480-1520 and 1950-2007 AD and cool summers during 1580-1620 and 1820-1890 AD. © Author(s) 2012.