• DOI:10.5194/CPD-7-2355-2011
• Corpus ID: 55950382

Revisiting the humid Roman hypothesis: novel analyses depict oscillating patterns

@article{Dermody2011RevisitingTH,
  title={Revisiting the humid Roman hypothesis: novel analyses depict oscillating patterns},
  author={Brian J. Dermody and Hugo J. Boer and Marc F. P. Bierkens and Susanne L. Weber and M.J.infoeu-repo Wassen and Stefan C. Dekker},
  journal={Climate of The Past Discussions},
  year={2011},
  volume={7},
  pages={2355-2389}
}

• B. J. Dermody, H. Boer, +3 authors S. Dekker
• Published 14 July 2011
• Environmental Science, Geography
• Climate of The Past Discussions

Previous studies have proposed that potential vegetation in the Mediterranean maintained a wetter climate during the Roman Period until the initiation of large scale deforestation. The reduction in evapotranspirative fluxes associated with deforestation is suggested to have caused climatic aridification leading to the establishment of the present-day Mediterranean climate. There is also evidence to indicate that during the Roman Period Mediterranean climate was influenced by low frequency fluctuations in sea level pressure over the North Atlantic, termed here: the Centennial North Atlantic Oscillation (CNAO). In order to understand the importance of each of these mechanisms and disentangle their respective signals in the proxy record, we have employed an interdisciplinary approach that exploits a range of tools and data sources. An analysis of archaeological site distribution and historical texts demonstrate that climate did not increase in aridity since the Roman Period. Using an Earth system model of intermediate complexity prescribed with a reconstruction of ancient deforestation, we find that Mediterranean climate was insensitive to deforestation in the Late Holocene. A novel analysis of a composite of proxy indicators of climatic humidity depicts spatial and temporal patterns consistent with the CNAO. The link between the CNAO during the Roman Period and climatic humidity signals manifest in our composite analysis are demonstrated using a modelling approach. Finally, we present evidence indicating that fluctuations in the CNAO contributed to triggering a societal tipping point in the Eastern Mediterranean at the end of the Roman Period.