Benito, G., Rico, M., Sanchez-Moya, Y., Sopena, A., Thorndycraft, V.R. and Barriendos, M. 2010. The impact of late Holocene climatic variability and land use change on the flood hydrology of the Guadalentin River, southeast Spain. Global and Planetary Change 70: 53-63.
What was done
Working in southeast Spain, the authors state that they reconstructed flood frequencies of the Upper Guadalentin River using "geomorphological evidence, combined with one-dimensional hydraulic modeling and supported by records from documentary sources at Lorca in the lower Guadalentin catchment."
What was learned
Benito et al. report that the combined palaeoflood and documentary records indicate that past floods were clustered during particular time periods: AD 950-1200 (10), AD 1648-1672 (10), AD 1769-1802 (9), AD 1830-1840 (6), and AD 1877-1900 (10), where the first time interval coincides with the Medieval Warm Period and the latter four time intervals all fall within the confines of the Little Ice Age; and calculating mean rates of flood occurrence over each of the five intervals, we obtain a value of 0.40 floods per decade during the Medieval Warm Period, and an average value of 4.31 floods per decade over the four parts of the Little Ice Age, which latter value is more than ten times greater than the mean flood frequency experienced during the Medieval Warm Period.
What it means
If the difference in flood frequency between the Medieval Warm Period and Little Ice Age is as tightly coupled to global temperature conditions as is suggested by Benito et al.'s study, it would appear that southeast Spain has little to fear in the way of increased flooding in a potentially warmer world of the future.