News / Science & Technology
Medieval Warm Period in Central Europe
Was there really a global Medieval Warm Period? The IPCC used to acknowledge there was; but they have long since changed their view on the subject. Mounting evidence, however, suggests they were wrong to do so; and in this summary, new and important data from Central Europe that support their original belief are described and discussed.
Filippi et al. (1999) 1 obtained stable isotope data (delta 18O and delta 13C) from bulk carbonate and ostracode calcite in a radiocarbon-dated sediment core removed from Lake Neuchatel in the western Swiss Lowlands at the foot of the Jura Mountains, which they used to reconstruct the climatic history of that region over the past 1500 years. And in doing so, they determined that mean annual air temperature dropped by about 1.5°C during the transition from the Medieval Warm Period (MWP) to the Little IceAge (LIA). In addition, they state that "the warming during the 20th century does not seem to have fully compensated the cooling at the MWP-LIA transition" and that during the Medieval Warm Period, mean annual air temperatures were "on average higher than at present."
