COMNISPA II: Update of a mid-European isotope climate record, 11 ka to present

We present an update (COMNISPA II) of a precisely dated, high-resolution speleothem δ18O record from the Austrian Alps. COMNISPA II consists of five stalagmites from Spannagel Cave, which have comparable δ18O values within periods of simultaneous growth and show similar δ18O variations on centennial to millennial timescales. This allows combining the five stalagmites to one composite record using a newly developed statistical approach. The COMNISPA II stack differs slightly from the previous version, but is better constrained because of additional stalagmites used for the reconstruction and a more objective method used for constructing the composite record. Furthermore, the record now covers the last 11 ka and shows variations in δ18O values by about 2‰. As previously shown, these variations compare well with other records in central Europe and the North Atlantic, and thus reflect a large-scale climate evolution.