Abstract

Tree-ring series from ENSO rainfall impact regions reconstruct the tropical Pacific SST field with a high degree of skill back to 1100 CE. 2. Two very different reconstruction methods produce similar results and each can only reconstruct the leading EOF mode of SST variability. 3. Reconstructions extending back 1100 CE do not reveal any clear increase in El Niño variability, but do show a recent overall SST warming.