Seung H. Baek, Lamont-Doherty Earth Observatory, New York, United States, Jason E Smerdon, Lamont-Doherty Earth Observatory, Palisades, NY, United States, Mingfang Ting, Lamont Doherty Earth Observ, Palisades, NY, United States, Yochanan Kushnir, Columbia Univ, Palisades, NY, United States and Richard Seager, Lamont Doherty Earth Obs, Palisades, NY, United States