Dynamical and cloud-radiation feedbacks in El Nino and greenhouse warming

An El Nino-like steady response is found in a greenhouse warming simulation resulting from coupled ocean-atmosphere dynamical feedbacks similar to tho se producing the present-day El Ninos. There is a strong negative cloud-rad iation feedback on the sea surface temperature (SST) anomaly associated wit h this enhanced eastern equatorial Pacific warm pattern. However, this nega tive feedback is overwhelmed by the positive dynamical feedbacks and cannot diminish the sensitivity of the tropical SST to enhanced greenhouse gas co ncentrations. The enhanced eastern-Pacific warming in the coupled ocean-atm osphere system suggests that coupled dynamics can strengthen this sensitivi ty.