Feedbacks of ENSO and Annular Modes

Radiative and Dynamical Feedbacks Driving Temperature Response to ENSO and Annular Mode Variability

This DOE-funded project aims to uncover radiative and dynamical forcing/feedback processes critical for establishing the observed surface and atmospheric temperature response to low-frequency modes of variability in the Earth's climate system, and to investigate how the relative roles of different forcing/feedback processes might evolve with increasing greenhouse gas (GHG) concentration in the atmosphere. We have completed process-based temperature decompositions for ENSO- and NAM (Northern Annular Mode)-related temperature anomalies utilizing the coupled atmosphere-surface climate feedback-response analysis method (CFRAM), whose foundation is the total energy balance within an atmosphere-surface column at any horizontal location.

   

                                                   

Partial temperature anomalies in an El Nino winter due to oceanic dynamics and heat storage anomalies (a), water vapor feedback (b), cloud feedback (c), atmospheric dynamical feedback (d), ozone feedback (e) and surface albedo feedback (f). Unit is K. (Deng et al. 2012a)

 

                                             

 

Vertical profile of the pattern-amplitude projection (PAP) coefficients (color bars) associated with various radiative and dynamical forcing of the NAM+ temperature anomalies in 0°–10°N (a), 30°N–60°N (b), and 75°N–90°N (c). The solid black curves in (a)-(c) indicate the vertical profiles of the observed temperature anomalies averaged over the respective zonal belts. Unit is K. (Deng et al. 2012b)