Climate response to the mitigation scenario RCP 8

Climate response to the mitigation scenario RCP 8. 5 simulated by SP-CCSM 4 and CCSM 4 Objectives: (a) Detect whether the projections of vertical wind shear in the RCP 8. 5 scenario are sensitive to the parameterization of cloud process; (b) Investigate how the ENSO-shear relationship is projected in warmer climate by a different parameterization of cloud processes. Impact: (a) The suppression of convection over the western Africa in SP-CCSM 4 is stronger than in CCSM 4. As a result, SP-CCSM 4 projects increased westerlies at 200 h. Pa that further contributes to an increased vertical wind shear over the equatorial Atlantic. (b) in the RCP 8. 5 scenario, projection of the ENSO-shear relationship by the SP-CCSM 4, with and without long-term linear trend, retains similar features as in observation. Conversely, the ENSO-shear relationship, with long-term trend, over the equatorial Atlantic projected by the CCSM 4 is opposite to that in SP-CCSM 4 and observation. The regression coefficients of vertical wind shear with Niño 3. 4 index for (a) SP-CCSM 4 and (b) CCSM 4. Shading represents 95% significance level. X. Zhu, L. Xu, and X. Zhu, 2014: Projected changes of the tropical Atlantic vertical wind shear and its relationship with ENSO in the SP-CCSM 4. Journal of Climate, doi: http: //dx. doi. org/10. 1175/JCLI-D-14 -00002. 1