Vertical Structure and Diabatic Processes of the MJO: A Global Model Evaluation Project

Given the central role of the diabatic heating for prevailing MJO theories and demands for reducing the model deficiencies in simulating the MJO, it is of great interest and urgent need to explore how the MJO vertical heating structures are represented in current GCMs. Through a collaborative effort between the Year of Tropical Convection (YOTC) / MJO Task Force (www.ucar.edu/yotc/mjo.html) and the GEWEX Atmospheric System Study (GASS) (www.gewex.org/gcss.html), we are coordinating a model and observation intercomparison project on diabatic heating associated with the MJO. Based on this project, the diabatic heating associated with the MJO will be examined in three experimental components, i.e., i) climatological simulation; ii) short-term / detailed-“physics” hindcasts, and iii) less-detailed but longer-lead hindcasts extending from ii); and with the hindcasts focusing on MJO events during the period of YOTC (and DYNAMO experiment). Detailed descriptions of these experiment designs can be found on the project website (www.ucar.edu/yotc/mjodiab.html). This presentation will provide an overview of this activity and any preliminary results that are available by the time of the meeting.