Auxiliary Material for Paper 2012GL053322 
   
Evaluation of monsoon seasonality and the tropospheric biennial oscillation 
transitions in the CMIP models

Yue Li, Nicolas C. Jourdain, and Andrea S. Taschetto 
Climate Change Research Centre, University of New South Wales, 
Sydney, New South Wales, Australia

Caroline C. Ummenhofer 
Department of Physical Oceanography, Woods Hole Oceanographic Institution, 
Woods Hole, Massachusetts, USA

Karumuri Ashok 
Centre for Climate Change Research, Indian Institute of Tropical Meteorology, 
Pune, India

Alexander Sen Gupta
Climate Change Research Centre, University of New South Wales, 
Sydney, New South Wales, Australia


Li, Y., N. C. Jourdain, A. S. Taschetto, C. C. Ummenhofer, K. Ashok, and A. Sen 
Gupta (2012), Evaluation of monsoon seasonality and the tropospheric biennial 
oscillation transitions in the CMIP models, Geophys. Res. Lett., 39, L20713, 
doi:10.1029/2012GL053322.

Introduction

This auxiliary material contains two figures. Figure S1 illustrates the 
results of Monte Carlo technique applied to observations based on land-
only regions. Figure S2 shows the enhanced predictability results for 
CMIP3 and CMIP5 models, similar to Figure 3, but based on extended 
regions.

1. 2012gl053322-fs01.eps 
Figure S1. Percentage of successful (a) Indian-Indian out-of-phase 
transitions and (b) Indian-Australian in-phase transitions based on 
observational datasets (AIR/AWAP). Purple vertical lines indicate the 
observed percentage of successful transition events relative to the total 
number of possible transition events. The curves represent the associated 
cumulative distribution of successful transition percentages based on 
Monte Carlo random resampling (see text). The median of the distribution 
is shown in the red horizontal line and the red dash indicates the 
enhanced predictability of the observed metric relative to the random 
distribution.

2. 2012gl053322-fs02.eps 
Figure S2. Percentage enhanced predictability for the (a) Indian-
Australian, (b) Indian-Indian, (c) Australian-Indian and (d) Australian-
Australian transitions for observations and CMIP3 and CMIP5 models based 
on the extended regions for which at least one ensemble member for that 
model and for at least one of the transitions shows a significant 
increase in predictability. Circles represent individual ensemble members 
(marked in red are significant, p<0.1). Bars represent the multi-ensemble 
mean percentage enhanced predictability for each model with yellow 
indicating significant changes. The multi-ensemble mean predictability 
was calculated by concatenating time series for all ensemble members 
prior to Monte Carlo resampling.