Climate variability on multiple time scales: Monsoon bursts and El Nino clash over SE Asia Dr. Matthew Wheeler Bureau of Meteorology Research Centre, Melbourne, Australia

Outline n El Nino and SE Asian drought n Madden Julian Oscillation and monsoon bursts u Jakartas February floods n Climate Change n Sustainable Development

Smoke from fires in Indonesia affecting Manila in September 1997 The impacts of El Nino drought-induced fires in Indonesia

El Nino as seen in Pacific Ocean Temperatures West Pacific East Pacific

Madden-Julian Oscillation (MJO) Jakartas floods of Jan/Feb 2002 n 30 to 60-day period n Generates active and break periods/bursts of the monsoon n Involved in monsoon onset and tropical cyclone development. Monsoon break Monsoon westerlies TC formation Westerly Wind Burst ACTIVE BURST OF INDONESIAN-AUSTRALIAN MONSOON Trade Wind surge Approximate 1 month sequence

Satellite-observed clouds/rainfall AREA AVERAGE Outgoing Longwave Radiation (OLR) Low values = clouds and rain High values = clear skies

Satellite-observed clouds/rainfall AREA AVERAGE Outgoing Longwave Radiation (OLR) Low values = clouds and rain High values = clear skies MJO Jakarta floods

The MJO as a wave in the weather 2.5 o N o S The signal of the MJO in the clouds as it moves eastward.

The MJO as a wave in the weather 2.5 o N o S The signal of the MJO in the clouds as it moves eastward. Jakarta floods { MJO

n New technique, using digital signal processing of satellite data n Used to predict the active versus break periods n Calculated daily 2.5 o N o S - An Example forecast from the 13th of January Prediction of the MJO Jakarta floods { OBSERVATIONS FORECAST 13th JANUARY

MJO Prediction: Example maps from 13th Jan Initial Condition Week 1 forecast Week 2 forecast Week 3 forecast JAN JAN JAN 28 JAN - 3 FEB { Floods

The Multiple Time Scales of Climate Weather MJO/monsoon bursts Annual cycle El Nino/La Nina Decadal Variability Climate Change Time scale increasing

MJO interaction with El Nino Monsoon break Monsoon westerlies TC formation Westerly Wind Burst ACTIVE BURST OF INDONESIAN-AUSTRALIAN MONSOON Trade Wind surge Ocean wave MJO sequence (~ 1 month) Possible El Nino 6-12 months later

Climate Variability and Sustainable Development n Prediction is useful, but gains can also be made just by acknowledging that such variability exists. n Our vulnerability is often increasing. n The climate science is important, but so is the partnership with the human dimensions.