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 El Nino and SE Asian drought

Madden Julian Oscillation and monsoon “bursts” Jakarta’s February floods

Climate Change

Sustainable Development

Smoke from fires in Indonesia affecting Manila in September 1997

The impacts of El Nino

1997-98 drought-induced fires in Indonesia

El Nino as seen in Pacific Ocean Temperatures

West Pacific

East Pacific

Madden-Julian Oscillation (MJO)

Jakarta’s floods of Jan/Feb 2002

30 to 60-day period

Generates “active” and “break” periods/bursts of the monsoon

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 wavein the weather

2.5oN -12.5oS -

2001

2002

The signal of the MJOin the clouds as itmoves eastward.

The MJO as a wavein the weather

2.5oN -12.5oS -

2001

2002

The signal of the MJOin the clouds as itmoves eastward.

Jakarta floods {

MJO

New technique, using digital signal processing of satellite data Used to predict the active versus break periods Calculated daily

2.5oN -12.5oS -

An Example forecast from the 13th of January

Prediction of the MJO

Jakarta floods{

OB

SE

RV

ATIO

NS

FOR

EC

AST

13th JANUARY

MJO Prediction: Example maps from 13th Jan

Initial Condition

Week 1 forecast

Week 2 forecast

Week 3 forecast

7 - 13 JAN

14 - 20 JAN

21 - 27 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 scaleincreasing

MJOinteractionwith 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

Prediction is useful, but gains can also be made just by acknowledging that such variability exists.

Our vulnerability is often increasing.

The climate science is important, but so is the partnership with the human dimensions.