an introduction to the indian ocean dipole zhuomin chen [email protected]
TRANSCRIPT
What is IOD? First described by Dr. Saji et al. in 1999 Second mode of EOF, explains about 12% of the total
variation of anomalous Indian Ocean sea-surface temperatures
Dipole Mode Index (DMI)
Evolution of a Dipole Mode EventAn IOD event usually starts around May or Jun, intensifies in the following months and peaks between Aug and Oct and then rapidly decays.
Positive & Negative Phases of IOD
Positive: cooler in the tropical eastern Indian Ocean and warmer in the tropical western Indian OceanNegative: warmer in the tropical eastern Indian Ocean and cooler in the tropical western Indian Ocean
Positive IOD Phase Negative IOD Phase
IOD Influence on Surrounding Climate
A positive phase of the IOD tends to cause droughts in East Asia and Australia, and flooding in parts of the Indian subcontinent and East Africa.
Australian droughts A 2009 study by Ummenhofer et al. at the University of New
South Wales Climate Change Research Centre, has demonstrated a significant correlation between the IOD and drought in the southern half of Australia, in particular the south-east.
Floods in Kenya, Eastern Africa
Preconditioned major wildfires in southeast Australia Caused coral reef death across western Sumatra Exacerbated malaria outbreaks in East Africa …… A better understanding of the relationship between the
Indian Ocean Dipole and extreme weather events……
However many problems still remain unsolved. have not reached an agreement on how IOD formed; have questions about the relationship between ENSO and
IOD; and how they affect the climate together …… More Effort Counts!
Summary
Thank you!