Explanation:

Indian ocean Dipole is a recently discovered phenomena that has a significant influence onIndian monsoons.

Indian ocean Dipole is a SST anomaly (Sea Surface Temperature Anomaly – different fromnormal) that occurs occasionally in Northern or Equatorial Indian Ocean Region (IOR). The Indian Ocean Dipole (IOD) is defined by the difference in sea surface temperature between two areas (or poles, hence a dipole) – a western pole in the Arabian Sea (western Indian Ocean) and an eastern pole in the eastern Indian Ocean south of Indonesia. IOD develops in the equatorial region of Indian Ocean from April to May peaking in October. With a positive IOD winds over the Indian Ocean blow from east to west (from Bay of Bengal ntowards Arabian Sea). This results in the Arabian Sea (western Indian Ocean near African Coast) being much warmer and eastern Indian Ocean around Indonesia becoming colder and dry.

In the negative dipole year, reverse happens making Indonesia much warmer and rainier. Positive IOD is good for Indian Monsoons as more evaporation occurs in warm water. Similar to ENSO, the atmospheric component of the IOD is named as Equatorial Indian Ocean mOscillation (EQUINOO)(Oscillation of pressure cells between Bay of Bengal and Arabian Sea).