What does a negative indian ocean dipole indicate
The Indian Ocean Dipole (IOD), also known as the Indian Nino, niño is an irregular oscillation of-sea surface temperatures in which the Western Indian ocean becomes alternately warmer and then colder than the eastern part of the. oceanet evidence from fossil coral reefs demonstrates that the IOD has functioned since at least the middle of the Holocene period, 6500 years ago. An average of four each positive/negative IOD events occur during each 30-year period with each event lasting around six months. 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.ike ENSO, the change in temperature gradients across the Indian Ocean results in changes in the preferred regions of rising and descending moisture and air. In scientific terms, the IOD is a coupled ocean and atmosphere phenomenon, similar to ENSO but in the equatorial Indian Ocean. The Indian Ocean Dipole (IOD) is a coupled ocean-atmosphere phenomenon in the Indian Ocean. It is normally characterized by anomalous cooling of SST in the south eastern equatorial Indian Ocean and anomalous warming of SST in the western equatorial Indian Ocean.he Indian Ocean Dipole (IOD) is a coupled ocean-atmosphere phenomenon in the Indian Ocean. It is normally characterized by anomalous cooling of SST in the south eastern equatorial Indian Ocean and anomalous warming of SST in the western equatorial Indian Ocean. Accordingly, the waters in the eastern Indian Ocean cools down, which tends to cause droughts in adjacent land areas of Indonesia and Australia. Conversely, during a negative IOD period the waters of the tropical eastern Indian Ocean is warmer than water in the tropical western Indian Ocean.he Indian Ocean Dipole (IOD) and the El Nino are independent climatic phenomena but often co-occur. Both IOD and El Nino result in change of global wind patterns. Water temperatures around the Mentawai Islands dropped about 4° Celsius during the height of a positive phase of the Indian Ocean Dipole in November of 1997. During these events unusually strong winds from the east push warm surface water towards Africa, allowing cold water to upwell along the Sumatran coast.et evidence from fossil coral reefs demonstrates that the IOD has functioned since at least the middle of the Holocene period, 6500 years ago. An average of four each positive/negative IOD events occur during each 30-year period with each event lasting around six months. The Indian Ocean Dipole (IOD) and the El Nino are independent climatic phenomena but often co-occur. Both IOD and El Nino result in change of global wind patterns.To know about the change of wind patterns, click here.However the cycle of IOD is shorter, while El Nino condition could last for even two years.he Indian Ocean Dipole (IOD) and the El Nino are independent climatic phenomena but often co-occur. Both IOD and El Nino result in change of global wind patterns. It is thought that the IOD has a link with ENSO events through an extension of the Walker Circulation to the west and associated Indonesian throughflow (the flow of warm tropical ocean water from the Pacific into the Indian Ocean).ike ENSO, the change in temperature gradients across the Indian Ocean results in changes in the preferred regions of rising and descending moisture and air. In scientific terms, the IOD is a coupled ocean and atmosphere phenomenon, similar to ENSO but in the equatorial Indian Ocean. A Theory for the Indian Ocean Dipole Mode Tim Li, Bin Wang, C.-P. Chang*, and Yongsheng Zhang International Pacific Research Center, University of Hawaii, Honolulu, Hawaii *Department of Meteorology, Naval Postgraduate School, Monterey, California (Submitted to J. Atmos.apley, and R.H. Stewart, 1999: Anomalous warming in the Indian Ocean coincident with El Nino. J.Geophys.Res ., 104, 10523-10533. Chang, C.-P., and T. Li, 2000: A theory for the tropical tropospheric biennial oscillation. Hence, positive IOD events are often associated with El Nino niño and negative events With La. Nina niña WHEN the IOD and enso are in phase the Impacts Of el Nino Niño and la nina niña events are Often, most extreme over australia while when they are out of Phase The impacts Of El nino niño and la. nina niña events can be diminishedike ENSO, the change in temperature gradients across the Indian Ocean results in changes in the preferred regions of rising and descending moisture and air. In scientific terms, the IOD is a coupled ocean and atmosphere phenomenon, similar to ENSO but in the equatorial Indian Ocean. A ‘positive IOD’ — or simply ‘IOD’ — is associated with cooler than normal sea-surface temperatures in the eastern equatorial Indian Ocean and warmer than normal sea-surface temperatures in the western tropical Indian Ocean.urrent observations show neutral IOD conditions over the Indian Ocean. But most parts of the tropical Indian Ocean, particularly the southern tropical Indian Ocean, are warmer. Studies have linked conditions like these to below-normal rainfall over India.
The waters of the tropical eastern Indian Ocean is warmer than water in the tropical western Indian Ocean.