NINO3.4 Index

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  • NINO3.4
NINO3.4 Index

The NINO3.4 index is one of several El Niņo/Southern Oscillation (ENSO) indicators based on sea surface temperatures.

NINO3.4 is the average sea surface temperature anomaly in the region bounded by 5°N to 5°S, from 170°W to 120°W. This region has large variability on El Niņo time scales, and is close to the region where changes in local sea-surface temperature are important for shifting the large region of rainfall typically located in the far western Pacific.

An El Niņo or La Niņa event is identified if the 5-month running-average of the NINO3.4 index exceeds +0.4°C for El Niņo or -0.4°C for La Niņa for at least 6 consecutive months.

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Heat building in WA

15:03 AEDT After escaping the worst of the heatwave that has scorched eastern Australia this month, the mercury is on the rise in southwestern parts of Western Australia.

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