Monday, July 03, 2023


1 comment:

NilaY Wankawala said...

Credit Australian government Bureau of metereology

Issued Tuesday 7 July 2023

The latest Climate Driver Update and Climate Model Summary are now available on our website.

El Niño Alert; positive Indian Ocean Dipole possible

The ENSO Outlook remains at El Niño Alert. When El Niño Alert criteria have been met in the past, an El Niño event has developed around 70% of the time.

Central and eastern Pacific sea surface temperatures (SSTs) are exceeding El Niño thresholds. Models indicate a high likelihood of further warming, with SSTs exceeding El Niño thresholds until at least the beginning of the southern hemisphere summer. In terms of atmospheric indicators, recent values of the Southern Oscillation Index (SOI) have risen back to neutral levels, with the 30-day SOI at +1.1 for the 30 days ending 2 July. The 90-day SOI remains close to, but just shy of, El Niño levels. Sustained changes in wind, cloud and broad-scale pressure patterns towards El Niño-like patterns have not yet been observed. This means the Pacific Ocean and atmosphere have yet to become fully coupled, as occurs during El Niño events. El Niño typically suppresses winter–spring rainfall in eastern Australia.

The current status of the ENSO Outlook does not change the long-range forecast of warmer and drier conditions across much of Australia for August to October. The Bureau's climate model takes into account all influences from the oceans and atmosphere when generating its long-range forecasts.

The Indian Ocean Dipole (IOD) is currently neutral. All models suggest a positive IOD is likely to develop in the coming months. A positive IOD typically supresses winter and spring rainfall over much of Australia, and if it coincides with El Niño, it can exacerbate El Niño's drying effect.

The Madden–Julian Oscillation (MJO) is currently weak or indiscernible, and is expected to remain weak in the coming fortnight. The MJO has little influence on Australian rainfall at this time of year.

The Southern Annular Mode (SAM) index is currently negative and is expected to remain negative for a week before returning to neutral values for at least the next two weeks. A negative SAM typically increases rainfall across parts of south-west and south-east Australia, while a neutral SAM has little influence on Australian climate.

Climate change continues to influence Australian and global climates. Global SSTs were the warmest on record for the months of April and May, and the warmest on record for the Australian region during June. The Australian continent has warmed by around 1.47 °C over the period 1910 to 2021. There has also been a trend towards a greater proportion of rainfall from high intensity, short duration rainfall events, especially across northern Australia. Southern Australia has seen a reduction, by 10 to 20%, in cool season (April to October) rainfall in recent decades.
More information

Media liaison (03) 9669 4057
Technical enquiries
Next update expected by 18 July 2023

  21st  July afternoon post Comparative rain till 21st morning: Panji 2525 mms ( 100 ") and Ratnagiri 2572 mms ( 102") cross 100&q...