La Nina rains supreme

AN initial wrap up of the 2022 weather has revealed some major contrasts across Tasmania. The Bureau of Meteoroogy will release its full climate report for 2022 next month but an early look at the data shows Tasmania’s West Coast region and particularly the South-West, received very much below average rainfall last year.

In contrast, the BOM maps show rain on the state’s East Coast was very much above average Overall Tasmania had 1318.75mm of rainfall 2022, as an area average across the state, which is 2.9 per cent below average. Last year was also Tasmania’s equal-10th warmest year on record, equal with 2005. The average temperature was 0.57C warmer than the 1961- 1990 annual average, while also being the warmest year for Tasmania overall since 2018. The BOM says its data shows 2022 was wetter and warmer than average for Australia overall. National mean temperature was 0.5C warmer than the 1961-1990 average, making 2022 the equal 22nd warmest year on record since national temperature records began in 1910. Rainfall, however, was the standout feature of last year’s weather. The BOM says national rainfall was 25 per cent above the 1961-1990 annual average making 2022 the ninth-wettest year on record.

Rainfall was very much above average for the south-eastern quarter of the mainland, where persistent rain saw significant flooding affecting large areas, multiple times during the year. However, rainfall was below average for western Tasmania, much of the north of the Northern Territory, and the far southwest of Western Australia.

Water storage levels have been high across much of Australia during last year, but storages were still low for parts of central coast Queensland, western Tasmania, southeast New South Wales and western Victoria.

Annual maximum temperatures were above average for most of northern Australia, Tasmania and parts of the west coast but below average for New South Wales, southern Queensland and parts of South Australia. Annual minimum temperatures were above or very much above average for most of Australia.

The BOM says the wetter-than-average conditions across much of eastern Australia were consistent with the wet phase of natural climate variability for the region due to La Niña, a negative Indian Ocean Dipole in winter and spring, and a persistently positive phase of the Southern Annular Mode from mid-autumn.

The 2022–2023 La Niña has been the third in a row. It is only the fourth time three successive La Niña events in a row have been observed in the Bureau’s record since 1900.

The BOM will release its full Annual Climate Statement for 2022 in February, which will include a full analysis and report on the year’s rainfall, temperature, water storages, climate influences and more in relation to long-term climate trends.