Issued 14 December 2022

Introduction

Using data from 1 January to 30 November 2022, we can summarise the year-to-date status of Australia's climate and water resources and provide an indication of the possible end of year values and rankings for Australia's mean annual temperature and area averaged rainfall.

What has the temperature been like?

For Australia as a whole, the mean temperature for January to November was 0.56 °C above the 1961–1990 average. This ranks as the 20th-warmest value for the January–November mean temperature in the 113 years of national records since 1910. Mean temperatures for January to November were very much above average (in the highest 10% of historical observations compared to all years since 1910) across most of the northern tropics and much of Tasmania. They were above average (in the highest 30% of historical observations) for the remainder of the northern tropics, most of Victoria, and parts of Western Australia.

January to November mean temperatures were cooler than average only in small pockets in some inland areas; the largest being in central and northern New South Wales.

Australia's maximum temperature for January to November 0.38 °C above average, the coolest since 2012. Australia's minimum temperature for January to November was 0.73 °C above average, the equal 11th-warmest on record.

Warmth was persistent across the north during autumn, with extreme heatwave conditions affecting the north and west throughout summer and early autumn. For autumn as a whole, the mean temperature was the second-highest on record for northern Australia (north of 26°S).

July was unusually cool for large parts of the tropics due to unusual dry-season rainfall, before September and October again saw much warmer than average temperatures for far northern Australia.

September and October were much cooler than average for much of mainland Australia south of the northern tropics as spring brought increasingly wet conditions. November was particularly cool, rounding out the 6th-coolest mean maximum temperature on record for spring for south-eastern Australia (south of 33°S, east of 135°E).

Where has it rained?

For Australia as a whole, rainfall for January to November was 24% above average, the ninth-highest since national rainfall records begin in 1900, and the highest for January–November since 2011.

Rainfall for January to November was above average for most of Australia, and very much above average (in the highest 10% of historical observations) for the south-eastern quarter of the mainland, but below average for western Tasmania, the eastern half of the Top End of the Northern Territory, and far south-west Western Australia. For south-eastern Australia (south of 33°S, east of 135°E), January–November rainfall was the third-highest on record.

Flooding occurred across the eastern mainland multiple times during 2022, in some cases for extended periods.

Significant flooding affected south-eastern Queensland in January before extreme multi-day rainfall in late February and March produced record-breaking floods in south-eastern Queensland and eastern New South Wales. For details see Special Climate Statement 76.

Heavy rain again brought flooding to some coastal catchments of New South Wales and parts of eastern Victoria in early April.

An East Coast Low in early July caused major flooding around Sydney and along the New South Wales coast, with heavy rain leading to daily rainfall records at many sites.

From August, persistent rain falling onto already wet catchments saw flooding in parts of the eastern states. During September floods affected inland areas of southern Queensland and New South Wales, with minor or moderate flooding also reported in parts of northern Tasmania and north-eastern Victoria. In many parts of the Murray–Darling Basin the flooding occurred over prolonged periods, or on multiple occasions, continuing to affect a number of communities throughout October and into November. A Special Climate Statement summarising rainfall and flooding during this period will be published in due course.

Spring as a whole was the wettest on record for south-eastern Australia, with October the wettest on record and November the third-wettest.

What does this mean for water storages?

With high rainfall, wet soils, and high streamflow conditions, water storage levels have been high across much of Australia during the first 11 months of 2022. The major water storages in the Murray–Darling Basin finished November at 99% full capacity, with many individual storages above 100% of total capacity.

At the end of November, storages for capital cities were above 80%, except for Perth (58%). With the long-term decline of surface water inflows into storages, Perth's water supply is generally more reliant on desalination and groundwater sources than surface water.

While many storages were close to full capacity throughout 2022, some storages started the year well below capacity before experiencing significant filling events.

Storage levels across south-eastern Queensland experienced significant increases across summer 2021–22, with rapid rises particularly in late February following significant rainfall associated with a slow-moving trough. Wivenhoe, the largest storage in south-east Queensland, was below 50% capacity at the start of January but by the end of February had exceeded its full supply capacity for the first time since June 2015. Wivenhoe was at 79% at the end of November.

Late summer rainfall also saw storage levels in northern Australia increase, reaching above 80% capacity at the end of February. Lake Argyle's levels have since steadily decreased, falling to 60% as at the end of November.

Low storage conditions have been experienced across the year for some regions, including parts of central coast Queensland, western Tasmania, south-east New South Wales, and western Victoria. Storage volumes in Tasmania generally tracked lower than for the same time in 2021, remaining around half of full capacity over spring as a result of below average rainfall over the west of the state during most months of 2022.

What is the outlook for the rest of the year?

The long-range forecast issued on 1 December, indicates that December rainfall is likely to be above median for parts of the eastern states and around the coast of the Top End of the Northern Territory. However, below median rainfall is likely for most of north-west Western Australia.

December maximum temperatures are likely to be above median for most of western and central Australia, extending into western Queensland and northern South Australia. Below median maximum temperatures are likely for most of south-eastern Australia, the south coast of Western Australia and north-eastern Australia. December minimum temperatures are very likely to be above median for north-east Australia and likely above median for Tasmania. Below median minimum temperatures are likely over south-west Western Australia, and central and eastern parts of New South Wales.

Taken together with the January–November observations, this means that for the year as a whole, 2022 is likely to be amongst Australia's top 25 warmest years on record (since 1910), but is unlikely to be amongst the top 15 warmest, (i.e. the final rank is anticipated to be between 25th- and 15th-warmest), and similar to 2021.

The area-averaged rainfall for the year to November has already exceeded the 1961–1990 annual average and the 2021 annual rainfall. However, with long-range forecasts suggesting an increased chance of below median rainfall for large parts of Australia during December, 2022 is likely to be in the 20 highest annual totals but not likely to rise into the top 10.

What has been driving weather in 2022?

La Niña and negative Indian Ocean Dipole combine for a very wet year

While back-to-back La Niña events have occurred in approximately half of all past events since 1900, three La Niña events in a row is less common. With a third successive La Niña in 2022, it is only the fourth time this has been observed in the Bureau record since 1900 (with the others being 1954–57, 1973–76, and 1998–2001).

The La Niña of 2021–22 peaked in mid-summer and weakened over autumn 2022. A negative Indian Ocean Dipole (IOD) event emerged in June, before being re-joined by La Niña from the start of September.

La Niña typically increases the chance of above-average rainfall for northern and eastern Australia during spring and summer. When La Niña and negative IOD conditions combine, the likelihood of above average rainfall over Australia is further increased, particularly for the eastern half of the continent. Together they also increase the chances of warmer nights for northern Australia, and cooler days for much of the eastern mainland.

The Southern Annular Mode (SAM) was positive for much of the time from mid-autumn onwards. Positive SAM increases the chance of below average rainfall for parts of south-west and south-east Australia during winter. During spring positive SAM increases the chance of below average rainfall in western Tasmania, but typically leads to above-average rainfall in eastern parts of New South Wales and Victoria, and south-eastern Queensland.

While the negative IOD dissipated at the end of spring, the current La Niña is expected to continue into early 2023.

Climate change also continues to influence Australian and global climate. Australia's climate has warmed by around 1.47 °C over the 1910–2021 period, with an increase in extreme heat events and an increased likelihood of high intensity short duration rainfall events as reported in State of the Climate 2022.

Global temperature

On 6 November 2022 the World Meteorological Organization (WMO) released its provisional report on the State of the Global Climate in 2022, based on data for the first nine months of 2022. The WMO reported that 2022 is likely to between the fifth- and sixth-warmest years on record for the globe, with the past eight years (2015 to 2022) on track to be the eight warmest on record.

On 9 August 2022 the Intergovernmental Panel on Climate Change (IPCC) released its . It found that global surface temperature was 1.09 °C, with an estimated range of 0.95 to 1.20 °C, higher in 2011–2020 than in 1850–1900. The report also states the global surface temperature for the decade 2013–2022 was 1.14 °C higher than during the period 1850–1900, with an estimated range of 1.02 °C to 1.27 °C. This compares with 1.09 °C for 2011–2020, as reported by the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report for Working Group I, released in August 2021.