Recent climate

2016

The period since 2010–11 provided the first cooler than average year since 2001 (i.e. 2011), along with the warmest (2013), third warmest (2014) and fifth-warmest (2015) years on record for Australia (BoM 2012, 2014a, 2015a). (See the Atmosphere report for more details.)

This period included 2011 as the second-highest rainfall year on record. If 2010 is considered, then 2010 and 2011 form the wettest 2-year period on record. Surprisingly, the years 2012–15 were near median at a national scale, although significant local and regional variations occurred. January 2011 was the wettest January on record for Victoria, whereas February 2011 was the wettest on record for South Australia (BoM 2012). January–March 2011 rainfall contributed to some of the most significant flooding seen in Australia, with notable flooding events in the Kimberley, the Northern Territory, Queensland, Tasmania and Victoria.

Conversely, recent years have produced continuing rainfall deficiencies in parts of Australia. Following the end of the most recent La Niña period in autumn 2012, rainfall has been very much below average for large areas of eastern Australia. These areas started 2015 with long-term rainfall deficiencies in place; these deficiencies persisted across Queensland and worsened in south-eastern Australia during the year. Figure WAT3 shows rainfall deficiencies for the 36 months to December 2015, with the lowest decile values in much of Queensland, western Victoria, south-west Western Australia and parts of Tasmania, including areas with the lowest 36-month rainfall on record.

Although Australia has seen near-median total annual rainfalls in recent years, the distribution of higher than average rainfall has been largely in drainage divisions with little or no major water storage infrastructure (Figure WAT4). Consequently, the amount of water held in storage across Australia decreased, year on year, from 2012 to 2015 (Figure WAT5).

During 2015, a decreasing trend in water storage was apparent across all but one drainage division (Table WAT1), increasing the pressure for all water users, including environmental water delivery from managed water distribution systems.

 

Table WAT1 Water held in major public storages across Australia’s drainage divisions

Drainage division

Jan 2015

(% full)

Jan 2016

(% full)

Carpentaria Coasta

100.0

100.0

Lake Eyre Basinb

N/A

N/A

Murray–Darling Basin

52.6

40.4

North East Coast

73.5

65.8

North Western Plateaub

N/A

N/A

Pilbara–Gascoyne

62.3

34.7

South Australian Gulf

68.0

49.4

South East Coastc

68.0

66.2

South West Coast

45.1

30.3

South Western Plateaub

N/A

N/A

Tanami–Timor Sea Coast

98.5

77.7

Tasmania

48.0

38.0

N/A = not applicable

a Only one major public water storage in this division.

b No major public water storages in this division.

c Combined South East Coast (NSW) and South East Coast (Victoria) storages

Source: Bureau of Meteorology, January 2016,

Argent RM (2016). Inland water: Recent climate. In: Australia state of the environment 2016, Australian Government Department of the Environment and Energy, Canberra, https://soe.environment.gov.au/theme/inland-water/topic/2016/recent-climate, DOI 10.4226/94/58b656cfc28d1