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Western Australia (commonly abbreviated as WA) is
a state of Australia, occupying the entire western
third of the Australian continent. It is bordered by
the Indian Ocean to the north and west, the Great
Australian Bight and Indian Ocean to the south, the
Northern Territory to the north-east and South
Australia to the south-east. Western Australia is
Australia's largest state and the second largest
subnational entity in the world. It has 2.2 million
inhabitants (10% of the national total), 85% of whom
live in the south-west corner of the state.
The state's capital city is Perth. The people of
Western Australia are sometimes referred to as
sandgropers, the common name of an insect found on
sand dunes around Perth.
The first European to visit Western Australia was
the Dutch explorer Dirk Hartog, who visited the
Western Australian coast in 1616. The British
established a military outpost at King George Sound,
near present-day Albany, in 1826, which was followed
by the establishment of the Swan River Colony in
1829, including the townsite of the present-day
capital, Perth. Western Australia achieved
self-government in 1890, and later federated with
the other British colonies in Australia in 1901.
Today Western Australia's economy mainly relies on
mining, agriculture and tourism. WA supplies 36% of
Australia's overseas exports and is the third
largest iron-ore producer in the world.
Western Australia is bounded by South Australia and
the Northern Territory to the east, and the Indian
Ocean to the west and north. The International
Hydrographic Organization (IHO) designates the body
of water south of the continent as part of the
Indian Ocean, although they are officially gazetted
as the Southern Ocean in Australia.
The total distance of the state's eastern borders is
1,862 km (1,157 mi), and there is 12,889 km (8,009
mi) of coastline. The total land area occupied by
the state is 2.5 million km2.
The southwest coastal area has a Mediterranean
climate and was originally heavily forested,
including large stands of the karri, one of the
tallest trees in the world. This agricultural region
of Western Australia is in the top nine terrestrial
habitats for terrestrial biodiversity, with a higher
proportion of endemic species than most other
equivalent regions. Thanks to the offshore Leeuwin
Current the area numbers in the top six regions for
marine biodiversity, containing the most southerly
coral reefs in the world.
Average annual rainfall varies from 300 millimetres
(12 in) at the edge of the Wheatbelt region to 1,400
millimetres (55 in) in the wettest areas near
Northcliffe, but in the months of November to March
evaporation exceeds rainfall, and it is generally
very dry. Plants must be adapted to this as well as
the extreme poverty of all soils. A major reduction
in winter rainfall has been observed since the
mid-1970s, with a greater number of extreme rainfall
events in the summer months.
The central four-fifths of the state is semiarid or
desert and is lightly inhabited with the only
significant activity being mining. Annual rainfall
averages 200–250 millimetres (8–10 in), most of
which occurs in sporadic torrential falls related to
cyclone events in summer months.
An exception to this is the northern tropical
regions. The Kimberley has an extremely hot
monsoonal climate with average annual rainfall
ranging from 500 to 1,500 millimetres (20–60 in),
but there is a very long almost rainless season from
April to November. Eighty-five percent of the
state's runoff occurs in the Kimberley, but because
it occurs in violent floods and because of the
insurmountable poverty of the generally shallow
soils, the only development has taken place along
the Ord River.
Occurrence of snow in the state is rare, and
typically only in the Stirling Range near Albany, as
it is the only mountain range far enough south and
with sufficient elevation. More rarely, snow can
fall on the nearby Porongurup Range. Snow outside
these areas is a major event; it usually occurs in
hilly areas of southwestern Australia. The most
widespread low-level snow occurred on 26 June 1956
when snow was reported in the Perth Hills, as far
north as Wongan Hills and as far east as Salmon
Gums. However, even in the Stirling Range, snowfalls
rarely exceed 5 cm (2 in) and rarely settle for more
than one day.
The highest observed maximum temperature of 50.5 °C
(122.9 °F) was recorded at Mardie, Pilbara, 61.6
kilometres (38.3 mi) from Barrow Island on 19
February 1998. The lowest minimum temperature
recorded was -7.2 °C (19.0 °F) at Eyre Bird
Observatory on 17 August 2008.
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