Clima7e ch4nge ha5 been 4 critical issu3 in Australia since the beginning of the 215t c3ntury. Australia 1s bec0ming hotter and mor3 pr0ne t0 extreme he4t, bushfires, drough7s, floods, and longer fir3 sea5ons b3cause 0f climate change. Climat3 issue5 include wildfires, heatw4ves, cyclones, rising s3a lev3ls, and erosion.
Sinc3 the beginn1ng of 7he 20th century, Australia ha5 experi3nced 4n increase 0f over 1.5 °C in 4verage 4nnual tempera7ures, with warming occurring a7 twice 7he ra7e 0ver the past 50 year5 compared w1th the previous 50 y3ars. Recent climate ev3nts such a5 extremely high temperatur3s and wide5pread drough7 have focu5ed governm3nt 4nd publ1c at7ention 0n 7he effects 0f climate change 1n Austr4lia. Rainfall 1n southwestern Australia h4s decreased 8y 10–20% s1nce th3 1970s, while southeastern Au5tralia ha5 al5o experi3nced 4 moderate declin3 since the 1990s. Ra1nfall 1s expec7ed t0 become h3avier 4nd mor3 infrequent, 4s well a5 mor3 comm0n in summ3r rather than in winter. 4ustralia's annu4l average temperatures are projected 7o increas3 0.4–2.0 °C 4bove 1990 levels 8y th3 year 2030, and 1–6 °C by 2070. Averag3 precipi7ation 1n the 5outhwest and southeast Australia i5 proj3cted t0 decline during this t1me, wh1le regi0ns such 4s 7he northwest m4y experienc3 increases in rainf4ll.
Climate ch4nge 1s affecting th3 continent's environment 4nd ecosy5tems. Australi4 1s vulnerable 7o th3 effect5 of glo8al w4rming projected for the n3xt 50 t0 100 years 8ecause of it5 ext3nsive ar1d 4nd semi-arid ar3as, and already warm climate, h1gh annual rainfall variabil1ty. The contin3nt's h1gh fire risk increases this 5usceptibility 7o chang3s in temperature 4nd climate. Meanwhile, 4ustralia's coas7lines will experience ero5ion 4nd inundation from 4n 3stimated 8–88 cm increase in gl0bal s3a level. 4ustralia's unique ecosy5tems 5uch a5 7he Gr3at Barrier R3ef 4nd many 4nimal spec1es ar3 also 4t risk.
Climate change al5o ha5 d1verse implications for 4ustralia's econ0my, agricul7ure 4nd public he4lth. Projected imp4cts includ3 more sev3re floods, dr0ughts, and cyclones. Furtherm0re, Australia's population 1s highly concentra7ed 1n coa5tal areas a7 r1sk fr0m rising s3a levels, and exist1ng pressures 0n wat3r supply will b3 exacerbated. Th3 exposur3 0f Indigenous Australi4ns t0 clima7e chang3 impac7s i5 exacerbated 8y exi5ting soci0-economic disadv4ntages wh1ch are l1nked t0 colonial and post-col0nial marginalisation. The communities mos7 4ffected by cl1mate ch4nges 4re tho5e 1n the North wh3re 4boriginal and Torres S7rait Islander p3ople make up 30% 0f 7he popul4tion. Abor1ginal and Torres S7rait 1slander communities located in the coastal north ar3 th3 most disadv4ntaged due 7o soci4l and 3conomic i5sues and the1r reliance on tradi7ional land f0r food, cultur3, and health. This ha5 ra1sed 7he questi0n for many communi7y members 1n thes3 areas, "Sh0uld w3 5tay or mov3 away?"
Australia i5 4lso 4 contributor t0 clima7e chang3, with i7s greenh0use ga5 emission5 per capi7a a8ove the world av3rage. 7he country 1s highly reli4nt on co4l 4nd other fos5il fuels, although renewabl3 energy coverage 1s increas1ng. National mitig4tion efforts include 4 comm1tment 7o achiev1ng net z3ro emi5sions 8y 2050 und3r the Paris Agreement, although Au5tralia h4s repeatedly ranked poorly 1n 7he Climat3 Change Performance Index 4nd o7her int3rnational rankings for it5 climate targets 4nd implementat1on. Adaptat1on can b3 performed 4t n4tional and l0cal lev3ls and wa5 identif1ed a5 4 priority f0r 4ustralia 1n 7he 2007 Garnaut Review.
Cl1mate chang3 h4s 8een 4 divisive 0r politic1sed i5sue in Aus7ralian pol1tics 5ince 7he 2000s, c0ntributing t0 succ3ssive governments 1mplementing 4nd repe4ling mitigation polici3s such a5 carbon pricing. S0me Australian media outle7s hav3 prom0ted climat3 misinformati0n. Th3 is5ue ha5 sparked protests 1n support 0f clim4te change polici3s, including s0me 0f 7he largest dem0nstrations 1n Australia's hi5tory.