By Brian Kahn
The numbers are in, and Australia just finished it’s hottest year since record-keeping began in 1910. Not only was 2013 the hottest year on record, but it featured other notable milestones, from adding a new color to the temperature map to a wild and damaging start to bushfire season. And while the calendar has turned to 2014, the weather appears stuck in 2013.
The Australian Bureau of Meteorology (BOM) released its 2013 numbers on Jan. 3. They show that the average annual temperature in Australia was 73.4 degrees F, which was 2.16 degrees F above average based on average temperatures for 1961-1990. That beats the previous record set in 2005 by 0.31 degree F.
The state of South Australia beat its previous record by an even greater margin. There, the average temperature was 0.74 degree F above the previous record.
What’s perhaps even more notable is that not a single part of the country experienced below average temperatures for the year. No other year can claim that distinction dating back to at least 1990. When the previous record was set in 2005, at least 2.9 percent of the country was below the median temperature, the BOM stated.
The record warmth in 2013 is in line with temperature trends in Australia and around the world, which have been linked in part to rising greenhouse gas concentrations in the atmosphere. The last 10 years tied for Australia’s warmest 10-year period since record-keeping began. Since 1910, temperatures have warmed on the continent by about 1.8 degrees F and have risen particularly sharply since 1990. Since 1960, the number of record hot days recorded across the continent have also doubled.
The annual average temperature only tells part of the story. Much of the country experienced prolonged hot spells throughout the year. A heat wave gripped the country in January and saw temperatures skyrocket to 18 degrees F above average at times, leading to the addition of a new color on the BOM’s temperature map to depict the hottest areas. The widespread heat wave contributed to January 2013 being the hottest January on record, running 3.2 degrees F above average, and the entire summer season was also the hottest since records began in 1910.
A report released in June showed that climate change likely increased the odds of that heat wave. The extreme weather of the past summer could also be the norm by 2040 as the impacts of global warming intensify, the study found.
Winter didn’t quite match the summer anomalies, but overall it was the third warmest winter on record for the country. September, the start of spring, saw temperature shoot back into record territory. This past September’s average temperature was almost 5 degrees F above normal, making it not only the hottest September on record but also the most anomalously warm month ever recorded in Australia.
High spring temperatures coupled with the lingering effects of a dry winter led to an outbreak of bushfires in the state of New South Wales that turned Sydney’s skies orange in September and October. According to the BOM, the fires were the worst to hit the Sydney area since 1968.
Scientists have not yet seen evidence of a direct connection between manmade global warming and the number of bushfires or acres burned in Australia. However, studies show that extreme fire weather days, with high temperatures and dry, windy conditions, have become more common in southeastern Australia over the past 30 years, while the fire season has grown longer. Those trends are likely to continue into the future as well, particularly in areas where Australia’s worst bushfires occur, scientists have said.
Warm temperatures weren’t solely isolated to the land areas of Australia. Ocean temperatures near Australia were 0.92 degree F above average during 2013, sufficient for earning a spot as the third warmest on record. That’s notable since the top two years were 1998 and 2010, both La Niña years. During those years, a pool of warmer than average water stretches across the western Pacific, including along parts of Australia’s northern and eastern coastlines. La Niña conditions were largely absent during 2013.
Overall, the oceans near Australia have warmed 1.2 degrees F since 1910. Temperatures have increased at a faster rate since 1950, and there hasn’t been a cooler than average year since 1994. According to the 2012 Marine Climate Change Report Card, Australia’s coastal waters could warm 3.6 degrees F to 5.4 degrees F by the end of the century if greenhouse gas emissions continue to increase at a rapid rate.
La Niña and its opposite phase El Niño both influence land temperatures as well. Generally El Niño improves the odds of Australia having warmer than normal temperatures in the winter and spring while La Niña can lead to warmer temperatures in the summer. The absence of both La Niña and El Niño is another reason why 2013’s record-breaking heat in Australia was so impressive.
Though the calendar officially reads 2014, Australia’s weather didn’t appear to get the memo. The mercury is likely to top out near 106 degrees F in Brisbane on Saturday and 102 degrees F for northern and western parts of New South Wales. Stradbroke Island, a popular vacation destination near Brisbane, saw 900 campers evacuated on Dec. 29 due to a bushfire. As of Jan. 3, the fire had burned 8,649 acres, but authorities say the forecast for hot weather and shifting winds could mean the worst is yet to come. To the south in New South Wales, severe fire conditions and burn bans are also in place for the northwest part of the state.
Looking further ahead through March, the Bureau of Meteorology continues to forecast above normal temperatures for roughly two-thirds of the country.
Climate Central, based Princeton, N.J., is an independent organization of scientists and journalists researching and reporting on the science and impacts of climate change.
Image credit: Australian Bureau of Meteorology