Australia, parts of Africa and South America report record-high readings
By Summit Voice
FRISCO — At the start of meteorological autumn for the southern hemisphere, The Australian Bureau of Meteorology reports that the country recorded its hottest-ever summer season, breaking the 1997-1998 mark by 0.1 degrees Celsius.
The most extreme heat was in the beginning of January, when a heat wave settled across much of Australia, including Tasmania, leading to wildfires and record-high readings in parts of the country, with temperatures soaring as high as 49.6 degrees Celsius (121 degrees fahrenheit).
More than 10 pecent of the sites used for long-term climate monitoring reported all-time daily high temperature readings, more than in any previous summer. Both Sydney (45.8 degrees Celcius) and Hobart (41.8 degrees Celsius) reported all-time record highs.
Australian climate trackers also said a stretch of seven days Jan. 2-8) with the average maximum daily temperature for Australia exceeding 39 degrees celsius also set a new record for an extended heat wave, more than twice as long as the previous record set in 1973.
The bureau’s climate experts are clear about linking Australia’s exceptionally hot summer with global warming, explaining that the country has warmed by about 1 degree Celsius since 191o, “consistent with warming observed in the global atmosphere and oceans.”
Most previous record-hot summers in Australia have been associated with El Niño conditions, when warmer-than-average sea surface temperatures prevail across the equatorial Pacific Ocean.
“This essentially means that the record was consistent with warming trends, and achieved without an extra push from natural variability associated with El Niño,” experts wrote in The Conversation, an educational website that reports on science issues.
Higher average temperatures tilt the odds toward more extreme episodes of heat. Similar to the U.S., record highs have been outnumbering record low readings by a ratio of about three to one. About a third of the all-time record high temperatures at the Bureau’s long-term stations have occurred since 2000.
The latest global analyses have found that extreme high temperatures are increasing in frequency almost throughout the world, and the Australian results are consistent with that picture.
Australia wasn’t alone in reporting record high temperatures during the Austral summer. Land surface temperatures across the southern hemisphere were record warm in both December and January.
Those numbers won’t be confirmed until mid-March, but preliminary records indicate it will be a record-warm summer for most of those land areas. Large parts of southern Africa recorded the hottest January on record.
Hotter temperatures were also recorded in large parts of Argentina, Chile and Brazil, while temperatures in parts of Patagonia were more than 4 degrees Celsius above normal in January.
The bureau also reported that it was the driest summer in Australia since 2004-2005, and that the record warmth follows a pattern of extremely hot summers in various parts of the world over the past few years.
For further information go to www.bom.gov.au/climate/change/