|
The graphics and statistical information on this page fill gradually as they become available, with some not available until the next day.
The page is updated every 30 minutes at about 20 and 50 minutes past the hour.
For weather news as it breaks that is tagged and organised, use the links on the Weather and Climate Media Reports page.
 The Centre and Kimberley drown while the south sizzles
After new rainfall records were set yesterday in southern NT, yet more were written today in southwestern NT and northwestern SA as a deep low pressure system carried a stream of tropical moisture into the area. Yesterday, 83.8mm in 24 hours at Yulara Airport, its heaviest for December in nearly 30 years of weather observations, caused sensational waterfalls off Uluru, closed the national park and flooded the Yulara town square.
Record-breaking rainfall in the 24 hours to 9am this morning fell in SW NT and NW SA. Curtin Springs, 80km E of Uluru, had its heaviest 24 hours of rain for any month with 128mm in the gauge. In a weather history of over 60 years, the previous heaviest all-time fall had been 104.6mm on 26 March 1982.
In the Kimberley region in northern WA, floodwaters from torrential rain that fell as the low passed through late last week are working their way down many river systems, the Fitzroy and its tributaries in particular. As detailed in this Guardian article, roads, including the Great Northern Highway, are cut, and evacuations were expected. The strong monsoon flow in the wake of Ex-Tropical Cyclone Yvette is weakening, however, and only showers and thunderstorms are expected for the remainder of the week, mostly in the eastern Kimberley.
Adelaide, Melbourne and a large slice of VIC had a hot Christmas Day and a hot Christmas Night. The official maximum temperature at Adelaide's Kent Town site was 41.3, comprehensively breaking the previous Christmas Day record of 40.1 set in 1945 according to duty forecaster Kenneth Cheung at the BoM. The temperature of 40.7 given in this Guardian article was the highest to 3pm, but the official maximum temperature is for the 24 hours to 9am next day, and the temperature continued to rise after 3pm. Overnight into Boxing Day it was hot and sticky across VIC and northern TAS, with record high minimum temperatures set at several locations. Stations with long periods of record to equal or set new records were Mildura, Ouyen, Essendon and the summit of Mt Wellington behind Hobart.
 Arctic temperatures this winter are up to 30°C above average. What happens now?
Air temperatures near the North Pole are normally around -30°C at this time of year, but in recent days have been closer to -4. A floating meteorological buoy north of the polar island Spitzbergen, around the same latitude as far northern Greenland, last Thursday reported a temperature of zero degrees. Justyna Wodziczko, a Norwegian Meteorological Institute forecaster, told Thomson Reuters that a low pressure system between Greenland and Spitzbergen was driving a very powerful current of air north, bringing much warmer air into the region.
Jesper Eriksen, a forecaster at the Danish Meteorological Institute, added that spikes in Arctic temperatures like these "are becoming more frequent because we have a declining sea ice cover - the water below is warmer." Sea ice is at a record low for this time of year according to the US National Ice and Snow Data Center while the Arctic region is warming at twice the global average. The loss of Arctic sea ice produces a positive feedback loop - solar radiation on a dark sea produces more heat than it would on a white snow cover which in turn increases heat. The additional heat in polar areas also melts the permafrost that underlies tundra on all the polar continents, releasing the powerful greenhouse gas methane as well as vast stores of CO2. This is another positive feedback loop - melting of permafrost leads to more heating which leads to more melting.
Some see the melting of Arctic ice as an advantage; it will open up shipping lanes across the Arctic for transport and tourism, and make extraction of oil and gas feasible as Vladimir Putin and Donald Trump have already suggested. Greenland hopes that mining, fishing and tourism will come with global warming. Others, who see it as a disaster for wildlife in the region and traditional ways of human life there, will think otherwise.
The great unknown, strongly speculated about in scientific circles, is the impact that a hotter Arctic will have on weather patterns across the whole Northern Hemisphere. This short video from The Guardian shows that the speed at which the northern ice cap is melting risks triggering 19 climate tipping points, with disastrous consequences. It could also affect ecosystems elsewhere on Earth, perhaps irreversibly.
| 
