Query: The answer lies in the summer’s record-breaking heat, say wildfire experts.

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2019–20 Australian bushfire season <=SEP=> The 2019–20 Australian bushfire season, colloquially known as Black Summer, was a period of unusually intense bushfires in many parts of Australia. In June 2019, the Queensland Fire and Emergency Service acting director warned of the potential for an early start to the bushfire season which normally starts in August. The warning was based on the Northern Australia bushfire seasonal outlook noting exceptional dry conditions and a lack of soil moisture, combined with early fires in central Queensland. Throughout the summer, hundreds of fires burnt, mainly in the southeast of the country. The major fires peaked during December–January. As of 9 March 2020, the fires burnt an estimated 18.6 million hectares (46 million acres; 186,000 square kilometres; 72,000 square miles), destroyed over 5,900 buildings (including 2,779 homes) and killed at least 34 people. Nearly three billion terrestrial vertebrates alone – the vast majority being reptiles – were affected and some endangered species were believed to be driven to extinction. At its peak, air quality dropped to hazardous levels in all southern and eastern states. The cost of dealing with the bushfires is expected to exceed the A$4.4 billion of the 2009 Black Saturday fires, and tourism sector revenues fell by more than A$1 billion. However, economists estimated that the Australian bushfires may cost over A$103 billion in property damage and economic losses, making the bushfires Australia's costliest natural disaster to date. Nearly 80 percent of Australians were affected either directly or indirectly by the bushfires.  By 7 January 2020, the smoke had moved approximately 11,000 kilometres (6,800 mi) across the South Pacific Ocean to Chile and Argentina. As of 2 January 2020, NASA estimated that 306 million tonnes (337 million short tons) of CO2 had been emitted.From September 2019 to March 2020, fires heavily impacted various regions of the state of New South Wales. In eastern and north-eastern Victoria large areas of forest burnt out of control for four weeks before the fires emerged from the forests in late December. Multiple states of emergency were declared across New South Wales, Victoria, and the Australian Capital Territory. Reinforcements from all over Australia were called in to assist fighting the fires and relieve exhausted local crews in New South Wales. The Australian Defence Force was mobilised to provide air support to the firefighting effort and to provide manpower and logistical support. Firefighters, supplies and equipment from Canada, New Zealand, Singapore and the United States, among others, helped fight the fires, especially in New South Wales.During the ensuing crisis, an air tanker and two helicopters crashed during firefighting operations, the air tanker crash resulting in the deaths of the three crew. Two fire trucks were caught in fatal incidents caused directly by fire conditions, killing three fire fighters.By 4 March 2020, all fires in New South Wales had been extinguished completely (to the point where there were no fires in the state for the first time since July 2019), and the Victoria fires had all been contained. The last fire of the season occurred in Lake Clifton, Western Australia, in early May.There has been considerable debate regarding the underlying cause of the intensity and scale of the fires, including the role of fire management practices and climate change, which during the peak of the crisis attracted significant international attention. Politicians visiting fire impacted areas received mixed responses, in particular Prime Minister Scott Morrison. An estimated A$500 million was donated by the public at large, international organisations, public figures and celebrities for victim relief and wildlife recovery. Convoys of donated food, clothing and livestock feed were sent to affected areas.

Bushfires in Australia <=SEP=> Bushfires in Australia are frequent events during the warmer months of the year , due to Australia 's mostly hot , dry climate . Each year , such fires impact extensive areas . On one hand , they can cause property damage and loss of human life . On the other hand , certain native flora in Australia have evolved to rely on bushfires as a means of reproduction , and fire events are an interwoven and an essential part of the ecology of the continent . For thousands of years , Indigenous Australians have used fire to foster grasslands for hunting and to clear tracks through dense vegetation .   Major firestorms that result in severe loss of life are often named based on the day on which they occur , such as Ash Wednesday and Black Saturday . Some of the most intense , extensive and deadly bushfires commonly occur during droughts and heat waves , such as the 2009 Southern Australia heat wave , which precipitated the conditions during the 2009 Black Saturday bushfires in which 173 people lost their lives . Other major conflagrations include the 1983 Ash Wednesday bushfires , the 2003 Eastern Victorian alpine bushfires and the 2006 December Bushfires .   Global warming is increasing the frequency and severity of bushfires .

2010 Russian wildfires <=SEP=> The 2010 Russian wildfires were several hundred wildfires that broke out across Russia , primarily in the west in summer 2010 . They started burning in late July and lasted until early September 2010 . The fires were associated with record-high temperatures , which were attributed to climate change -- the summer had been the hottest recorded in Russian history -- and drought .   Russian President Dmitry Medvedev declared a state of emergency in seven regions , and 28 other regions were under a state of emergency due to crop failures caused by the drought . The fires cost roughly $ 15 billion in damages .   A combination of the smoke from the fires , producing heavy smog blanketing large urban regions and the record-breaking heat wave put stress on the Russian healthcare system . Munich Re estimated that in all , 56,000 people died from the effects of the smog and the heat wave . The 2010 wildfires were the worst on record to that time ; in 2012 , however , new wildfires broke out , and they proved even more extensive and damaging .