A、Both global warming and below-average rainfall. B、Both below-average rainfall and natural climate variability. C、Global warmin

(22) Australia has experienced its warmest August on record, as winter temperatures soared. Australia’s Bureau of Meteorology says that August was a "most extraordinary month" with mean temperatures almost 2. 5 degrees above the long-term average. August in Australia culminated in a record-breaking heatwave across much of the continent. Blair Trewin from the National Climate Center says the past month brought unprecedented weather. "Early last week we saw a number of locations in northern New South Wales and southern Queensland break their August record-high temperatures by four or five degrees," Trewin said. "And to break records by that sort of margin is something which is extremely rare." (23)Scientists think that such unseasonal temperatures are the result of both global warming and natural climate variability. There are warnings that spring in this part of the southern hemisphere is likely to bring more hot weather, causing a long drought. Parts of Australia have seen below-average rainfall for several years and the outlook for many parched communities is not good. (24) Australia is a major food exporter, and if the drought dramatically cuts yields, that could cause global prices for grain, meat and other foods to rise. (25)The warm, dry conditions have prompted the authorities to warn that Australia’s annual bushfire season is again likely to be severe. Already serious fires have flared near Sydney, the country’s most populous city.
22. Why is August said to be a "most extraordinary month"?
23. What do the unseasonal temperatures result from according to the scientists?
24. What will the long drought lead to?
25. What is another concern for Australia?