Australia's Bureau of Meteorology says last year was the second warmest on record and this year could be the planet's hottest.
The bureau says uncharacteristically warm conditions are being felt across the northern hemisphere, with record temperatures.
China has issued a fresh heatwave alert after a week of soaring temperatures.
Parts of Northern Africa, the United States and the Middle East are also experiencing scorching heat, with some regions recording above 50 degrees Celsius.
