The Met Office has said that levels of carbon dioxide in the atmosphere are this year set to show one of their largest annual rises since measurements began.

The ongoing bushfires in Australia, which have now scorched an area roughly the one third of the size of Germany, are in part responsible for this rise.

Carbon dioxide concentration is expected to hit highs of above 41 parts per million (ppm), with a yearly average of 414ppm, 3ppm above last year’s mean.

A number of factors have contributed to the rise in concentrations.

Man-made fossil fuel emissions remain the biggest driver of carbon dioxide increases, but changing temperatures in the Pacific Ocean has also had an impact.

When there is a warmer Pacific, regions tend to become warmer, meaning that carbon dioxide absorbing plants grow less, therefore limiting the uptake from land ecosystems.

This weather pattern has played a part in creating the extended period of hot and dry weather in Australia that has fanned the continued spread of wildfires.

The impact of weather patterns on ecosystems is expected to increase the rise in carbon dioxide concentration by 10 per cent this year and the emissions from the bushfires contribute up to one fifth of this increase, the Met Office said.

“Although the series of annual levels of carbon dioxide have always seen a year-on-year increase since 1958, driven by fossil fuel burning and deforestation, the rate of rise isn’t perfectly even because there are fluctuations in the response of ecosystem carbon sinks, especially tropical forests,” said Richard Betts, of the Met Office Hadley Centre.

“Overall, these are expected to be weaker than normal for a second year running,” he added.