The National Climate Assessment (NCA) has said that the impacts of climate change on the world are already occurring and that warming could cause up to three quarters of all of Australia’s cities to be affected by extreme heat.

The NCA’s fifth report, released on Monday, is the most detailed and comprehensive assessment of the human impact of climate and weather since the release of the 2007 Climate Change and Health Report by the Australian National University.

The report estimates that temperatures could increase by an average of 3.1C by 2100, with the average temperature rise of 1.7C.

“The impacts of extreme weather events will be especially likely in the south-east, with more than 40 per cent of the states and territories likely to be hit by extreme events in that region by the end of the century,” the report said.

The impacts are expected to be more severe in the east and in the Northern Territory, and will be more intense in the states of South Australia, Queensland, Western Australia and New South Wales.

“In many parts of Australia, temperatures could reach double-digit or triple-digit increases,” it said.

“Most of the increases in the extremes are expected in the west and the Northern Territories, with some regions in the north of the country expected to experience double-digits of the impacts.”

“It’s been quite a while since the last time we saw these extremes in Australia,” the study said.

“This is a really important report for all of us, but especially for those of us living in the southern part of the nation.”

This is about the impact of the changing climate on our communities, on our businesses, and on our ability to survive.

“It said the impacts could occur on the northern states of New South Wramble, Queensland and the Territory.”

Extreme weather events such as heavy rainfall, flooding and bushfires will likely increase in frequency and intensity, particularly in areas where water temperatures are higher,” the NCA said.

It said that while the impacts on individual locations were not yet known, the “tremendous” risks would extend to the north.”

We do expect that the most affected regions will see increased risks to life, health and property due to increased heat, drought and/or other weather extremes,” the statement said.

A heatwave in Sydney in May was the hottest day in Australia since February 2018, with an average temperature of 24.2C.

It comes after a record-breaking heatwave hit the north coast of the Northern Australia region of New England last month, killing at least 14 people.

The heatwave prompted the National Weather Service to warn that the risk of heatwaves in the region was “extremely high”.”

We expect this extreme weather event to become a significant contributor to heatwave risk,” the agency said.

Australia’s largest city, Sydney, has seen its temperature rise by nearly 10C since August.

The state of Victoria has also seen its average temperature increase, with temperatures soaring by 6C over the past two months.

The Northern Territory is also seeing its temperatures increase.

The average temperature in Western Australia was 25.6C on August 24, up from 24.5C on July 24.

In the Territory, the average was 23.7 on August 23, up 1.8C on June 25.

The weather has been especially intense in parts of the NT, with parts of Brisbane, the Gold Coast and the north-eastern coast of New Guinea experiencing record heat.

More than 70 per cent have been hit by bushfires since April, which are expected, and there are more than 200 fires burning across the country.

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