A second contingent of New Zealand firefighters is heading to North America to help fight hundreds of wildfires.

And climate change experts say while the wildfires so far haven't afflicted us so badly, we're likely to see more extreme weather events as climate change continues.

Sixty-five firefighters will fly to Canada shortly, and can expect to be using techniques they learn when they get back home as climate change bites.

Firefighter team leader John Sutton says: "It's almost like a boost to morale, someone cares and someone's here to help."

The experience they gain will be invaluable ahead of the fires they say will burn New Zealand this summer.

"They are becoming more intense and complex and it's a way of training our people and developing their skills," Mr Sutton says.

Thirty-eight New Zealand firefighters are already in California, and are among the more than 15,000 people tackling 18 blazes.

"This has been a challenging and deadly fire season just in the month of July," California Department of Forestry and Fire Protection chief Ken Pimlott said.

"Four firefighters perished fighting the fires in california many many members of the public have been put at risk, injured and a number of fatalities."

Europe too is touching record temperatures above the 40degC mark as fires burn out of control in the Iberian Peninsula.

In Australia it's still winter, but fire is licking the Pacific Highway too - and the sun is parching the soil further inland, taking farmers beyond breaking point in the worst drought since 1965.

Charity worker Edwina Robertson broke down as she told Australia's Prime Minister of another rural suicide.

Scientists say extreme heatwaves are now twice as likely, as weather events that used to be exceptional become expected.

Weather experts say because of climate change, New Zealand will be no different from the rest of the world - there will be more extreme weather events, more wildfires, more droughts and more floods.

Victoria University climate scientist James Renwick says climate change has forced the temperature up 1degC - but warns at present rates of carbon dioxide emission, it'll rise by another 1degC in just two decades.

"Pretty much the whole of the eastern part of New Zealand - that's from south of Dunedin right through to East Cape - would be in that very high or extreme danger zone for four or five or six months of the year."

Newshub.