Against the backdrop of extreme weather worldwide, a United Nations body that vets climate change science began meeting in Montreal on Wednesday to shape its next set of reports to help guide policy-makers.

The 46th session of the Intergovernmental Panel on Climate Change runs until Sunday and on the agenda are various reports in the works, including the outline for a sixth assessment report due out in 2022.

Those assessments of research by climate scientists, guided by government decision-makers, help to develop climate policy and to make clean energy choices and economic development plans.

Notably, the input in the voluminous fifth assessment report helped bring about global acceptance for a more ambitious climate approach -- the 2015 Paris Accord.

The deal commits countries to keeping the rise in global temperatures by the year 2100, compared with pre-industrial times, "well below" two degrees Celsius and says they will "endeavour to limit" them even more, to 1.5 C.

Dr. Martine Dubuc, associate Canadian deputy minister of the environment and climate change, told the delegates in Montreal on Wednesday that mapping out the sixth report -- summarizing the work of thousands of scientists around the world -- will help Canada with its own plan.

"The transfer of international scientific knowledge is cutting-edge and played a major role in the implementation of the Paris climate change agreement and the pan-Canadian framework on clean growth and climate change," Dubuc said.

Panel vice-chair Thelma Krug said scientists are guided by policy-makers in 195 member states.

In addition to the larger report produced by the panel, she said three other shorter-term special reports are also coming, including one that looks at the impact of global temperatures of 1.5 C above pre-industrial levels.

Canadian researcher David Grimes, president of the World Meteorological Organization, told delegates that recent disasters underscore the need for groups like his and the panel to work together to adapt to climate extremes.

"International co-operation has never been as important as it has been today, where extreme weather and climate events now account for more than four out of every five disasters worldwide," Grimes said.

"The warning which is occurring in our atmosphere, oceans and climate -- in particular in the polar regions -- is having significant impacts leading to increased severe weather and extreme events like droughts, floods and forest fires, like those having devastated Canada's westernmost province this summer," he added, referring to wildfires in British Columbia.

Environment Minister Catherine McKenna and Science Minister Kirsty Duncan addressed the opening session in separate pre-recorded videos.

"The world is shifting to cleaner forms of energy," McKenna said. "The environmental challenges we face require global collaboration, action and solutions."

The panel will return to Canada in March 2018, when Edmonton will host a meeting to look at the impact of climate change on cities.