Is climate change causing B.C.'s extreme weather? Expert is unsure.

An extreme weather researcher says it's not yet clear whether this year's floods and heat waves in British Columbia can be attributed to human-caused climate change.

Aseem Sharma with Natural Resources Canada says extreme weather events are expected to be more "common, stronger and broader" in the future and he's calling for more research to determine its cause.

Sharma says more rain along with atmospheric rivers are expected in the fall of La Nina years, like 2021, but current projections also indicate a "significant increase" in extreme weather may be linked to climate change.

He says B.C. usually experiences about 35 atmospheric rivers a year, and while global warming may bring more extreme weather, they are sometimes localized events.

He points to weather stations in Hope and Abbotsford, which set a record for precipitation in November.

Sharma says average daily precipitation extremes have increased in intensity, particularly since 2010, but because local trends often differ from the global average, it is difficult to definitively attribute the cause to a warming climate.

He says more in-depth analysis will help improve seasonal forecasts of events like the heat waves and floods in B.C. this year, and arm communities with the knowledge they need to minimize risks associated with such events.

B.C. recorded Canada's highest-ever temperature during the so-called heat dome in June at 49.6 C.

In mid-November, torrential rains flooded low-lying areas, quickly pushed rivers over their banks and forced the evacuation of thousands of southern B.C. residents.

This report by The Canadian Press was first published Dec. 15, 2021.