British Columbia Geography, Climate & Nature

British Columbia is Canada's westernmost province and its third-largest by area, almost four times the size of the United Kingdom and larger than every U.S. state except Alaska. It borders Alberta to the east, Yukon and the Northwest Territories to the north, the U.S. states of Washington, Idaho and Montana to the south, and Alaska to the northwest, with its southern border fixed by the 1846 Oregon Treaty. It is Canada's most mountainous province, dominated by the Coast Mountains along the Pacific coast and the Canadian Rockies further inland, with most of the population concentrated in the Lower Mainland around Vancouver.

The Coast Mountains hold some of the largest temperate-latitude ice fields in the world, their western slopes covered in dense temperate rainforest before tapering to a dry interior plateau. Vancouver Island, home to Victoria, sits off the southwest coast, while Haida Gwaii -- an archipelago of two main islands and roughly 400 smaller ones -- lies further north across Hecate Strait. The Inside Passage, a sheltered coastal shipping route running from Washington state through British Columbia to Alaska, threads through this island-and-fjord coastline and is heavily used by cruise ships and ferries alike.

British Columbia's climate varies sharply with its dramatic terrain. The coast, including Vancouver and Victoria, has a mild, wet oceanic climate with rain concentrated in the winter months and comparatively dry summers. Inland, the Okanagan Valley has a notably sunny, dry climate that supports its fruit-orchard and wine industries, a sharp contrast to the coast just a few hours' drive away.

In the mountains, including around Whistler, a snowy alpine climate supports a major ski industry, with the region regularly recording some of the heaviest snowfall totals in North America. Wildfire risk is real across the grasslands and forests of the BC Interior in summer, and avalanche risk is a genuine hazard in backcountry mountain areas in winter; check current conditions before travelling to either in the relevant season.

British Columbia's Coast Mountains hold some of the largest temperate-latitude ice fields in the world, feeding rivers that run through dense temperate rainforest on the range's western slopes before the terrain tapers to a dry interior plateau. This range of elevation and moisture across a single province, from rainforest coast to near-desert interior valleys to alpine tundra, supports an unusually wide range of ecosystems for one political jurisdiction.

The province's rivers are essential to one of the Pacific Northwest's defining ecological phenomena: the salmon run, in which salmon born in BC's rivers migrate to the ocean and return, with uncanny precision, to their natal streams to spawn. Salmon function as a keystone species across the region, meaning their ecological impact on other wildlife significantly exceeds what their biomass alone would suggest.

Salmon runs are the ecological signature of British Columbia's rivers: Pacific salmon species return from the ocean each year, usually in autumn, to spawn in the exact streams where they were born, navigating first by magnetoreception and then by smell as they near their natal waters. As a keystone species, salmon support a wide web of other wildlife, from bears to eagles, that depend on the annual run.

The province's mountain, forest and coastal habitats support black and grizzly bears, orcas and other marine mammals along the coast and Inside Passage, and a wide range of bird life, though specific wildlife-viewing logistics vary significantly by region and season and are best arranged with a local guide or operator.