Victoria Is Already Getting Warmer. Here's the Proof

As covered previously by The Capital, a warming climate is expected to transform Victoria into a city with more heat waves, more violent storms and higher seawalls. Less well known is how much of the local climate has already shifted. According to archival data

The weather data below, provided to The Capital by Canadian weather historian Rolf Campbell , was all gathered at what is now Victoria International Airport, with the first recording made on August 1st, 1940. As Campbell’s graphs illustrate, even 80 years ago Victoria was a much colder and snowier place.

Campbell is also the creator of Victoria Weather Records, an incredibly informative Twitter account compiling daily updates on how Victoria is stacking up against its weather history. Follow it at this link .

When the first soldiers from Victoria embarked east for battlefields in the Second World War, they were leaving a city that, on average, was 0.9 degrees colder than it is now. By global standards, this is a massive shift. According to the NASA Earth Observatory, earth temperatures as a whole have warmed by only 0.8 degrees since 1880. Victoria has thus warmed faster in a much shorter span of time. Compared to the rest of Canada, however, Victoria’s warming is comparatively manageable. Natural Resources Canada estimates that the country as a whole has warmed an average of 1.3 degrees since 1948, and that Canada continues to warm at twice the global rate. With warming being felt most dramatically in colder areas, this means that regions adjoining coastal B.C. have seen temperatures rise more than three times as fast as Victoria. In parts of Banff National Park, it is now up to 3.6 degrees hotter than it was in 1950.

Warmer temperatures naturally mean fewer snow days, to the point where the city sees 14 fewer centimetres of snow than it did 80 years ago. The region-wide decrease in snowfall has been felt most acutely on Mount Washington, where ski seasons can now be as short as two weeks. According to an analysis by UBC, by the end of the century Mount Washington will be too warm to support any skiing at all. Victoria will still be walloped by the occasional city-seizing snowstorm (note the recent spikes in 1996 and 2008), but the trend is towards a city where an annual dusting of snow is the exception, rather than the norm. There are only two completely snow-free years in this graph, and they’ve both occurred in the last 25 years.

Even though Victoria has less snow, it doesn’t mean there’s less water falling from the sky. Since 1940, average rain hitting the city has gone up by 53mm per year; about as much as the length of a pinky finger. It’s not a huge surge (only about 6%), but this too is a preview of coming attractions. While climate change is usually associated with hot, dry conditions (such as those that helped precipitate the devastating fires now sweeping Australia), all that extra hot air is going to be evaporating a lot of water that will have to fall somewhere. This is why B.C. is projecting that by 2050, the province will experience up to 12% more rain. Unfortunately, most of this extra rain is going to arrive as violent winter storms, with longer and more frequent droughts forecast for summers.

As this story is posted, Victoria is certainly not lacking for any high winds. However, on average each year is yielding less and less fuel for Victoria’s various sailing clubs. Since the wind records above began being compiled, the city’s overall windspeed has dropped by 2 km/h. In this, Victoria may be fitting into a wider trend known as “global terrestrial stilling.” The wind blows because of uneven global temperatures; if Arctic temperatures are low and equatorial temperatures are high, the resulting atmospheric mix of hot and cold air is going to give you wind. But as the Arctic warms, these differentials are evening out, slowing global wind speeds by 8 km/h from 1980 to 2010.  However, a recent study in Nature found that wind speeds have started to kick up again over the last decade, which would certainly seem to be reflected in Victoria’s data.

Victoria’s humidity has gone down by 4% since 1940. On this measure, Victoria may appear to be bucking a global trend. As indicated by your winter-cracked hands, the atmosphere’s ability to hold moisture is directly correlated to how warm it is: If the earth gets hotter, it stands to reason that it would also get more humid. In hotter areas of the planet such as India, spikes in humidity may even end up rendering some regions uninhabitable. However, the numbers above are all reflecting relative humidity. Since humidity reading are based on how much water the air is able to hold, the same amount of water in warm air will register as being a lower humidity than if it was in cold air. Thus, if you raise air temperatures while keeping moisture constant, you will see falling humidity readings.

There is one indicator in which absolutely nothing has changed since the 1940s. Snow pack has seen an average change of 0%. To the uninitiated, snow pack would seem to be the same measurement as snow fall (which has trended downwards, as shown in one of the graphs above). However, while snow fall catalogues the total amount of snow that has fallen from the sky, snow pack is merely a measurement of how much sticks to the ground. So, while there is less snow than 80 years ago, the amount that Victorians end up having to shovel from their walks has remained remarkably consistent.