On New Year’s Day in Esquimalt in 1872, it didn’t rain, but the temperature dipped about five degrees below zero. The city had showers for the following two days.
Typical grey days for the West Coast, these are the oldest recorded weather records in B.C., measured from the province’s first weather station, taken about half a year after B.C. entered Confederation with Canada.
Rolling forward 140 years, and the province is covered in weather stations – almost 6,800 between provincial government ministries, B.C. Hydro, RioTintoAlcan and Environment Canada.
After a four year effort, the Pacific Climate Impacts Consortium (PCIC) has amassed the sum total of B.C.’s recorded weather history into one online database, and which is open to the public.
“The data wasn’t organized in one place or easy to get at,” said Francis Zwiers, director of PCIC, based at the University of Victoria, and which studies the impact of climate change and climate variability in B.C. and the Yukon. “We took on the task of gathering it up and building a tool to access it.”
The database hold about 390 million observations spanning 140 years, from temperature, humidity, rain, wind and in cases snowfall, and adds new data daily. Zwiers said certainly in the early days the record is thin, but weather stations started sprouting up as aviation took off.
“For temperature trends for the province as a whole, then you probably can’t start before 1900. There just isn’t enough stations,” Zwiers said. “The provincial mean temperature is most reliable post-World War II. Lots of stations were put into the system for civil aviation.”
These days weather stations generate highly accurate data that can feed into the Internet in real time. Zwiers, who worked for Environment Canada for part of his career, said even in the old days technicians carefully calibrated weather instruments, which generally produced reliable data. Problems generally crop up if the devices aren’t sited properly, such as too close to a building.
Taken as a whole, B.C.’s weather record shows a net temperature increase of about 1.6 C (plus or minus 0.4 C), but Zwiers cautions the data has a lot of variability. The average temperature declines over a shorter, 110-year window of data, he noted.
The data set will allow PCIC to create high-resolution climatology maps of interest to forestry and environmental assessment companies. Zwiers suspects government agencies such as Ministry of Forests and Ministry of Environment, municipal engineering departments, climate researchers and historians will find uses for the weather data portal.
“There are a lot of weather buffs in the province and people interested in how the climate changes over time,” Zwiers said.
“We expect the information to be invaluable to researchers, engineers, industry and anyone with a keen interest in the climate of the province or its historical weather. These observations will contribute to everyone’s understanding of climate in the province as it continues to evolve.”