Sorry for the delay in getting this out as I just recently received a response.
Good day,
We thank you for your inquiry on December 1st regarding the instruments used at our weather stations to measure temperature and dew point. We apologize for the delay in responding to your request.
In Canada, ECCC's Automatic Weather Stations (AWS) is the primary surface weather observing network. For temperature measurement these stations currently use the YSI 44212EC temperature probe, which has a temperature range of -50°C to +50°C (±0.09°C linearity) with an accuracy of +/- 0.1°C.
For humidity measurements, our stations currently use the Vaisala HMP155 humidity probe. The measurement range of this sensor is 0 to 100% RH with the following accuracy specifications:
±1% RH (at 15° to 25°C, 0 to 90% RH)
±1.7% RH (at 15° to 25°C, 90 to 100% RH)
±(1.4 + 0.032 × reading) % RH (at -60° to -40°C)
±(1.2 + 0.012 × reading) % RH (at -40° to -20°C)
±(1.0 + 0.008 × reading) % RH (at -20° to +40°C) ± (1.2 + 0.012 × reading) % RH (at 40° to 60°C)
At the majority of our sites, the temperature and humidity sensors are kept in a ventilated Stevenson screen and the sensors are installed at approximately 1.5 metres above ground level. In some remote locations where grid power is not available, the temperature and humidity probes are housed in unventilated Stevenson screens or unventilated Gill shields. Approximately 70% of our network of just under 600 stations have ventilated screens.
We hope this answers your inquiry. Do not hesitate to contact us if you have any other questions. The Meteorological Service of Canada (MSC) is a primary supplier of meteorological information in Canada, and is continuously monitoring and maintaining its observation networks to ensure Canadians have access to reliable weather and climate data.
Best regards,
Manita Essurredeen
MSC's National Inquiry Response Team (NIRT)
ISO 9001:2015
Environment and Climate Change Canada
