Dr. Craig Smith
Environment and Climate Change Canada
Research areas
Synthesis of WMO-SPICE Activities and Contributions to CCRN (In collaboration with Dr. Daqing Yang)
In parallel to CCRN activities, Environment and Climate Change Canada Climate Research Division and the Watershed Hydrology and Ecology Research Division participated in the World Meteorological Organization (WMO) Solid Precipitation InterComparison Experiment (SPICE) with contributions that included the operation of two precipitation intercomparison facilities in Saskatchewan. The two facilities, Caribou Creek (53.945°N, 104.649°W) in the southern Boreal forest (near the BERMS Old Jack Pine research site) and Bratt’s Lake (50.200°N, 104.710°W) on the prairies, contributed precipitation intercomparison and ancillary meteorological data to the SPICE project, focusing on the winters of 2013/2014 and 2014/2015 but continuing to collect data through the 2017/2018 winter. With each site measuring precipitation with at least one official WMO Double Fence Automated Reference (DFAR) for solid precipitation, the sites will contribute a high quality legacy precipitation data set which will be made available for multiple research applications.
The core precipitation variables measured at both the Caribou Creek and Bratt’s Lake site include the DFAR, an Alter shielded and an unshielded Geonor precipitation gauge, and snow depth. The Caribou Creek site has additional precipitation measurements by an auto gauge inside a well sheltered bush shielded area (bush gauge) and bi-weekly snow surveys (measuring snow depth and density). Bratt’s Lake hosts two DFAR measurements, with one Geonor and one Pluvio2 gauge, for intercomparison. Data collected specifically for SPICE will be released to the public following the completion of the SPICE final report (fall of 2018) while much of the data collected by ECCC up to March 2018 will be published on the Government of Canada Open Data Portal.
At Caribou Creek during the 2013/2014 and 2014/2015 winters (Nov through March), the DFAR, bush gauge, Alter shielded gauge, and unshielded gauge measured 154 mm and 85 mm, 145 mm and 79 mm, 121 mm and 72 mm, and 98 mm and 59 mm, respectively. For the respective gauge configurations compared to the DFAR, this represents an average undercatch of 7%, 24%, and 52%. Maximum snow depth and snow water equivalent at Caribou Creek were approximately 67 cm and 112 mm for 2013/2014 and 44 cm and 74 mm for 2014/2015. At Bratt’s Lake during the 2013/2014 and 2014/2015 winters (Nov through March), the DFAR, Alter shielded gauge and unshielded gauge measured 101 mm and 110 mm, 40 mm and 49 mm, and 23 mm and 33 mm, respectively. For the respective gauge configurations relative to the DFAR, this represents an average undercatch of 58% and 74%. The relative difference in the gauge bias between the two sites reflects the difference in the wind speeds during winter precipitation, Bratt’s Lake being the much windier site due to exposure. It is also indicative of the impact of shielding on the catch efficiency of the gauges.
Data collected at these two sites during the WMO SPICE project contributed to the development and publication of high frequency (i.e. 30 minute) transfer functions for the single Alter and unshielded Geonor gauge, as well as transfer functions for several other gauge configurations supplied by instrument manufacturers. Snow water equivalent data collected at Caribou Creek were used in the publication of an assessment of automated SWE sensors. These publications can be found in the SPICE special issue of Hydrology and Earth System Sciences (https://www.hydrol-earth-syst-sci.net/special_issue400_78.html).