Declining number of stations was noted in the ECO's report 2018 GREENHOUSE GAS PROGRESS REPORT CLIMATE ACTION IN ONTARIO: WHAT'S NEXT? - (see Appendix D)
CBC New has also referred to this concept in responding to a complaint to the CBC Ombudsman regarding accuracy in reporting on extreme weather trends. What has been cited as evidence of that decline is the chart in Appendix D in the ECO report above. CBC's Director of Journalistic Standards Paul Hambleton wrote:
"The report suggests several possible reasons for this inconsistency, including issues with data collection: There simply are not enough rain gauges. Rainfall data is collected using rain gauge buckets that can record both amount and intensity of rainfall. After a series of federal budget cuts in the 1990s, there are fewer rain gauge stations across the country than there were 60 years ago."
Fewer rain gauge stations? Or fewer "manual" rain gauge stations? Yes there is a difference.
What does that chart show? It summarizes declining manual stations in Canada and is a excerpt from the paper in Atmosphere-ocean An Overview of Surface-Based Precipitation Observations at Environment and Climate Change Canada (Mekis et al., 2018) - https://www.researchgate.net/publication/324041502_An_Overview_of_Surface-Based_Precipitation_Observations_at_Environment_and_Climate_Change_Canada
The chart of manual station count in Canada is Figure 2a in the paper on the left below.
|Number of Manual Climate Stations in Canada|
This chart has been referred to in discussions on extreme rainfall trends. For example, in the ECO report this chart has been related to intensity-duration-frequency of isolated localized storms as in the excerpt at right:
Readers of this blog will have seen extensive analysis of the trends in extreme rainfall across Canada, including annual maximum series and intensity-duration-frequency (IDF) trends. The data used is that of Environment and Climate Change Canada, distributed in the Engineering Climate Datasets.
|Number of Climate Stations in Canada With Rainfall Intensity Analysis|