Lightning occurrence patterns over Canada and adjacent United States from lightning detection network observations

Abstract

IntroductionContinuous real-time coverage of lightning occurrence across southern Canada has been available since the installation of the Canadian portion of the integrated North American Lightning Detection Network (NALDN) was completed in February 1998. The Canadian Lightning Detection Network (CLDN) consists of 82 sensors that detect lightning over most of Canada to approximately 65°N in the far west, 55°N in the far east, and offshore to about 300 km. Previous information on lightning occurrence was available only in the vicinity of staffed meteorological observing sites or in limited areas covered by provincial agencies (e.g., Clodman and Chisholm, 1996;Kochtubajda et al., 2002). There were vast stretches of the country where knowledge was lacking. The incidence of lightning in Canada has likely been underestimated in traditional climatologies based on observations available before the CLDN was installed. For example, in a study of Atlantic Canada using CLDN data, Lewis (2000) found that during two winters, December to April 1998April -1999April and 1999April -2000 separate thunderstorm days were identified by the ten-station surface weather network but the CLDN network detected 41 separate thunderstorm days over land for the same period. He further noted that since the installation of the CLDN it is apparent that winter lightning occurs far more frequently off the coast of Atlantic Canada than had been previously suspected or forecast. While a true lightning climatology is probably several years away from definition, we believe there are now sufficient data to identify significant features of lightning occurrence patterns over the portion of Canada covered by the CLDN. We show national summary results, and expand in greater detail for three diverse regions. Where possible we suggest physical reasons for significant observed features. Emphasis is on Canadian lightning patterns but we do comment on some interesting features found over the northern United States. In discussions we assume that the reader is familiar with locations, boundaries, and names of political jurisdictions, and major geographical features in both countries.

A case study of aerosol scavenging in a biomass burning plume over eastern Canada during the 2011 BORTAS field experiment

“…Finally, high numbers of lightning strikes associated with this system were detected by the Canadian Lightning Detection Network (Burrows et al, 2002). Thunderstorms were observed at The Pas between 07:00 and 09:00 UTC, and a total rainfall of 11.4 mm was recorded during this event.…”

A performance assessment of the World Wide Lightning Location Network (WWLLN) via comparison with the Canadian Lightning Detection Network (CLDN)

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A radar‐based methodology for preparing a severe thunderstorm climatology in central Alberta

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