The reported increase in numbers of tornadoes in recent years may reflect more reporting by citizens and media involvement rather than an actual increase in tornado occurrence (although some natural increase has not been ruled out), in addition to better detection technology i.e. Doppler weather radar and satellite imagery. The upswing could also be attributed to other factors, such as improved aerial and ground damage assessment after the fact in sparsely populated areas (particularly the case in remote parts of the Canadian Prairies and Northern Ontario, for example), better trained spotter capabilities and increased use of digital recording devices by citizens. Tornadoes in Canada are enough of a threat for a public warning system to be in place, overseen by the national weather agency, Environment Canada (EC).