文摘
Relationships between the lightning detection network data and human-reported thunderstorms were studied in Estonia during the period of 2006-011. Estonia is located in northeastern Europe between 57.5° to 59.5° N and 21° to 28.5° E. Numbers of thunderstorm days (TD) and thunderstorm hours (TH) reported by 61 volunteer observers and six meteorological stations were compared to the data of the lightning detection network. Results indicated that the flash data within 9.0?km from the sites of volunteer observers should be used in order to derive TD numbers equal to human observations. Larger radius of 14.7?km was found on the basis of six meteorological stations with probably better quality of thunderstorm observations. Due to data quality issues, the daily and monthly numbers of THs reported by individual observers explained only 12-9?% of variations in the flash counts within 40?km of their observing sites. In contrast, the average TH data of all observers successfully explained 75-6?% of variations in daily and monthly flash counts within 40?km of the observation sites. The main advantage of using the average data of many human observers seems to be that in case of a dense network, the neighboring observers tend to compensate for each other’s errors. In general, intense storms close to observing sites were found to be most successfully reported by human observers. The most important conclusion of the study is that although human observations of thunderstorms and automatic lightning observations are very different methods, they generally give similar results.