Russell C. Coile
Thunderstorms at High Altitudes in the Tropics
Note on Thunderstorms at High Altitudes in the Tropics
R. C. Coile* and W. Culmsee**
Journal of Geophysical Research (the continuation of Terrestrial
Magnetism And Atmospheric Electricity (1896-1948)), Volume 58, June,
1953, Number 2
Compilation of some of the thunderstorm data of the Huancayo Magnetic
Observatory has revealed some interesting points of comparison with the
data published by C. E. P. Brooks on the distribution of thunderstorms over
Meteorological data for the years 1931 to 1939, inclusive,
were examined to determine the number of thunderstorms recorded during
each month. The data for 1933 were not used in the fi nal analysis, for
the unusually low number of thunderstorms recorded in that year looked
obviously due to poor observational technique.
Table 1 contains the tabulations of the number of days when thunder
was heard in each month for the period 1931 to 1939. The total number of
thunderstorms for each year is also given. The eight years of data, excluding
1933, have an average number of storms per year of 105.2. Dr. Brooks had
computed an average number of 42.6 thunderstorms occurring in a year in
the districtBrazil, Bolivia, and Peru.
Figure 1 presents a curve of the annual variation of frequency of
thunder at Huancayo, Peru (latitude 12° 02.7' south and longitude 75°
20.4' west), as computed from the eight years of data tabulated in Table 1.
For comparison, the curves of annual variation of thunderstorms at Quito,
Ecuador (latitude 0° 14' south and longitude 78° 45' west), and Brooks'
district of Brazil, Bolivia, and Peru have also been plotted. It is interesting
to note how different are the curves for Quito and Huancayo. Quito,
altitude 9,350 feet, with an average of 99.5 storms per year, was the only
meteorological observatory listed for the Andes or for the whole west coast
of South America for that matter. However, the data of Huancayo, altitude
11,000 feet, does not have the characteristics of such sharp peaks as
recorded in April and October at Quito.