Page:Popular Science Monthly Volume 1.djvu/681

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HAS OUR CLIMATE CHANGED?
HAS OUR CLIMATE CHANGED?[1]
By DANIEL DRAPER, Esq.,
DIRECTOR OF METEOROLOGICAL OBSERVATORY, CENTRAL PARK.

Does the Clearing of Land affect the Fall of Rain?

MUCH solicitude is publicly felt as regards the supposed diminished quantity of water which fell last year—a point of the highest concern. There is a general impression that this alleged deficiency was to such an amount as to endanger a due supply to New York for the current year. And not only this, it has also been asserted that for several years past there has been a steadily occurring diminution in the rainfall. While the quantity of water has thus been becoming less and less, the demand has been becoming greater. Not only has the population of the city increased, but also that of the suburban districts, which derive their supplies from the same water gathering grounds that we do.

I therefore, supposed, since the registering rain gauge furnishes very reliable measures, that it would be useful to examine this subject critically. But, since we have had these gauges in operation only about three years, and as the investigation proved to be full of interest, I was led to draw upon other additional sources of information, selecting such as seemed to be of the most trustworthy kind. By the aid of these the examination has been extended as far back as 1836, and with the following results:

1. As respects the indications given by our own instruments, which may be thoroughly relied on, for the years 1869, 1870, 1871.

For the first of these years, 1869, the total rainfall was 46.82 inches, distributed as follows:

During the first quarter 15.06 inches.
" " second  " 10.24 "
" " third  " 7.72 "
" " fourth  " 13.80 "
———
Total 46.82 inches.

For 1870 the total rainfall was 42.32 inches, distributed as follows:

During the first quarter 12.86 inches.
" " second  " 10.29 "
" " third  " 9.39 "
" " fourth  " 9.78 "
———
Total 42.32 inches.
  1. Abstract from the Meteorological Report of Daniel Draper, Director of Meteorological Observatory, Central Park, to the Commissioners of Public Parks (1871).