I was re-reading Tony Hillerman’s mystery novel, Skinwalkers, a couple of weeks ago. The book was written in the
mid-1980s and published by Harper-Row in 1986. On page 172 I found the
following:
“Howard Morgan,
the weatherman on Channel 7, had said there was a 30 percent
chance of rain in
the Four Corners today. That was the best odds
of the summer so far.
Morgan said the summer monsoon might finally
be coming.”
This made me wonder who first used the term “monsoon” to describe the summer thunderstorm season and attendant rainfall in Arizona and New
Mexico. After considerable digging, it appears that
“monsoon” was first used by Ronald L. Ives (1949) in his article: Climate of the
Sonoran Desert Region (Annals of the
Association. of American Geographers, 39:3,
143-187). I could be mistaken in this, but Ives’ Section: “The Sonoran Monsoon”
does not refer to any previous papers. He primarily uses the character of the
annual rainfall at different locations to invoke the use of monsoon terminology
and mentions the winds only peripherally, referring to the seasonal reversal of
pressure gradients driven by spring heating over the Great
Basin.
Ives also may be the originator of the “But it’s a dry heat…” He states the
following about the Sonoran
Desert: "Because of
low relative humidities, sensible temperatures are tolerable, and complaints of summer season discomfort are heard largely from
the obese, alcoholic, and neurotic components of the population."
Reid A. Bryson and William P. Lowry (Synoptic Climatology of
the Arizona
Summer Precipitation Singularity, 1957: Bull.
Amer. Meteor. Soc., 36, 329-339)
are often referred to in papers about the monsoon; however, they did not use
the term in that paper. But, in their 1955 report on research funded by the
USAF (Scientific Report No. 1:
Synoptic Climatology of the Arizona Summer Monsoon, Dept. of Meteorology, The
Univ. of Wisconsin) they stated:
“To the extent
that there has been a rather sharp change of dominant air mass and
seasonal wind
direction in Arizona
with general rains following the change, one might
say that the area had come under the influence
of a ‘monsoon’.”
The seasonal wind change they refer is the monthly change in
average wind direction at 500 mb from June to July. They then discuss the
difficulties in determining whether or not a monsoon had occurred in any given
year. They conclude that, from 1930 through 1954, 8 years occurred clearly with a monsoon and 12 years were clearly without a monsoon, while 5 years were
indeterminate.
Bryson (photo below from 1981) was a very well-known climatologist at the University of Wisconsin. He spent a year visiting at the University of Arizona in the middle 1950s, which led to his research on the summer rains here.
Obviously, there has been some degree of confusion
regarding the “monsoon” continuing through the decades. If anyone is aware of an earlier work that uses "monsoon" for this part of the world, please let me know.
