The Montgomery advertiser., 1901-09-29
CAUSE OF HOT WAVES
DIRECTOR CHAFFEE CONTRA
 DIcTs A THEORY.
The Moisture from Irrigation of suh-afid Has Nothing to Do
 With Formation of the
 thb Waves. N
Written for The AdyertIser.)


 twritten for The Advertiser)
 Washington Evening Star of the 7th in- stant under the caption Natures Re- Venge, contributed by Mir. E. B. Dunn l or 1;. New York City. and presumably pub usned Tn other papers, is set forth the | theory that irrigation in the West is the | cause Of the phenenaena known as heat | waves. and that on this account the ben. wstghed. The article also claims, or at l | least directly implies. that the great | drought and heat wave. which fingered over the interior of this country so long 1 during the past summer. was either di- l rectiy or indirectly due to mans upset | ting tbs eauillibrium of natures forces l | arid regions of the West. Mir. Dunn weaves a theory, which to those unac- | Quatpted with the meteorological laws of 1 th{s Nentinent, would seem plausible. He | VfssId lead us to believe that the slow l n1oytnR atmospheric depressions that oc- | casionally develop over the lower plateau l region, during the summer months. and 1 which cause q slow movement of heated | aftafroms the south and east. giving pro | longed heat waves over the central and Il middle western districts, are due to the slightly increased atmospheric moisture | over the sub-artd regions, caused by the H extension of irrigation in that section. He claims that this slight increase in at- mospheric moisture is sufficient to gen. crate such mild atmospheric depressions. but insufficient to furnish motive force necessary to start them on their gyratory izatien of superheated air towards the region affected. He concludes his article with the following paragraph:
 ''Tkere is TO doubt but that artificial irrigation has been the means of bring ing into use land which for years has been an idle waste, but Is it not of the ther changes. possibly of the direst ef- feet. may be wrought thereby in the de- velopment of heat waves and-other, at- that the benefits derived from irrigation are greater than the evils which follow in it's train?'
 The article referred to, if not contra dicted. Is calculated to work injustice to the cause of irrigation and to q region | of the country. which, with proper and legitimate encouragement. Is, in my opin- ion. destined to be one of the most pro- ductiye. And while I am not directly or indirectly interested in exploiting the ad- vantases of the sub-arid region. which mans industry is reclaiming from the desert and causing ito bloom as the rose" the article referred to is so pal pably wrong. that 1t should not go un-
 To begin with. the low pressure areas ever the sub-arid region of the West de. pend no more on the moisture over that moisture over the steppes of Siberia Such depressions are entirely dependent upon the outward circulation of air from con theory, one which obtained up to the last five years, that the low pressure area. or storm center, is primal devel- & opment, has. in the light of later scien- tific development, been abandoned. The depresSions, with accompanying wind, rain etc. are secondary effects. In oth- CT words. the low pressure areas. or storm mere appendages to the high barometer areas. The high-barometer areas may be compared to hills of dense air, the run ming down of which by gravitation, es. pecially in the case of two adjacent highs, causes Ryratory lows. or storn centers. to form over the intervening sur face space. This circulation of air from the highs Is downward and outward iron their centers. The circulation from tht opposite sides of the highs towards the intervening space which may be hun dreds, or occasionally over a thousand o miles. starts the gyratory movement that forms the low. while the crowding of tn furface air upward and causes It's mois ture to be condensed by mixture witt the colder air above. thus giving tn rains usually preceding and accompany ing the passage of atmospheric depres sions
 An examination of the weather charts of thls country for the past twenty year will show that the development of tn slow-moving depressions, or those 0 slight energy, over the sub-arid region of the west is no more frequent in re cent years than before any concerto, movement towards irrigation in that re zion. It will also demonstrate that ther develop ment of such derresEions and the exten sion of irrigation. In fact accurate hy grometric observations by the Weathe Bureau for long period of years .clearl! shows that the extension of irrigation ha had no appreciable effect on the atmos phertc moisture of the sub-arid region of the West. In view of these facts, will be seen that the theory advanced fl the article above referred to Is erroneous for. in order to cause the change in storr development claimed by MT. Dunn, tn Fl RI0V fVN nkw~ -.t. twx kk. region would nece ssarily be great
 The slow moving depression that cause or accompanied the remarkable hea wave of last summer was not due to an
 increase or lack of moisture over the sub arid region of the West, but to the pecu liar position and structure of high-pres sure areas, which were so far apart an
 or such mild type as to cause yer slow circulation and consequent stagna tion and superheating of the air over tn interior. It is quite possible that the in auction of the ocean into the Sahar desert might seriously alter the climati conditions of that portion of the world as claimed in article under discussion. bu It IS merely surmise and other objec tions to such change are fully as ser
 ous However, it is not sound reason ing to compare the climatic effect exert ed by such water surface as woul cover the Sahara, with the comparativ cobWeb.like water surface provided b the irrigation system now in force
 The theory advanced by Mir. Dunn
 discredited by the entire scientific sta
 or the Weather Bureau. It is not onl calculated to work a serious injury to
 section. the development of which wi add materially to the welfare of the coul try as a whole, and particularly to tn commercial advantage of the Gulf State
 but savors too much of the let-Wel enough-aione school of thought thf marked the dark ages: Certainly one ( mote knowledge that will accelerate th wheels Of commerce and industry. Sur, lY there Is no more praiseworthy wor than that of the engineers who are GoI, ing the problems of irrigation in the sul
 arid region Of this country, for to mai two olades or grass grow where one gre
 Of man. F. P. Chaffee.