1896 Arrhenius (1119300), страница 7
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K 1 ----1"5). Then we at firstsuppose W unaltered and seek the new value of p, say Pl, thatis valid on this supposition. Next we have to seek ~, whichcorresponds to plKa (l'5pl) and plW. From formula (3) wecan then easily calculate the alteration (t) (here increase) inthe temperature at the given place which will accompany thevariation of fl from t9 to/91.
In consequence of the variation(t) in the temperature, W must also undergo a variation. Asthe relative humidity does not vary much, unless the distribution of land and water changes (see table 8 of my originalmemoir), I have supposed that this quantity remains constant,and thereby determined the new value W 1 of W. A freshapproximation gives in most cases values of W 1 and fi~l whichmay be regarded as definitive. In this way, therefore, weget the variation of temperature as soon as we know timactual temperature and humidity at the given place.In order to obtain values for the temperature for the wholeear,h, I have calculated from Dr.
Buehan's charts of the meantemperature at diflbrent places in every month* the meantemperature in every district that is contained between twoparallels differing by 10 and two meridians differing by 20degrees, (e. y., between 0 ° and 10° N. and 160° and 180° W.).The humidity has not as yet been sufficiently examined forthe whole earth ; and I have therefore collected a great manymeasurements of the relative humidity at different places(about 780) on the earth and marked them down in maps ofthe world, and thereafter estimated the mean values tbr everydistrict. These quantities [ have tabulated for the four seasons~Dec.-]?eb., March-May, Jane-Aug., and Sept.-Nov. Thedetailed table and the observations used are to be found inmy original memoir : here I reproduce only the mean valuesfor every tenth parallel (Table VI.).* Buchan : Report on the Scientific Results of the Voyageof H.M.S.Challenger,' Physics and Chemistry, vol.
it., 1889.+25"4+24"0+25'5+25"5 J +25"8+25"5+ 2 4 " 0 [ +2O'8+20"5+15"2+ 9"5+ 2"0+23"2{-25"7+24"9+22"4+17"5+11"6+ 5'3--+0"45"9+11"3+16"4+26"8+21"5+ 17"0+26"0+21"8+13"5+ 8"4 ! +14"5+0'2+ 7"5+18"71"4+-- 8"84.7'8----11"2--21"1•6'07"0+ 1"2--~t2+23"2+19'7+14"5+ 8.7+ 2-1+19"3+14-2+ 8-2+ 1"6+25"1+25"0+23"1+25'5+25"4+ 2 5 '9+25"5+21"9+23'0+16'6 I +15"3+ 9"7r + 8"7+ 2"2--0'2:Mean Temperature.8179818380797575788181797873747768687374817173788386--838O80808282787O67697677797975778081777371768084:Mean Relative Humidity.8178"577"278"58179"575"570"569"77478"2825"748"3411'114"818"019"417"715'38"826"2217"919"94"467"0810"414"0--5'948"11] "11 7 " 1 14'619"018"91 7 " 0 19"617"18"63 13"45"98 10"83"822"141036 ' 1 2 6 36"533"862'221'15I6"639"6[3'016'018"319"316'815'010"137'164'72"84o~6"999"8L3"2L6'4L8'7L8'9L7'213"89"76"954"93 '09Mean Absolute Humidity.VI.--Mean Temperature, Relative and Absolute Humidity*.From the figures for temperature and ~elative humidity I have calculated the absolato hmnidity in g, ams per cubic metre.-60-50-40-30-20-101C2~3C4d5C6C7C,xJTABLE¢%?c~in the Air upon the Temperature of the Ground.265By means of those values, I have calculated the meanalteration of temperature that would follow if' the quantity ofcarbonic acid varied from its present mean value (1(=1) toanother, viz.
to 1(----0"67, 1"5, 2, 2"5, and 3 respectively. Thiscalculation is made for every tenth parallel, and separatelyfor the four seasons of the y~ear. The variation is given inTable VII.A glance at this Table shows that the influence is nearlythe same over the whole earth. The influence has a minimumnear the equator, and increases from this to a fiat maximumthat lies the further from the equator the higher the quantityof carbonic acid in the air. For K=0"67 the maximmnefi~et liesabout the 40th parallel, for 1(=1"5 on the 50tb,for K = 2 on the 60th, and for higher 1(-values above the70th parallel.
The influence is in general greater in thewinter than in the summer, except in the case of the partsthat lie between the maximum and the pole. The influencewill also be greater the higher the value of v, that is ingeneral somewhat greater for land than for ocean. On accountof the nebulosity of the Southern hemisphere, the effect willbe less there than in the ~orthern hemisphere. An increasein the quantity of carbonic acid will of course diminish thedifference in temperature between day and night. A veryimportant secondary elevation of the effect will be producedin those places that alter their albedo by the extension orregression of the snow-covering (see p.
257), and this secondaryeffect will probably remove the maximum effect from lowerparallels to the neighbourhood of the poles *It must be remembered that the above calculations arefound by interpolation from Langley's numbers for the valuesK=0"67 and K=1"5, and that the other numbers must beregarded as extrapolated. The use of Pouillet's formulamakes the values for K = 0 ' 6 7 probably a little too small,those for K = l ' 5 a little too great. This is also withoutdoub~ the case for the extrapolated values, which correspondto higher values of K.We may now inquire how great must the variation of thecarbonic acid in the atmosphere be to cause a given change ofthe temperature. The answer may be found by interpolation in Table VII.
To facilitate such an inquiry, we maymake a simple observation. If the quantity of carbonic aciddecreases from i to 0"67, the fall of temperature is nearly thesame as the increase of temperature if this quantity augments1"5. And to get a new increase of this o~'der of magnitude(3°'4)~ it will be necessary to alter the quantity of carbonicacid fill it reaches a value nearly midway between 2 and 2"5.See Addendum, p.
275.--60-50-40--30-20-10010203040506070•--3"2--3"4--3"3--3"1--3"1--3"0--3"1--3"1--3"3--3"4--3"2--3"0--2"9I.~IVII.--Variation"-3'3--3'4--3"3--3"2--3"1--3"0--3"0-3"1-3"2-3"4--3"3--3"2--3"0~~----3"3--3"4--3"3-32-3'1--3"0-3'0--3'1-3"2-3"3--3'4--3"4,~~=-3'0~3"4-3"3~- 3 " 4 --3"3~---3"2 --3"2-3"0 --3'0~l--3"1 -3"1I-3'0-3"1 --3"0--3'11--3"17--3"3 --3'3~-3"4 --3'3--3"3 --3'22--3'1 --3"15gCarbonic Acid =0'67.T~SECarbonic Acid--- 2"0.3"2 3'5 3"473"~ 5"65"03'8 3'7 - ----3"6 3"7 3'8 3'7 3"73"6"05'83'4 3"5 3"7 3"5 3'5~3'~ 5"53'2 3"2 3'4 3"3 3'~3'27 5'23'2 3"2 3"2 3'2 3'~3'23'1 3"1 3'2 3"2 3'153'i4"93'2 3'2 3"1 3'1 3'153'i5-03'5 3"2 3-1 3"2 3"253"~ 5'23'5 3'33'7 3"6 3'3 3"5 3"523"! 6'03"65 6'13'7 3"8 3"4 3"7 3"(3'62 6"13"4 3"7 3"6 3'8 3'(3"52 6"03"3 3'4 3'8 3"6 3"~OCarbonic Acid = 1"5.~'0~'9F'23'8}'6;-43"4;-6T'OT'6['93"03"0Carbonic Acid=2"5.9'5--9'2 [ 9'48"7 9"18'1 8"67"5 8"07 - 3 i 7.47"3~l 7"27"51 7"28'31 7"59"01 8'29"41 8"69"51 8"99'3 t 9"4Carbonic Acid=3'0.of Temperature caused bV a given Variation of Carbonic Acid.'~,~~-~~~5"2"0"~in the Air upon the Temperature of the Grouud.267Thus if the quantity of carbonic acid increases in geometrioprogression, the augmentation of the temperature will increasenearly in arithmetic progression.
This rule--which naturallyholds good only in the part investigated--will be useful for thefollowing summary estimations.5. Geological Consequences.I should certainly not have undertaken these tedious calculations if an extraordinary interest had not been connectedwith them. In the Physical Society of Stockholm there havebeen occasionally very lively discussions on the probablecauses of the Ice Age; and these discussions have, in myopinion, led to the conclusion that there exists as yet no satisfactory hypothesis that could explain how the climatic conditionsfor an ice age could be realized in so short a time as that whichhas elapsed from the days of the glacial epoch.
The commonview hitherto has been that the earth has cooled in the lapse oftime; and if one did not know that the reverse has been thecase~ one would certainly asserf that this cooling must go oncontinuously. Conversations with my friend and colleagueProfessor HSgbom~ together wish the discussions abovereferred to, led me to make a preliminary estimate of theprobable effect of a variation of the atmospheric carbonicacid on the temperature of the earth.
As this estimation ledto the belief that one might in this way probably find anexplanation for temperature variations of 5°-10 ° C, I workedout the calculation more in detail~ and lay it now before thepublic and the critics.From geological researches the fact is ~ell establishedthat in ~ertiary times there existed a vegetation and ananimal life in the temperate and arctic zones that must havebeen conditioned by a much higher temperature than thepresent in the same regions *. The temperature in the arcticzones appears to have exceeded the present temperatureby about 8 or 9 degrees.
To this genial time t h e ice agosucceeded~ and this was one or more times interrupted byinterglacial periods with a climate of about the same characteras the present~ sometimes even milder. When the ice agehad its greatest extent~ the countries that now enjoy thehighest civilization were covered with ice.
This was thecase with Ireland, Britain (except a small part in the south),Holland, Denmark, Sweden and Norway, Russia (to Kiev,* For details vf. Neumayr~ .Erdgesvhivhte, B~. 2~ Leipzig, 1887; andGeikie, ' The Great Ice-Age,' 3rd ed. London~ 1894 ; l~athorst. Jord~shistoria, p.
989, Stockholm, 1894.268Prof. S. Arrhenius on the Influence of Carbo'Jdv AcidOrel, and Nijni Novgorod), Germany and Austria (to theHarz, Erz-Gebirge, Dresden, and Cracow). At the sametime an ice-cap from the AIps covered Switzerland, parts ofFrance, Bavaria south of the Danube, the Tyrol, Styria, andother Austrian countries, and descended into the northern partof Italy. Simultaneously, too, North America wascovered withice on the west coast to the 47th parallel, on the east coast tothe 40th, and in the central part to the 37th (confluence ofthe Mississippi and Ohio rivers).
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