CHAPTER XIX. Climate and History

CLIMATE AND HISTORY

It is a remarkable fact in human history that civilization began in regions which are at present inhabited chiefly by backward races, and the centres of progress have shifted from one country to another with the passage of time. Many accidental factors—position on trade-routes, possession of special mineral advantages, and so on, have undoubtedly played a part in this, but it will not be difficult to show that climatic fluctuations have also had their share.

A brilliant study of Ellsworth Huntington has shown that there are certain optimum conditions of climate which are most suitable for efficient work. These conditions, which were determined by an analysis of the output of work in American factories, were then found to be just those which prevail in the most progressive regions of the globe, which are located in the temperate storm-belts, and it is shown in certain instances that fluctuations in the position of this storm-belt coincided with fluctuations in the centres of civilization. A few additional examples of this may be given.

The beginnings of civilization may reasonably be placed with the transition from the Palæolithic to the Neolithic type, a transition which involved much more than just the polishing of stone weapons. It involved also the beginnings of agriculture, crude pottery, and later, the domestication of animals. One of the earliest Neolithic cities known is probably that of Anau, near Askabad in Transcaspia, excavated by Pumpelly in 1904. From the thickness of the accumulated debris the date of first settlement is placed at or before 8000 B.C., i.e. 10,000 years ago, or during the period which in Europe is assigned to the concluding stages of the Wurm glaciation. Pumpelly’s time-estimates are based on careful comparison with accumulations in Merv and other cities. At present the mean annual rainfall in that part of Turkestan is below ten inches a year, and the country is practically desert, and is entirely unfitted for agriculture. But with the remains of the ice-sheet still over Scandinavia and depressions following a more southerly course along the Mediterranean basin and into southern Asia, the rainfall was considerably heavier, and the climate in general was more suited to a progressive race. At the outset we find this Neolithic race living in rectangular houses built of uniform sun-dried bricks; they were skilful potters, cultivating cereals, but at first without domestic animals.

The beginning of Neolithic civilization in Crete is placed by Evans at about 12000 B.C., while on the basis of excavations by de Morgan at Susa in Persia, Montelius places the origin of Neolithic culture in this part of Asia as early as about 18000 B.C. At Susa the deposits are 130 feet thick, and of these the upper 40 feet cover a period of 6000 years.

Thus we see that what may be considered as the great step from savagery to civilization took place while the present centres of progress in Europe and America were still in the Ice Age. At this time the climate of southern Asia must have resembled the present climate of north-west Europe in heavier rainfall and the day-to-day fluctuations of weather—in fact, the districts where civilization began probably had at that time the most stimulating climate in the northern hemisphere.

With the vanishing of the ice-sheets and the setting in of the mild climate of the Maritime phase the Neolithic culture spread rapidly to Europe, and by 2000 B.C. even the Baltic regions were well inhabited, and it is probable that the Aryan race was developing in the Russian steppes. About this time Anau was abandoned owing to increasing aridity.

With the coming of the Bronze Age in western Europe, about 1800 B.C., however, the climate again became colder and rainier, corresponding to the Peat-bog phase or “Classical” rainfall maximum, the deterioration culminating in the Early Iron Age. This period was marked by a great southward spread of the Aryan peoples, and ushered in the Heroic Age of Greece. The races of the Mediterranean, as we have seen, continued to thrive throughout this rainy period, and their power did not diminish until its close, about A.D. 400. This downfall was accelerated if not caused by the pressure of nomad peoples driven out of Asia by the increasing drought. These Asiatic migrations included the great marches of the Tartar hordes and, aided by religious enthusiasm, the conquests of the Moslems.

The early Middle Ages, after the downfall of Rome, appear to have been characterized by a dry warm climate. This was the age of the Vikings, when the Norse races rose to dominance in western Europe, finally invading and occupying large areas of France and Britain, and even extending their power to Sicily. With the increasing cold and wet of the “Mediæval” rainfall maximum came a final burst of Norse migration, which left the homeland poor and scantily populated, and the centre of activity and progress lay once again with the Mediterranean peoples, and especially with Italy and Spain. The Tartar invasions ceased, and against the increasing power of Europe the Moslem wave broke and receded. At the close of this rainy period political dominance again moved north. From that time the fluctuations of climate have been of minor importance, and correspondingly there have been no great shiftings of political power from latitude to latitude.

BIBLIOGRAPHY.

Tyler, J. M. “The New Stone Age in Northern Europe.” London, 1921.

Huntington, Ellsworth, “World Power and Evolution.” New Haven, 1919.

Haddon, A. C., “The wanderings of peoples.” Cambridge University Press, 1919.

APPENDIX

THE FACTORS OF TEMPERATURE

To calculate the probable temperature of January or July at any point, the following procedure should be adopted:

Draw a circle round the point of angular radius ten degrees (i.e. set the compass to cover ten degrees of latitude) and divide this into two halves by a line passing from north to south through the centre. By means of squared tracing paper, or otherwise, measure: (a) the amount of ice in the whole circle; (b) the amount of land in the western half; (c) the amount of land in the eastern half. (a) is expressed as a percentage of the area of the whole circle; (b) and (c) as percentages of the area of a semicircle.

The term “ice” includes ice-sheets such as that of Greenland or Antarctica, and also frozen sea or sea closely covered by pack-ice; the latter figure may vary in different months.

The temperature in January or July is then calculated from the following formula:

Temperature = basal temperature + ice coeff. x per cent. of ice + land west coeff. x per cent. of land to west + land east coeff. x per cent. of land to east.

The basal temperatures and the appropriate coefficients are given in the following table.

In calculating the effect of a given slight change of land and sea distribution, it is not necessary to employ the basal temperature. Instead the equation can be treated as a differential, and the change of temperature due to the change of land and ice calculated from the figures in columns 3 to 5. The figures are given in degrees absolute, 273°0 = 32° F. To convert differences to Fahrenheit, multiply by 1°8.

---------+-------------+----------+-----------+----------- Latitude.| Basal Temp. |Ice Coeff.| Land, | Land, |(Water Zone).| |West Coeff.|East Coeff. ---------+-------------+----------+-----------+----------- Jan. | a. | | | 70 N. | 298.8 | -0.49 | -0.43 | -0.20 60 | 277.4 | -0.07 | -0.31 | -0.01 50 | 276.8 | -0.09 | -0.29 | 0.09 40 | 282.5 | -- | -0.17 | 0.04 30 | 289.6 | -- | -0.08 | 0.03 20 | 294.2 | -- | -0.01 | -0.01 10 | 298.6 | -- | -0.01 | 0.03 0 | 299.3 | -- | 0.01 | 0.00 10 S. | 298.2 | -- | 0.04 | -0.01 20 | 296.2 | -- | 0.07 | 0.00 30 | 293.5 | -- | 0.06 | 0.03 40 | 289.3 | -- | 0.09 | -0.03 | | | | July. | | | | 70 N. | 279.3 | -0.16 | 0.02 | 0.02 60 | 280.7 | -- | -0.01 | 0.11 50 | 285.8 | -- | 0.04 | 0.06 40 | 291.1 | -- | 0.05 | 0.07 30 | 296.8 | -- | 0.08 | -0.01 20 | 297.6 | -- | 0.07 | 0.02 10 | 298.8 | -- | 0.03 | -0.01 0 | 298.6 | -- | 0.02 | -0.01 10 S. | 296.9 | -- | 0.04 | -0.03 20 | 293.1 | -- | 0.02 | -0.02 30 | 288.2 | -- | -0.01 | -0.01 40 | 284.0 | -- | 0.00 | -0.03 ---------+-------------+----------+-----------+-----------

In the case of the calculation of the effect of comparatively slight and irregular changes in land and sea distribution in a limited area, such as those of the Littorina Sea referred to on p. 128, it may be found that a ten-degree circle is too wide an area to employ, the changes from land to sea at one point being nullified by changes from sea to land at another more distant point. In such a case a smaller unit such as a circle of five degrees radius can be employed. As a rough approximation it may be said that the effect of the conversion of a square mile of land into sea, or vice versa, on the temperature of a neighbouring point is inversely proportional to its distance. Since the area of a five-degree circle is one-quarter that of a ten-degree circle, while the average distance of the land composing it is one-half, we have to divide our regression coefficients by two in order to fit the new data.

This method was applied to obtain the probable temperature distribution on the shores of the Littorina Sea at its maximum extension, and gave results which agreed remarkably well with those calculated by geologists from the animal and plant life of the time.

See London Q. F. R. Meteor. Soc., 43, 1917, pp. 169-171.

INDEX

Acheulian, 52

Aciphylla, 125

Africa, 103, 133, 142

Aftonian, 87

AHLMANN, 51, 61

Alaska, 43, 124

Algonquin, Lake, 123

Alps, dry period, 122 glaciation, 29, 52, 56 retreat stadia, 119

Altai Mountains, 77

Anau, ruins, 163

Ancylus, 120, 127

ANDERSSON, 118, 121

Andes, 98

Antarctica, 114, 133

Anticyclonic circulation, 55

Antipodes Is., 112

Aral Sea, 83

Argentine, 100

Arizona, 94, 150

ARRHENIUS, 19

Artesian water (Australia), 110

Aryans, 164

Asia, 76, 125, 139, 143, 153

Astronomical theory, 17

Atlantic Stage, 126

Atlas Mountains, 69

Australia, 109, 125, 155

Balearic Is., 70

Balkans, 69

Baltic Interstadial, 64

Banded clays, 49, 93

Baraba steppes, 121

Barkans, 65

BARRELL, 159

BEDDARD, 115

Belfast, 130

Biloculina, 133

BLYTT, 127

Bonneville, Lake, 93

Brazil, 101

British Isles, 57, 62, 64, 136

BRÖGGER, 129

Bronze Age, 138

BRÜCKNER, 49, 57, 154

Buenos Aires, sand-dunes, 125

Bühlstadium, 119

Calabrian, 68

Cambrian, 33

Campbell Is., 102

Canada, post-glacial, 132

Cape Colony, raised beaches, 133

Carbon dioxide, 19

Carboniferous, 34

Caspian, 83, 143, 153

CHAMBERLIN, 19

Champlain Stage, 123

Chellean, 51

CHERRY, 160

Chile, rainfall fluctuations, 157

China, 81, 139

Chronology, 48, 92

CHUDEAU, 106

Classical Rainfall Maximum, 140

Climatic Record, 132

COLEMAN, 92

Colorado, 94

Continentality, 25

Continental Phase, 120

Continents, movement of, 21

Cordilleran glaciation, 87

Corsica, 69

CRAIG, 72

Cretaceous, 37

Crete, Neolithic, 163

CROLL, 18

Cro-Magnards, 161

Cyrenaica, desiccation, 142

Daun-stadium, 119

DAVID, 110

Dead ice, 132

Denmark, continental phase, 122

Depressions, path of, 47, 60, 71, 122, 139

Devonian, 34

Diluvium, 48

Don Valley, 91

DOUGLASS, 143

Drakensberg Mountains, 103

Drought in Forest Period, 139

Drumkelin Bog, 137

Dunes, fossil, 65 Frisian, 140

Early Iron Age, 141

Earth’s Orbit, eccentricity of, 18

Earthworms, 115

East Anglia, 47, 57

Eccentricity of Earth’s Orbit, 18

Ecuador, 99

Egypt, 72

Eoanthropus, 161

Eocene glaciation, 37

Etosha Pan, 107

Europe, 49, 55, 118, 127, 136, 154

EVANS, 163

Evolution of Man, 155

FAIRGRIEVE, 138

Falkland Is., 97

Fennoscandian Pause, 119

Finiglacial, 118

Finland, post-glacial, 120, 128

Florida, 95

Forest bed, 47, 51 period, 122, 136

Forests, submerged, 137

Formby and Leasowe Beds, 130

Fossil ice, 59, 78

Franz Josef Land, 130

FRECH, 20

FREYDENBERG, 106

Frisian dunes, 140

Fucino, Lago di, 154

Fucus in Spitzbergen, 130

Gable Island, 98

Galaxiidæ, 115

GEER, G. DE, 49, 93, 118

GEIKIE, J., 51, 81

Geographical theory, 22

Geological formations, 31 rhythms, 38

GIBBON, 140

Gibraltar, 69, 70

Gila conglomerate, 95

Glacial anticyclone, 55 stages, 48

Globigerina, 133

Glossopteris, 35

Gondwanaland, 34, 35

Gotiglacial, 118

Graham Land, glaciation, 114

Great Basin, America, 89, 93, 124

Great Lakes, history, 123

Great Salt Lake, 93

Greece, Heroic Age, 164

Greenland, 131, 156

GREGORY, 104

Grimaldi Race, 161

Gschnitz Stadium, 119

Gunz Glaciation, 56

Gunz-Mindel Interglacial, 50, 51, 56

Haplochitonidæ, 115

Hazel, post-glacial extension, 122

HEDLEY, 116

Heidelberg Man, 161

Height and temperature, 26

HILDEBRANDSSON, 157

Himalayas, 81

HOBLEY, 105, 107

Hohokam, 150

HUME, 72

HUMPHREYS, 20

HUNTINGTON, 141, 144, 150, 153, 162

Ice on Danish coasts, 155

Iceland, 125, 156

Illinoian glaciation, 90

Ingo Is., forests, 122

Iowan Glaciation, 90

Ireland, glaciation, 57, 62, 64 Heroic Age, 138

Iroquois, Lake, 123

Isohalines, 127

Japan, 81

Jurassic, 37

Kalahari, 107

Kamchatka, 80

Kansan, 88

Karst flora, 121

Kashmir, 143, 153

Keewatin, 88, 91

KEIDEL, 99

Kenya, 103

Kilimanjaro, 103

Kioga, Lake, 104

Kitchen-midden, 125

Kosciusko, 109

KREICHGAUER, 20

KUPFFER, 121

Labradorean Glaciation, 87, 89, 90

Lahontan, Lake, 93

Lena Valley, 78

LEVERETT, 91, 92

Limestone Agglomerate, 70

Littorina, 128

Loess, 52, 83, 91, 112

Lofoten Islands, 61

Lop-Nor, 83, 153

MACKENNA, 157

Maglemose culture, 125

Malta, 69

Mammoths, frozen, 79

Marsupials, 115

MATHEW, 160

Maumee, Lake, 123

Maya ruins, 151

Mediæval Rainfall Maximum, 164

Medicine Bow Range, 94

Mediterranean, 68, 142

Mesopotamia, Empires, 139

Mexico, culture, 151

MEYER, 99

Micmac Stage, 124

Mindelian Glaciation, 49, 69

Mindel-Riss Interglacial, 50

Miocene, 44

Mombasa, 105

Mono Basin, 94

MONTELIUS, 163

Mousterian Man, 63

MUNTHE, 118

MURGOCI, 66

Murman coast, 130

Najas, 129

Neanderthal Man, 161

NEGRO, 142

Neolithic, 122, 131, 136, 163 migration, 125, 163

Neudeckian, 51

NEUHAUSS, 111

Newfoundland, 87, 90

New Guinea, 111

New Siberian Islands, 78

New South Wales, 125

New Zealand, 111, 125, 133

Ngami, Lake, 107

Niagara, 93, 132

Nile, 72, 119

NORDENSKJOLD, 117

Nordic Race, 125

Norfolkian, 51

North America, 86, 122, 132, 141, 149

North Sea, 56, 61

Norway, 51, 55, 129

Obliquity of Ecliptic, 16, 120

Old Red Sandstone, 34

Optimum of Climate, 127

Ordovician, 33

Pajaritan, 150

Palmyra, 142

Pamirs, 77

Pampean, 100, 125

Patagonia, post-glacial, 133

Patom Highlands, 78

Peat-bog Period, 140

PENCK, 49, 51

Pendulation Theory, 20

Peorian, 91

Permian, 35

Persia, 84, 142

Peru, 99

PETTERSSON, 134, 145

Piedmont ice-sheets, 57, 109

Piltdown Man, 161

Pithecanthropus, 160

Pliocene, 47

Pluvial periods, 71, 140

Poles, motion of, 20, 40

Pre-Cambrian Glaciation, 33

Proterozoic Glaciation, 32

Pueblo ruins, 150

Pulse of Asia, 153

PUMPELLY, 84, 163

Pyrenees, 57

Quaternary Ice Age, 47

Ragunda, Lake, 49 moraines, 121

REID, 138

Retreat of the Ice, 49

Riss Glaciation, 49, 61

Riss-Wurm Interglacial, 50, 53

Rixdorf, 62

RODGERS, 133

Romania, 66

Ruwenzori, 103

Sagas, 141, 146

Sahara, 74, 105

Sangamon, 90

Scania, 49

SCHMIDT, 53

Scotland, 57, 61, 64

Scrobicularia Zone, 130

Selsey, 58

Sequoia, 143

Shell-banks, 47, 56

Siberia, 78

Sicilian, 70

Sierra Nevada, 93, 94

SIEVERS, 99

Silurian, 33

Skærumhede, 63

Slugs, 115

SMITH, ELLIOTT, 159

Solar radiation, 15

South America, 97, 125, 132, 157

South Georgia, 97

South Orkneys, 114

SPITALER, 18

Spitzbergen, 80, 130

Stanovoi Mountains, 79

Steppe climate, 53

Stone rivers, 98

Submerged forests, 137

Suess, Lake, 104

Sunspots, 145

Susa, Neolithic, 163

SVEN HEDIN, 84

Sweden, 49, 56, 118

Syria, 72

Tapes, 129

Tasmania, 109

Tchad, 106

Tertiary, 42, 116

Thracia Zone, 131

Tian-Shan Mountains, 77

Tibet, 82

Tidal friction, 39

Tide-generating force, 134, 145

Tierra del Fuego, 97, 133

Tillite, 32

Titicaca, Lake, 101

Toronto Stage, 91

Trapa, 129

Trasimeno, Lake, 154

Tree-rings and rainfall, 143

Turbarian, 140

Triassic, 37

TYNDALL, 19

Uinta Mountains, 94

Unio in Niagara, 132

Ural Mountains, 57

Venezuela, 100

Verkhoiansk Mountains, 79

Victoria Nyanza, 104

Vikings, 164

Volcanic dust, 16, 20

VOLLOSSOVITSCH, 79

Wales, 57, 64

Warren, Lake, 123

Wasatch Mountains, 93, 94

WAYLAND, 104

WEGENER, 20, 34

WERNERT, 53

White Sea, 130

Wine harvest, 155

Winters, severe, 155

Wisconsin Glaciation, 91, 92

WOLF, 145

Wurm Glaciation, 48

Yarmouth Stage, 88

Yoldia Sea, 50, 124

Yucatan, 151

Yukon, 124

Printed in Great Britain by Jarrold & Sons, Ltd., Norwich.

FOOTNOTES:

By this term we shall in future understand only that part of it which is responsible for thermal effects.

If the figure of the earth is adjusted to its speed of rotation before the development of ice-sheets, the latter renders it too prolate, and there will be a tendency for readjustment by the transference of mass towards the equator.

This has been the subject of much discussion recently. For a summary see Science Progress, 17, 1922, October, p. 233.

Leverett, F. (see Bibliography).

See reference to Antevs in this connexion.

“The pulse of Asia,” p. 356. See also a new work by E. Huntington, entitled: “Climatic changes.”

“Climatic variations in historic and prehistoric time.”

“Sur le prétendu changement du climat européen en temps historique.”

Or lemur-like ancestor. There is evidence to show that man’s ancestor was a nocturnal animal, whose food supply was governed by the phases of the moon.

“Scientific monthly,” New York, 4, 1917, pp. 16-26.

“Science progress,” 15, 1920, p. 74.

“Climate and evolution.”

“Civilization and climate.”

TRANSCRIBER’S NOTE

Obvious typographical errors and punctuation errors have been corrected after careful comparison with other occurrences within the text and consultation of external sources.

Some hyphens in words have been silently removed, some added, when a predominant preference was found in the original book.

Except for those changes noted below, all misspellings in the text, and inconsistent or archaic usage, have been retained.

Pg 64: ‘powerful conviction’ replaced by ‘powerful convection. Pg 97: ‘and Tierra del Fuega’ replaced by ‘and Tierra del Fuego’. Pg 103: ‘Drakenberge Mountains’ replaced by ‘Drakensberg Mountains’. Pg 150: ‘modern Pueblas who’ replaced by ‘modern Pueblos who’. Pg 166: ‘coffiecients are’ replaced by ‘coefficients are’.