(See also maps, Plates 5, 6, and 9; and map of Isobars, Plate 14.)

The ratio of resultant is less in spring than at other seasons. This is caused by the great increase of pressure in the Polar region, as has been shown before. N. E. winds are oftener experienced in spring than at other seasons.

I must further remark that the character of the winds in Great Britain and the adjoining islands is strictly oceanic i. e., such as would be found in the same latitudes on the oceans. The relative position of the land and sea have scarcely any influence. This is due, first, to the great difference of pressure between north and south, and the great strength of the winds which is the result, so that local causes are comparatively unimportant; second, to the small extent of land, which, being besides pervaded by the influence of the sea, is neither much more heated in summer, nor much more cooled in winter than the surrounding ocean. (See Plates 9 and 12.)

The conditions of the Scandinavian Peninsula are very different. It is by itself a large body of land. Besides this, the high mountain chain rising near its western coast is a great barrier to the influence of the Atlantic Ocean on the interior. The result is a much more continental climate than could be expected from a country so near to the Atlantic Ocean.

In many respects the physical features resemble those of Alaska, where the contrast between the mild, equable climate of the coast and the excessive seasons of the interior is equally great. The winds of the Scandinavian Peninsula are shown in the two following tables; in the first by percentages, and in the second in direction,

direction.

Mean

Winter.

resultant.

In winter the whole coast of Norway has monsoon winds, blowing from the land to the sea, they are N. and N. E. at Christiania, S. E. at Christiansund, Bossekop and Hammerfest, and S. W. at Vardöe. In summer the conditions are reversed. This was shown some years ago by the best authority in these matters, Prof. H. Mohn.1 He is of the opinion that the winds are deflected about 90° to the right of the direction they would have if they blew directly from the land in winter and from the sea in summer.

It must, however, be observed that in this result the number of observations alone is taken into account. The storms on the Atlantic coast of Norway are very violent, and the winds during their prevalence mostly S. and W. A south wind should prevail in Norway, taking into account the strength of winds and aside from local influences.

The high station of Dovre, in the interior, has largely prevailing S. winds. In this we see the influence of the high pressure to the S. and in the interior of the continent and of low pressure on the ocean to the W. and N. (See Plates 9 and 14.) In northern Norway the winds are variable in summer and decidedly from the S. in the winter. In the latter season the general distribution of pressure in the

1 Oversigt of Norges Klimatologi. See also Norsk Meteorologisk Aarbog.

Winter.

surrounding countries, and the local monsoon influence, act in the same direction, as the land is to the S., the ocean to the N. In summer they counteract one another. Besides this, the character of the Arctic Ocean must be considered. It is traversed by a warm current, and at no time of the year do icebergs approach the coast of Norway. Even in the summer the temperature of its waters is higher than that of the air on the land. On such a sea a low pressure must prevail, and its monsoonproducing influence in summer cannot be compared with that of an ice-laden sea. In northern Sweden the wind has also a southerly direction. The Gulf of Bothnia has but very little influence, being a small body of water and frozen to a great extent in winter, otherwise we would have northerly winds in winter, while the Arctic Ocean attracts the air so strongly that no other influence is to be considered in comparison. The S. winds of summer may be partly sea-winds.

In southern Sweden the winds are S. W. in the winter, and W. in summer. The influence of the low pressure in the interior of the continent begins to be felt here at the latter season. (See Plates 5, 6, 9 and 14.)

Bear Island, between Norway and Spitzbergen, lies N. of the warm current of the Gulf-stream. Accordingly the Polar current (E.) is largely prevailing in winter, while the winds of summer are more variable. Bear Island has a position very like that of Iceland, yet it is more clearly north of the warm ocean-current with its low pressure. Besides, at times the island is surrounded by extensive ice-fields, and the temperature sometimes sinks very low over them, and consequently pressure increases.

Iceland and Bear Island are important stations, proving the existence of prevailing polar winds N., N. E., E. in the waters north of Europe, and north of the warm current of the Gulf-stream, while all stations in the extreme north on the continent of Europe still have equatorial winds (S., S. W., W.). Thus, the division line between the two systems of winds is proved to be the belt of low pressure along the warm ocean-current. (See maps, Plates 5, 6 and 7.)

The winds of Spitzbergen seem to be more influenced by the relative position of land and sea than those of Bear Island. In winter they blow from the land, as is seen by the observations of Mossel-Bay, on the N. shore of the principal island, and Ice-Fjord on the S. shore of the same.

CENTRAL EUROPE.

Southwesterly and westerly winds prevail also in the rest of western Europe, that is, Denmark, Germany, the Netherlands, Belgium and Northern France. This is evident from the following table of percentages:

2

This is still a region of the undisputed prevalence of westerly winds. What may be noticed in S. Sweden is seen here in nearly all the stations: the winds in summer incline somewhat to the N. W. Kämtz was the first to notice the opposite course taken by the N. W. and the S. E. winds on the continent of Europe, the first being most frequent in summer, the last in the winter. This is caused by the contrasts of temperature and pressure of the interior of the continent, and of the Atlantic Ocean, the influence of the land being conspicuous in winter, that of the ocean in summer. The S. W. winds are most numerous in Belgium and Holland, while this is less the case in southern Germany, where the W. winds prevail. This is partly caused by the influence of the Alps, which do not give free access to S. W. winds, while those from the west reach Germany without impediment. The direction of the winds in this region is given in the following table:—

1 Result of forty years' observations, calculated by Haeghens, Annuaire de la Société Méteorologique de France.

Ratio of
resultant.

Mean
direction.

Ratio of
resultant.

Mean
direction.

Ratio of

resultant.

S. W.

W.

N. W.

N. E.

Winter.

S. E.

S.

S. W.

W.

N. W.

(See also Plate 9.)

The N. W. winds of spring in most of the stations of Western Europe must be noticed, especially in stations near the coast of the Atlantic Ocean or the North Sea. The mean direction of the wind in summer is more northerly than in winter.

Central and Southern France, Northern Italy, Switzerland, and the western provinces of Austria are a border-land between two different systems of winds, southerly or westerly prevailing in the N. of this region, and northerly in the S. Still we must expect to find the winds very much influenced by locality in such mountainous countries. The following are the percentages of the winds in the countries mentioned.

In Southern France N. W. and N. winds may be said to predominate, and not only are they the most frequent but also the strongest. They are known under the name of Mistral. As early as in 1861 Renou traced the isobaric lines of France, and showed that the highest pressure was found in the centre of the country near Limoges. Reduced to sea-level it amounted to 764 millimetres (30.08 inches), to the south it is less. In winter the temperature along the coast from Marseilles to Livorno is much higher than in the surrounding country, this being probably the cause of the lower pressure. (See Plate 14.) In summer the stony, treeless plains on the lower Rhone are so very much heated, as to attract the air of the surrounding country. It comes from the Atlantic, up the valley of the Garonne, as a N. W. wind, and descends towards the Mediterranean near Cette. It will be seen from the table that S. W. France has prevailing N. W. winds only in summer, while in winter southerly winds are frequent.

1 "Annuaire de la Société Méteorologique de France," of that year.

N.

N. E.

E.

S. E.

S.

S. W.

Ꮃ .

N. W.