Northern-hemisphere sentence example
The tertiary era opens with a climate in which during the Eocene period something like existing tropical conditions must have obtained in the northern hemisphere.
The evidence which has thus been briefly summarized, points unmistakably to the conclusion that existing vegetation originated in the northern hemisphere and under climatic conditions corresponding to what would now be termed sub-tropical.
Little confidence can, however, be placed in the identification of Proteaceous or, indeed, of any distinctively Australian plants in Tertiary deposits in the northern hemisphere.
The whole story points to a general distribution of flowering plants from the northern hemisphere southwards.
Here we may probably find the lowest temperatures of the northern hemisphere.Advertisement
As a rule the genera of the northern hemisphere differ from those of the southern.
This is part of the great temperate flora which, with locally individualized species, but often with identical genera, ranges over the whole of the temperate zone of the northern hemisphere.
They are called vernal and autumnal respectively, from the relation of the corresponding times to the seasons of the northern hemisphere.
The gradual elevation of the whole of northern Russia and Siberia, and the consequent draining of the marshes, is one of these deeper-seated, ampler causes; another is the desiccation of the lakes all over the northern hemisphere.
It is not till the early Eocene that mammals become a dominant type in the northern hemisphere.Advertisement
The remaining marsupials (namely the families Didelphyidae and Epanorthidae) are American, and mainly South and Central American at the present day; although during the early part of the Tertiary period representatives of the first-named family ranged all over the northern hemisphere.
Lastly, among the Duplicidentata, the picas (Ochotonidae or Lagomyidae) form a group confined to the colder or mountainous regions of the northern hemisphere.
The birthplace of the group was evidently in the northern hemisphere - possibly in east Central Asia.
The now waning group of Perissodactyla would appear to have originally been a northern one, as all the three existing families, rhinoceroses (Rhinocerotidae), tapirs (Tapiridae), and horses (Equidae), are well represented in the Tertiaries of both halves of the northern hemisphere.
The sketch given above extends, for the later periods, to the vegetation of the northern hemisphere only.Advertisement
In Australia, South America and South Africa a few plants have been found which agree closely with Lower Carboniferous types of the northern hemisphere.
This flora appears to have abruptly succeeded an older flora in Australia and elsewhere, which was precisely similar to that of Lower Carboniferous age in the northern hemisphere.
This continental area has been described as " Gondwana Land," a tract of enormous extent occupying an area, part of which has since given place to a southern ocean, while detached masses persist as portions of more modern continents, which have enabled us to read in their fossil plants and ice-scratched boulders the records of a lost continent in which the Mesozoic vegetation of the northern hemisphere had its birth.
The Coal-bearing strata which occupy a considerable area in China (Map A, II.), contain abundant samples of a vegetation which appears to have agreed in their main features with the Permo-Carboniferous floras of the northern hemisphere.
Amalitzky found in beds of Upper Permian age in the province of Vologda (Russia) (Map A, V.) species of Glossopteris and Naeggerathiopsis typical members of the Glossopteris flora, associated with species of the ferns Taeniopteris, Callipteris and Sphenopteris, a striking instance of a commingling in the far north of the northern hemisphere Permian species with migrants from " Gondwana Land."Advertisement
The Permo - Carboniferous beds of South Africa, India and Australia are succeeded by other plant-bearing strata, containing numerous species agreeing closely with members of the Rhaetic and Jurassic floras of the northern hemisphere.
There is, however, a marked difference, as regards the floras as a whole, between the uppermost Palaeozoic flora of the northern hemisphere and such species as have been recorded from Lower Triassic beds.
This apparently rapid alteration in the character of the southern vegetation took place at an earlier period than that which witnessed the transformation in the northern hemisphere.
The difference between the Glossopteris flora and those which have left traces in the Upper Gondwana rocks of India, in the Wianamatta and Hawkesbury beds of Australia, and in the Stormberg series of South Africa is much less marked than that between the PermoCarboniferous flora of the northern hemisphere and the succeeding Mesozoic vegetation.
We cannot yet say, however, that the deposits are exactly contemporaneous, and the great climatic variations that have taken place in the northern hemisphere during the existence of our living flora should make us hesitate to correlate too minutely from the evidence of plants alone.Advertisement
He considers the flora to be the most tropical of any that has so far been studied in the northern hemisphere.
Mesohippus and Miohippus are connected with the earliest and most primitive mammal which it is possible to include in the family Equidae by means of Epihippus of the Uinta or Upper Eocene of North America, and Pachynolophus, or Orohippus, of the Middle and Lower Eocene of both halves of the northern hemisphere.
And Figure 18 shows that GW, represented by a northern hemisphere temperature anomaly, is an important factor in the high annual CET values since 1988.
The ship needs to go due south in the northern hemisphere.
The winch hauling the rock uses the northern hemisphere 's largest electric motor - 7000 hp.Advertisement
For many years schools in the northern hemisphere have invested large sums in ICT suites.
During the colder phases, large ice sheets formed over the northern hemisphere land masses.
The convection electric field during this interval is measured in the high-latitude ionosphere using the northern hemisphere SuperDARN HF radar network.
Excellent coverage of the entire dayside high-latitude ionosphere was achieved by all of the northern hemisphere SuperDARN radars.
There are approximately 400 species of deciduous and evergreen primulas mainly from the Northern hemisphere.Advertisement
The peak of northern hemisphere whaling was in 1842 - at that time there were 594 American whalers.
If mountains serve as barriers which arrest the migration of the vegetation at their base, their upper levels and summits afford lines of communication by which the floras of colder regions In the northern hemisphere can obtain a southern extension even across the tropics.
In the winter in the northern hemisphere the sun rises in the southeast and stays low in the sky, setting in the southwest.
Permafrost, which is solid, frozen soil, constitutes about 25 percent of the land area in the Northern Hemisphere.
Greenhouses are mostly a northern hemisphere phenomenon.Advertisement
These suits are cut far more daringly than many women in the Northern Hemisphere might usually consider wearing, even in sunny California.
The fact that Jag is in Australia creates a convenient situation for any last minute shopper, because the seasons run opposite to the northern hemisphere.
The common attitude toward mini bikinis in the Northern hemisphere is generally a conservative one.
A celebration around the winter solstice was a common practice throughout the northern hemisphere for centuries, but it has not always been a Christmas holiday.
However, scientists are quick to point out that when the northern hemisphere is in the constellation of Sagittarius, this may occur.Advertisement
The constellation itself can be seen in the warm seasons in the Northern hemisphere and in the cold seasons in the Southern hemisphere, and it's positioned between 80 and -80 degrees.
For example, it was found that the shadow of an upright stick or stone varied from day to day, because, as we have already noticed, the sun rises farther north in summer in the northern hemisphere than it does in winter.
This Jaeger Lecoultre Atmos also has a new movement that displays northern hemisphere constellations through a large opening.
Most stations in the northern hemisphere have a conspicuous maximum at midsummer with little thunder in winter.
In a region so extensive very great varieties of climate are naturally to be expected, but it may be stated as a general law that the climate of Australia is milder than that of corresponding lands in the northern hemisphere.Advertisement
The Glossopteris flora gradually spread to the northern hemisphere and intermingled with the later Palaeozoic flora which still persisted.
The field of evolution has now been transferred to the northern hemisphere.
The typical genus Lilium and Fritillaria are widely distributed in the temperate regions of the northern hemisphere.
Half of this basin lies deeper than 2750 fathoms, and the greater part of it belongs to the northern hemisphere.
Further, all water particles when moving undergo a deviation from a straight path due to the forces set up by the rotation of the earth deflecting them towards the right as they move in the northern hemisphere and towards the left in the southern.
In the southern countries coal-production is insignificant compared with that in the northern hemisphere.
It is displayed to-day among the antelopes and to a limited degree among the zebras and rhinoceroses of Africa, a continent which exhibits a survival of the Miocene and Pliocene conditions of the northern hemisphere.
That these animals were widely distributed in former times is proved by their occurrence at the present day in palaeozoic fossiliferous strata both of the northern hemisphere and of Australia; and despite the fact that their remains have not been found in rocks of the Mesozoic or Kainozoic epochs, it was conceived to be possible that living specimens might be dredged from the sea-floor during the exploration of the ocean depths undertaken by the "Challenger" expedition.
Canes Venatici ("The Hounds," or "the greyhounds"), in astronomy, a constellation of the northern hemisphere named by Hevelius in 1690, who compiled it from the stars between the older asterisms Ursa Major, Bodtes and Coma Berenices.
The general direction of these disturbances in the northern hemisphere is an attraction of the north-seeking end of the needle; in the southern hemisphere, its repulsion.
Thus we have in the northern hemisphere the Sahara desert, the deserts of Arabia, Iran, Turan, Takla Makan and Gobi, and the desert regions of the Great Basin in North America; and in the southern hemisphere the Kalahari desert in Africa, the desert of Australia, and the desert of Atacama in South America.
Even in the northern hemisphere there are large areas in the Arctic about which little is known.
Fritz (2) has, however, drawn a series of curves which are believed to give a good general idea of the relative frequency of aurora throughout the northern hemisphere.
In the northern hemisphere to the south of the zone of greatest frequency, the part of the sky in which aurora most generally appears is the magnetic north.
In spite of the existence of a number of more or less well-marked geographical forms, reindeer from all parts of the northern hemisphere present such a marked similarity that it seems preferable to regard them as all belonging to a single widespread species, of which most of the characters will be the same as those of the genus.
It is cosmopolitan in distribution, but the majority of the species are confined to the temperate and colder parts of the northern hemisphere and many are arctic or alpine.