Search results
Results from the WOW.Com Content Network
The polar of the closed convex cone C is the closed convex cone C o, and vice versa. For a set C in X , the polar cone of C is the set [ 4 ] C o = { y ∈ X ∗ : y , x ≤ 0 ∀ x ∈ C } . {\displaystyle C^{o}=\left\{y\in X^{*}:\langle y,x\rangle \leq 0\quad \forall x\in C\right\}.}
Visualization of the ice and snow covering Earth's northern and southern polar regions Northern Hemisphere permafrost (permanently frozen ground) in purple. The polar regions, also called the frigid zones or polar zones, of Earth are Earth's polar ice caps, the regions of the planet that surround its geographical poles (the North and South Poles), lying within the polar circles.
The Hadley cell is a closed circulation loop which begins at the equator. There, moist air is warmed by the Earth's surface, decreases in density and rises. A similar air mass rising on the other side of the equator forces those rising air masses to move poleward. The rising air creates a low pressure zone near the equator.
Relationship of Earth's axial tilt (ε) to the tropical and polar circles. The Arctic Circle is the southernmost latitude in the Northern Hemisphere at which the centre of the Sun can remain continuously above or below the horizon for twenty-four hours; as a result, at least once each year at any location within the Arctic Circle the centre of the Sun is visible at local midnight, and at least ...
Solar radiation has a lower intensity in polar regions because the angle at which it hits the earth is not as direct as at the equator. Another effect is that sunlight has to go through more atmosphere to reach the ground. [1] The polar climate regions are characterized by a lack of warm summers but with varying winters. Every month a polar ...
For premium support please call: 800-290-4726 more ways to reach us
Ice loss due to climate change has slightly slowed the Earth’s spin, a new study shows — and it could affect how we measure time. Global warming has slightly slowed Earth's rotation — and it ...
Ice cap climate is the world's coldest climate, and includes the coldest places on Earth. With an average temperature of −55.2 °C (−67.4 °F), Vostok, Antarctica is the coldest place in the world, and has also recorded the lowest temperature, −89.2 °C (−128.6 °F). [ 3 ]