It constantly belches out great clouds of hot gas. This gas is all charged up with electricity, too. This stuff travels at astounding speeds, some of it right toward Earth! The solar wind flows around obstacles, such as planets and moons. However, if a planet has a magnetic field, as Earth does, the charged particles flow around the magnetic field. The solar wind pushes on the magnetic field, flattening it on the side facing the Sun, and pushing it out into a long tail on the opposite side.
See the Picture 3 video. But if you have ever used a compass to find which way is north, you have seen one effect of these lines of force. See Picture 4. The solar wind follows the magnetic lines of force. Notice the glow near the Poles in the Picture 3 video.
They are beautiful curtains of light that move and sway in the night sky. Usually, you can see them only if you live somewhat close to the North or South Pole, far from the equator. See Pictures 5 and 6. Sometimes you can see the auroras far from the North or South Poles. Solar radiation that is not absorbed or reflected by the atmosphere for example by clouds reaches the surface of the Earth.
The Earth absorbs most of the energy reaching its surface, a small fraction is reflected. The Earth radiates energy at wavelengths much longer than the Sun because it is colder. Part of this longwave radiation is absorbed by greenhouse gases which then radiate energy into all directions, including downwards and thereby trapping heat in the atmosphere.
This effect is enhanced by increasing greenhouse gas concentrations in the atmosphere due to emissions by human activities such as burning fossil fuels. But they are not the only forces at work. Water vapour is the most abundant greenhouse gas. It does not stay in the atmosphere for very long but plays a key role in our climate and its variability and change. Ozone in the lower part of the atmosphere acts as a greenhouse gas and is a major pollutant.
Higher up, in the stratosphere, the ozone layer absorbs solar ultra-violet radiation and affects how much of the Sun's heat is radiated back into space. The ozone layer shields us from the harmful effects of excessive UV radiation, which can lead to sunburn, skin cancer and eye damage. The atmosphere also contains small suspended solid and liquid particles.
Aerosols are small dust particles that float in the atmosphere. They result mostly from chemical reactions between gaseous air pollutants, rising sand or sea spray, forest fires, agricultural and industrial activities and vehicle exhausts. Aerosols affect many aspects of human health and the environment, visible in the case of strong smog or haze events. In general, aerosols have a cooling effect on climate, which partially counterbalances the heating effect of greenhouse gases.
Under certain circumstances, however, they may cause additional heating, such as the case of black carbon in soot. The gases and dust particles thrown into the atmosphere during volcanic eruptions have influences on climate and cool the planet by shading incoming solar radiation.
The cooling effect can sometimes last for months to years. Albedo is the ability of a surface to reflect sunlight solar radiation. It is because the heat source for our air actually comes from the Earth.
It turns out that the Sun is so immense large in comparison to the size of the Earth that incoming rays of solar radiation travel basically in parallel lines. But remember our home is not flat it is curved, so incoming solar radiation right in the middle of our planet, near the equator, is absorbed directly.
However incoming solar radiation up towards the poles, at the northern or southern hemisphere comes in at an angle, a much lower angle. As a result less radiation is received. At the equator and near the center of the Earth the story is different — more incoming radiation means more heat energy for the atmosphere.
However higher latitudes with lower incoming Sun angles — little cooler. As you venture north or south of the Equator the incoming solar radiation comes in at increasingly lower angles, and remember lower Sun angles mean less energy received, which in turn means less energy to warm the air.
It turns out that the our planet tilt on its axis is a constant, but its position in relation to the Sun is not. The Earth is on move the it is actually revolving around the Sun. It takes days to make the entire journey.
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