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Atmospheric electricity is always present, and during fine weather away from thunderstorms, the air above the surface of Earth is positively charged, while the Earth's surface charge is negative. This can be understood in terms of a difference of potential between a point of the Earth's surface, and a point somewhere in the air above it.
The radio window is the region of the radio spectrum that penetrate the Earth's atmosphere. Typically, the lower limit of the radio window's range has a value of about 10 MHz (λ ≈ 30 m); the best upper limit achievable from optimal terrestrial observation sites is equal to approximately 1 THz (λ ≈ 0.3 mm). [1] [2]
This radiation is in the infrared portion of the spectrum, but is distinct from the shortwave (SW) near-infrared radiation found in sunlight. [1]: 2251 Outgoing longwave radiation (OLR) is the longwave radiation emitted to space from the top of Earth's atmosphere. [1]: 2241 It may also be referred to as emitted terrestrial radiation. Outgoing ...
The Earth–ionosphere waveguide [1] is the phenomenon in which certain radio waves can propagate in the space between the ground and the boundary of the ionosphere. Because the ionosphere contains charged particles, it can behave as a conductor. The earth operates as a ground plane, and the resulting cavity behaves as a large waveguide.
Critical Frequency changes with time of day, atmospheric conditions and angle of fire of the radio waves by antenna. The existence of the critical frequency is the result of electron limitation, i.e., the inadequacy of the existing number of free electrons to support reflection at higher frequencies.
When the air reaches the polar areas, it has cooled by radiation to space and is considerably denser than the underlying air. It descends, creating a cold, dry high-pressure area. At the polar surface level, the mass of air is driven away from the pole toward the 60th parallel, replacing the air that rose there, and the polar circulation cell ...
The covariant formulation (on spacetime rather than space and time separately) makes the compatibility of Maxwell's equations with special relativity manifest. Maxwell's equations in curved spacetime , commonly used in high-energy and gravitational physics , are compatible with general relativity .
Meanders of the Northern Hemisphere's jet stream developing around the northern polar vortex (a, b) and finally detaching a "drop" of cold air (c). Orange: warmer masses of air; pink: jet stream; blue: colder masses of air. Rossby waves, also known as planetary waves, are a type of inertial wave naturally occurring in rotating fluids. [1]