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You can calculate surface temperature using only atmospheric pressure at the surface and solar radiation at the top of the atmosphere. No need for green house gases.


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Gas molecules move very fast and tend to mix more than they tend to settle due to gravity and density. Similar to what happens inside any bottle of liquor. Alcohol is lighter than water but it doesn't float on top, it stays mixed in. The water and the Alcohol mix naturally in part due to their shape and in larger part, due to their charges. Gases aren'...


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Enthalpy of a mixture of gases is determined by this formula: $$h=\Sigma (mf)_ih_i\;[\mathrm {kJ/kg}]$$ $h$ is the enthalpy of unit mass of the mixture, $(mf)_i$ is mass fraction of gas $i$, $(mf)_i=\large{\frac{m_i}m}$ ($m_i$ is the mass of gas $i$ and $m$ is the mass of mixture) $h_i$ is the enthalpy of unit mass of gas $i$ that can be determined by ...


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This actually contains two questions. 1) The sun seems brighter (more dazzling) if there is more scattering in the atmosphere. The sun would actually look very small to us in the sky if there were no atmosphere (it's the same angular size as the moon) and most of the brightness seen in the direction of the sun is from small deflection rayleigh scattering. ...


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As the author of the Gizmondo article you cited explains, [...] scientists believe that emissions spiked due to a combination of warming and drying in the tropics, which can accelerate soil carbon decomposition, and large, drought-fueled fires. Here you can find an equivalent explanation: The atmospheric carbon dioxide concentration is rising year-...


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The article and comment you refer to are not talking about physics. They are talking about the interpretation of CO2 etc measurements according to a belief in the model of "global warming is caused by CO2". After retirement, I spent two years researching the subject and looking into the programming assumptions. I entered interested and not doubting the ...


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It is estimated that aviation is responsible for 12% of transport CO2 emissions worldwide at present (2015 data), with an additional effect due to NO2 and induced O3. Transport itself contributes just over a quarter of all CO2 emissions, with the other main contributions from power (electricity) production, industry, commercial and residential sources, and ...


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Higher frequencies are attenuated (absorbed) more strongly than lower frequencies. Here are a couple of attenuation values from this table of sound-wave attenuation (90% relative humidity): f (kHz) a (dB/km) 1 5.3 2 9 4 20 8 63 The discharge itself will generate a wide spectrum of frequencies, from infrasonic all the way ...


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I am going to steal from an answer to another question. ... a variety of sounds are heard following a lightning strike is not due to dispersion, but rather the multiple branches of the pre-strike, the main strike, and the extended distances covered by the lightning, plus, sometimes, echos. ... In the quote there is a link to a page where they ...


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You got other answers explaining that there are physical reasons in the atmosphere for a sunset to be slightly different from a sunrise. But the problem is that the variations from one day to the other in atmospheric vertical profile (temperature and water vapour) because of meteorological effects are IMHO much greater than the difference caused by the day ...


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I don't know if this is kind of answer you're looking for, but you could measure the temperature difference between the air and the open ground (as dark as possible). Over the course of a day they should diverge because the ground absorbs so much more radiant energy than the air. By sunset they will have equalized some, but by the following sunrise they will ...


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It's not something you can directly see, but various amateur radio propagation modes turn on around dawn and turn off around dusk. Read up on the ionosphere and solar ionization. I imagine this could lead to spectral voids in setting sunlight, but I expect the effect to be too small to see (maybe not too small to measure).


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In real life: A sunset is "redder" than a sunrise which makes people feel more romantic. It's mostly because the atmosphere is warmer in the evening (no pollution here, lemon, the Earth is warmer in the evening because it was naturally warmed up during the day). However, there's also a very small contribution of the Doppler shift, one that you could in ...



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