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Astronomy - Ch. 9.1: Earth's Atmosphere (54 of 61) Complications with Calculating the G.H. Effect
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- čas přidán 30. 10. 2018
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In this video I will explain some to the various possible contributions of the percentage of the effectiveness contributing factors to the temperature of Earth can be very complicated matter.
Next video in this series can be seen at:
• Astronomy - Ch. 9.1: E...
Oceans and circulation of water is forgotten here yet very important
Oceans and circulation of water has a HUGE impact on the climate, but that is a separate topic than is covered here. This series of videos is covering what happens in the atmosphere.
yes Michel but if you want to calculate the impact of Co2 you should at least put the oceans on the board. This in relation to human Co2 emissions..
Again, time for radiative transfer is ignoring convection - mass transfer is extremely effective at heat transfer.
First of all, very good videos and very well explained!
I was just wondering if there shouldn't be 2 other factors to be concidered here:
1) the periodic orbital changes of earth in relation to the sun (which you also mentioned in a previous video) and
2) the cosmic radiation - even small - that could have an affect on the energy balance but also, as studies suggest, on the creation of clouds (in relation to the activity of the sun)?
As the changes in the climate during the last 10'000 years were quite extreme, wouldn't those 2 points explain most of the effects on the natural climate variation far more than the natural /or man-made changes on CO2 concentrations?
Again, thanks for your videos!!!
The orbital changes, (location of aphelion and perihelion, eccentricity, and tilt) have a HUGE impact on the climate, although those effects have cycles in the thousands and tens of thousands of years. The cosmic radiation tends to be fairly constant and probably does not contribute very much to the changes in the climate. Cloud cover has a definite impact on the temperature and a recent Finish study has confirmed that.
The 'feedback' mechanism of increasing water vapour would lead to a decreased diurnal temperature: a REDUCED day temperature and an increased night temperature, not an overall increase in average temperature. This is measured - no need for a model. This is why desert areas with low water vapour are hotter during the day and colder during the night than tropical areas, and their average temperature is higher. Conclusion - feedback mechanism causes cooing, not heating, because water vapour is better at reducing incoming energy than trapping outgoing energy.
If they deserts of the world are expanding (such as the Sahara), and the air over there deserts contains less H2O, how does that affect a) how much energy is absorbed by CO2, and b) how much energy is retransmitted back into space? Also, how would this differ over a region like the Amazon where there is a lot of uptake of CO2 as well as high H2O concentration in the lower atmosphere?
Yes, the ratios will be different for different areas around the world, for some the % for CO2 will be higher, for others, the % contribution for CO2 will be lower than the numbers shown. The numbers are an approximate average for the different regions of the world.
Michele: Great presentations. Does the absorption of terrestrial IR by water vapor also saturate at a particular concentration and distance like it does for CO2? If so, how would that affect the 'feedback' loop of temp- water vapor?
At certain wavelengths, the absorption is indeed saturated, but not at all wavelengths, and the water vapor content is a lot more volatile, than the other gasses.
I guess that (6) change (2), (5) change (2) , ...
I think it is impossible to create any model.
We have also photosinthesis. When the temperature is going up also photosinthesis should.
Most food around the world is indeed grown where the temperartures are the highest.
What about
- Convection as a heat transfer mechanism
- Solar feedback through solar wind, cosmic rays, clouds (--> Prof. Henryk Svensmark)
- Negative feedback of (6), more water vapor does also mean more clouds (--> Prof. Richard Lindzen)
Recent evidence implies that as the world warms, cloud cover will decrease, so it's a positive feedback, contrary to Lindzen's idea. The cosmic ray idea doesn't hold up because the cosmic ray flux has been steady for 60 years while the world was warming.
Clouds also are the manifestation of a heat pump that transports latent energy to the upper layers of the atmosphere and cools the earth
The formation of clouds is due to the condensation of water vapor in the air. The circulation of the air from lower elevations to higher elevations is one of the primary ways in which the air cools. Another HUGE factor in how the atmospheric temperature and how the climate is affected. A very good point.
@@MichelvanBiezen The following is perfectly correct. WHAT IS E=MC2 is taken directly from F=ma, AS TIME is NECESSARILY possible/potential AND actual ON/IN BALANCE; AS ELECTROMAGNETISM/energy is CLEARLY AND NECESSARILY proven to be gravity (ON/IN BALANCE); AS the rotation of WHAT IS THE MOON matches the revolution. Great.
By Frank Martin DiMeglio
@@MichelvanBiezen What is E=MC2 is taken directly from F=ma, AS the rotation of WHAT IS THE MOON matches the revolution; AS TIME is NECESSARILY possible/potential AND actual ON/IN BALANCE; AS ELECTROMAGNETISM/energy is CLEARLY AND NECESSARILY proven to be gravity (ON/IN BALANCE). WHAT IS E=MC2 is dimensionally consistent ON BALANCE. GREAT. What gravity is, ON BALANCE, is an INTERACTION that cannot be shielded or blocked. Indeed, consider TIME AND time dilation ON BALANCE. What is E=MC2 is taken directly from F=ma. In fact, the stars AND PLANETS are POINTS in the night sky. c squared CLEARLY represents a dimension of SPACE ON BALANCE. Now, ON BALANCE, consider what is THE EYE. Excellent. Think.
By Frank Martin DiMeglio
Ocean currents are a factor as well….
Ocean current have an enormous impact on the Earth's climate.
I recommend to the factor of earths albedo. This is directly influenced by CO2 concentration and can be seen e.g. by the Earth getting greener in the recent past. According to Ralph Ellis (see czcams.com/video/nJL57RDFtzk/video.html ) this would have a real significant effect on the level of dust in the atmosphere settling down on ice causing it to melt. He says that this effect would cause a cooling effect by increasing CO2 levels (as dust levels then decrease) and this outweighs the greenhouse effect of CO2. The industrial warming may well be caused by industrial dust production rather than CO2.
It may be a lot simpler than that. What is always ignored and most likely the biggest factor of all, is the natural variability of the Earth's climate. 18,000 years ago the world was almost 10 degrees C cooler and ocean levels were 400 feet lower than today. Millions of square miles of North America and Eurasia were covered by huge mile thick ice sheets. In a mere 6000 years all those ice sheets melted, the temperature rose almost 10 degrees C and the oceans rose 400 feet, all due to natural causes. Ice core data and sedimentary layer analysis has shown that these types of changes have been occuring for a million years. All without any influence of man.
The water vapor feedback must be nonsense, because it would imply that not only CO2 but water vapor alone could also cause a water vapor feedback.
Water vapor feedback is not nonsense. It is real. But the amount of the feedback has been greatly exaggerated in my opinion.
@@MichelvanBiezen It may be true on a local level and for short time periods, but on a global level it does not make sense, since any temporary warming, e.g. caused by ocean currents would turn the water vapor feedback on and we would see a bistable climate, but thats not what we see.
@@MichelvanBiezen Bistable, because feedback always works both ways: warmer-more water-warmer + colder-less water-colder.
Yes, I agree with your assessment that we would see a "runaway" situation with the climate which we don't see, although there are a number of people who believe that this is currently happening. But their assessment may be less than scientific.
Do you get upset when you see your videos' views
Off course not. Any comment is welcome. (as long as no bad language is used)
It gives me hope that more and more people will look into this from a scientific perspective. It seems on both sides of the argument including the "authorities" people are arguing without a sufficient understanding of the science.