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You're talking about a timespan of 250 million years in which there were a series of ice ages and warming periods due to huge swings in CO2. These CO2 swings were caused by cycling between extreme periods of weathering (Carbonate–silicate cycle - Wikipedia) and volcanism.Originally Posted by Mark Rippetoe
Snowball Earth – Historical Geology
Water vapor is responsible for most of the greenhouse effect, but does not cause climate change. This is due to the fact that the atmosphere is physically limited on how much water vapor it can hold (saturation vapor pressure). However, since saturation vapor pressure is temperature dependent, water vapor amplifies the warming effect caused by other greenhouse gasses.
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you are making the critical error of reading the text and not looking at their data. Their data does not conclude this.
No, it shows they correlate. When the ocean warms it releases CO2. This point is not disputed. The rise in temperature almost always (outside the industrial era) precedes the rise in CO2.
TMPHBITEU
How do you know that CO2 was the primary factor in the warming periods? Because it fits your belief system?
And the other "greenhouse" gasses obviously do not affect the climate, or there would have been no global glaciation with CO2 at 6000 ppm. Therefore, climate change is dependent on extra-atmospheric phenomena. Stop watching NBC News and begin to think, please.Water vapor is responsible for most of the greenhouse effect, but does not cause climate change. This is due to the fact that the atmosphere is physically limited on how much water vapor it can hold (saturation vapor pressure). However, since saturation vapor pressure is temperature dependent, water vapor amplifies the warming effect caused by other greenhouse gasses.
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Congratulations, this is the most idiotic thing I have read from someone defending AGW, and I have been exposed to some stupid shit.
In one sentence you managed to state a fact, and then immediately dismiss it. You then follow up with a rudimentary explanation of psychrometrics throwing out some sciencey sounding bullshit about saturation pressure limits. We know what humidity is - the grains of water the air can carry that varies with temperature and pressure, and it varies greatly over the globe at any given time. You going to try and tell us 'the science' can say that 250m years ago we knew what the humidity was with enough precision to tease a co2 signal out of that data AND attribute the GMST changes to this (generally much higher) co2 level? I'm going to not believe that without some very convincing evidence, and everything I've seen from the AGW pushers is junk.
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Yes it does. The r-values from the statistical analysis are listed right above Figure 4.
Correlation Coefficient | Introduction to Statistics | JMP
The Ocean is a CO2 sink and releases less CO2 than it has absorbed. Phytoplankton absorb CO2 using photosynthesis and then some of that Carbon makes its way to the Ocean floor.No, it shows they correlate. When the ocean warms it releases CO2. This point is not disputed. The rise in temperature almost always (outside the industrial era) precedes the rise in CO2.
Please provide a reference that concludes a rise in global temperatures almost always precedes the rise in CO2.
No, it's because that's what the data shows. Determining dependency on a multi-variable system is not some crazy difficult thing to do (outside of colleting the data in this case). But study after study has shown that atmospheric CO2 is the main driver for global climate variations. This is not NBC news putting these studies together.
There are other greenhouse gasses that could affect climate, but I don't think it was cow farts that got us out of the last ice age. There is just way more CO2 than methane. Adding tens of billions of tons of CO2 to the atmosphere every year can make a big difference over time.
Climate change is not solely dependent on extra-atmospheric phenomena.
3.1 Changes in Solar Output and in the Earth’s Atmosphere – Environmental Geology
Climate change and the greenhouse effect are two different things. If there is a change in the global greenhouse effect then that can cause climate change. Water vapor is the primary greenhouse contributor in our atmosphere. Without water vapor in our atmosphere, our planet would basically be frozen. However, water vapor does not drive climate change because it's concentration in our atmosphere is physically limited. You're welcome to read about this "sciency sounding bullshit" here:
Vapour pressure of water - Wikipedia
The only way water vapor could contribute to long-term climate change is if there were changes to the atmospheric pressure or temperature. That is why water vapor is not a driver for climate change but can amplify the effects. For example, a rise in atmospheric CO2 => air temperatures increase => increased water vapor in the air => even higher air temperatures.
Why do we blame climate change on carbon dioxide, when water vapor is a much more common greenhouse gas? | MIT Climate Portal
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Can you elaborate on that please? explain like I'm 7.
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https://geoweb.princeton.edu/people/..._1999_copy.pdf
They use the typical misleading trick of putting zero, ie the present, at the far left of the graph. CO2 concentration responds to temperature, not vice versa.
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Ok, temperature is simply an indication of the energy deposited and retained by the sun. We know the suns output changes, we know the orbital path of earth changes, precession changes the amount of energy absorbed. We know concentration of ions that seed clouds (ie visible water vapor) from both the sun and the cosmos changes, which will greatly affect the amount of energy the surface of earth sees (ie albedo taken as a whole).
We KNOW this energy flux varies, causes temperatures to vary, and therefore water vapor's (recall even you said its the strongest greenhouse gas) ability to warm the planet. Why again are we a) so confident that we can tease a co2 effect signal out from the historical data on all these proxy measurements over water vapor, and b) make the further leap to conclude that this weak greenhouse gas is somehow the 'control knob' of earths temperature?
Bonus question: if we are wrong it is still historically cold even within human evolutionary history; this is not disputable. Explain to me like I'm 7 why it would be bad if it were a couple degrees warmer over the next 100 years.
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The Sun hits the Earth with an incredible amount of energy [1], about equivalent to the power of 170 billion nuclear reactors [2]. Some of that solar radiation is absorbed by the Earth's surface, which warms it. Some of it is lost to space and some of it is trapped as heat in the atmosphere by greenhouse gases. Greenhouse gas include water vapor, carbon dioxide (CO2), methane, nitrous oxide, fluorinated gases and others. All of this has been relatively balanced for a very long time. Without any greenhouses gases in our atmosphere, our Earth's average temperature would be about -4F [3]. Currently, water vapor is responsible for about 67% of the total greenhouse effect in our atmosphere, CO2 is about 24%, and all others are responsible for about 9% [4]. The total greenhouse effect of each greenhouse gas is dependent on how strong the greenhouse gas is and the amount that is in the atmosphere.
The Earth's average temperature has steadily been increasing the last ~100 years [5]. The vast majority of scientists believes this increase in temperature is due to the rise of CO2 from human emissions and not because of solar variation [6]. Why do they believe CO2 is the cause of this climate change instead of water vapor, if water vapor has a stronger impact on our atmosphere's greenhouse effect? Because the atmosphere is physically limited to how much water vapor it can hold and the amount of time water vapor is in our atmosphere is quite short (it is continually evaporating and condensing). The amount of water vapor in our atmosphere stays relatively constant and there's almost nothing we can do to change it. For example, a cooling tower from a nuclear reactor can pump millions of pounds of steam into the atmosphere, but it's going to have a negligible impact on global climate because the water vapor will condense and be out of the atmosphere in a few days. On the other hand, we continually pump tens of billions of tons of CO2 into our atmosphere ever year and have disrupted the natural balance (since well before human civilization) between natural CO2 emissions and removal; therefore, continually adding CO2 concentrations in our atmosphere and increasing its greenhouse effect [7].
References and notes:
[1] Energy On a Sphere - Science On a Sphere
[2] 173,000 TW divided by 1000 MWe (typical electricity output from a US light-water reactor) is equal to 170 billion.
[3] The greenhouse effect - British Geological Survey.
[4] https://web.archive.org/web/20111022...idt_etal_1.pdf
[5] Global Temperature | Vital Signs – Climate Change: Vital Signs of the Planet
[6] Is the Sun causing global warming? - NASA Science
[7] https://www.climate.gov/news-feature...carbon-dioxide
TMPHBITEU
From your reference #4: https://web.archive.org/web/20111022...idt_etal_1.pdf
Attribution of the present‐day total greenhouse effect
Gavin A. Schmidt,1 Reto A. Ruedy,1 Ron L. Miller,1 and Andy A. Lacis1
Received 30 March 2010; revised 27 July 2010; accepted 3 August 2010; published 16 October 2010.
[1] The relative contributions of atmospheric long‐wave absorbers to the present‐day
global greenhouse effect are among the most misquoted statistics in public discussions
of climate change. Much of the interest in these values is however due to an implicit
assumption that these contributions are directly relevant for the question of climate
sensitivity. Motivated by the need for a clear reference for this issue, we review the
existing literature and use the Goddard Institute for Space Studies ModelE radiation
module to provide an overview of the role of each absorber at the present‐day and under
doubled CO2. With a straightforward scheme for allocating overlaps, we find that water
vapor is the dominant contributor (∼50% of the effect), followed by clouds (∼25%)
and then CO2 with ∼20%. All other absorbers play only minor roles. In a doubled CO2
scenario, this allocation is essentially unchanged, even though the magnitude of the total
greenhouse effect is significantly larger than the initial radiative forcing, underscoring
the importance of feedbacks from water vapor and clouds to climate sensitivity.
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