Was that caused by a volcano eruption or giant undersea earthquake? I completely missed it.
See I thought that CFCs, that you credit the increased warming of the earth to, were anthropogenic compunds. But then you just finished telling me that anthropogenic global warming had fallen flat on its face.
The phrase 'trap more heat' means to hold a greater quantity of heat energy at any given moment.
The energy will still be able to escape, so it is not 'never let go', but there is more of it within the containment area of interest.
Take a house, as an example. If I put the heater on, the heat energy in the house will go up. Heat energy will still leave through the walls, windows and roof etc. If I open a window, heat energy will escape more quickly. If I install insulation, more heat will be trapped. Heat will still escape the trap, but at a slower rate than before. Since the heater is still generating the same amount of heat energy, the overall heat energy in the house will go up.
You are talking about restricting convection of heat with your example.
Except with the window, it's actually mostly conduction.
With co2, it absorbs heat energy and then releases it.
And with more carbon dioxide there is more heat energy absorbed.
What evidence do you have to suggest the temporary entrapment of heat by co2 slows the release of heat into space?
That wasn't the claim I made. I simply stated that 'trapping heat' does not mean 'trapped forever'. I'm fairly sure the evidence you are asking for here has already been presented, and you have already rejected it. Is there much point in presenting it again? Here is something NASA wrote for all the good that it will do. The phenomena is called energy imbalance. Eventually all the heat the earth takes in, will radiate out, but it can, for periods of time, take in more heat that it radiates back out:
quote:Energy imbalance arises because of changes of the climate forcings acting on the planet in combination with the planet's thermal inertia. For example, if the Sun becomes brighter, that is a positive forcing that will cause warming. If Earth were like Mercury, a body composed of low conductivity material and without oceans, its surface temperature would rise quickly to a level at which the planet was again radiating as much heat energy to space as the absorbed solar energy.
Earth's temperature does not adjust as fast as Mercury's due to the ocean's thermal inertia, which is substantial because the ocean is mixed to considerable depths by winds and convection. Thus it requires centuries for Earth's surface temperature to respond fully to a climate forcing.
I'm saying the word trapped is misleading because it suggests co2 holds onto the heat long enough to cause an imbalance and increase the temperature of the earth.
Well that's not what you said, you said
quote: Trap means to never let it go. You cannot be serious that when co2 absorbs radiation, it keeps it forever?
But that's not the case. Heat is transferred to nitrogen and oxygen via conduction from co2 molecules and from the surface of the earth itself. Heat is truly trapped by these molecules for a very long time before convection raises the warmer air to higher elevations where the air becomes colder and drops again.
There are other heat transfers taking place too. You mention 'from the surface', but also 'to the surface', for instance - including notably the ocean and to a degree, the ice. You also neglect the fact that N2 and O2 don't absorb infrared photons, while CO2 and CH4 does.
But they certainly absorb through conduction and there are vastly more of them than co2
Yes they do. But where are they absorbing it from? A number of sources, but CO2 is one of them - as are other greenhouse gasses. Where is CO2 getting it from? From absorbing it from the IR radiating from the earth's surface.
This will result in higher atmospheric temperatures as that o2 will also conduct heat to things such as the ground and people etc.
Without the greenhouse gasses, the IR will not be absorbed by them and less heat will be absorbed by the O2 and N2, and the O2 and N2 won't be able to conduct that heat back into people...or oceans.
therefore it's disingenuous to say co2 traps heat when trying to make a case for AGW because n2 and o2 hold onto heat for a much longer time.
No it's reasonable to say adding more CO2 to the atmosphere will trap more heat, as that is precisely what happens. The fact this heat gets transferred to other atmospheric molecules doesn't alter the fact that it was CO2 that captured it in the first place.
As for heat transfer to the ocean and ice, that also occurs through conduction.
Exactly. So more heat being stored in O2 and N2 and other atmospheric gasses increases the conduction to the ocean and ice from the atmosphere.
But since the ocean holds vastly more heat than the atmosphere, the net transfer of heat is from ocean to ice and the atmosphere.
Do you have evidence that the oceans are cooling now? This is strange because 10 weeks ago (almost to the minute, see Message 311) you said:
quote: In short, the co2 concentration is rising because of warming oceans.
If the oceans are warming, yet are giving up more energy to the ice and atmosphere, where is all the extra energy coming from? '3% extra ultraviolet B radiation?' caused by CFCs - Can you show your working?
And if the net conduction is away from the oceans, might it be a problem if this net conduction amount decreases?
All the gases are heated up by either thermalization from co2 or from contact with the warm ground. How does that make your case for co2 being the cause of a warmer atmosphere than would be without it?
I'm willing to concede that if our atmosphere consisted solely of the carbon molecules currently present and none of the other gasses, it'd be frickin cold here.
But we are talking about the atmosphere we do have. In that atmosphere, adding carbon dioxide captures more of the infrared radiation emanating from the earth's surface. These carbon molecules then transfer that heat to other things, such as the rest of the atmosphere, the ocean back to the surface etc. More heat, leads to higher temperatures.
Conversely, less carbon molecules capture less radiation, meaning more of this heat escapes without heating the atmosphere. Less heat being trapped in the atmosphere leads to lower temperatures.
Another point is that climate change is a controversial topic and so sources for both sides of an issue can be equally credible.
They can be, but that doesn't mean they are. It's actually not a controversial topic - the only real controversy is how we respond to it.
The Roswell incident is a controversial topic, by some measure. The story that a modified weather balloon holding a microphone as an experimental nuclear bomb detonation detector was covered up by the military as a national security secret is more credible than the military covering up interstellar aliens.
Very little is accepted in climate science publications that does ot support the notion that co2 is the cause of global warming
Two possibilities: 1) Systemic bias 2) Contrary views are not supported
How much is accepted in medical journals that heart attacks are not deleterious to health?
No pro AGW article I have ever seen even attempts to address any of the issues Dan brings up.
Solar activity and water vapour are very much discussed in climate change science.
quote:The study identifies no statistically significant correlations between cloud anomalies and TSI/GCR variations, and concludes that solar-related variability is not a primary driver of monthly to annual MODIS cloud variability. The authors observe a net increase in cloud detected by MODIS over the past decade of; 0.58%, arising from a combination of a reduction in high-to midlevel cloud (20.31%) and an increase in low-level cloud (0.89%); these long-term changes may be largely attributed to ENSO-induced cloud variability.
quote: The best estimates of the solar influence on the global mean air surface temperature show relatively small effects, compared with the response to anthropogenic changes (and broadly in line with their respective radiative forcings). However, the situation is more interesting when one looks at regional and season variations around the global means. In particular, recent research indicates that winters in Eurasia may have some dependence on the Sun, with more cold winters occurring when the solar activity is low. Advances in modelling “top-down” mechanisms, whereby stratospheric changes influence the underlying troposphere, offer promising explanations of the observed phenomena. In contrast, the suggested modulation of low-altitude clouds by galactic cosmic rays provides an increasingly inadequate explanation of observations.
quote: The conditions necessary for this picture to be wholly or partially wrong are then introduced. Evidence is presented from which the contributions of either cosmic rays or solar activity to this warming is deduced. The contribution is shown to be less than 10% of the warming seen in the twentieth century.
quote: Our long-term analysis of MISR data finds no statistically significant correlations between cosmic rays and global albedo or globally averaged cloud height, and no evidence for any regional or lagged correlations. Moreover, epoch superposition analysis of Forbush decreases reveals no detectable albedo response to cosmic ray decreases, thereby placing an upper limit on the possible influence of cosmic ray variations on global albedo of 0.0029 per 5% decrease. The implications for recent global warming are discussed.
quote:Thus, to explain observed global warming via CR modulation of albedos, it is necessary to postulate that a 5% decrease in the CR flux decreases global albedo by around half a percent. Fortuitously, the secular decrease in the CR flux since 1891 is equal to the average Fd magnitude in our composite analysis. Thus, if CR flux decreases were responsible for recent warming, then an albedo signal should be visible in our Fd analysis since the 95% confidence interval extends to only 0.0029. Instead, we observe that there is no global albedo response to a 5% decrease in CRs greater than 0.0029 and no hint of any weaker signals imbedded in the noise either.
A short term change in cosmic ray flux is unlikely to show up in total global albedo. The effect of cosmic rays is most likely to be long term and it's most intense effect would be in the intertropical convergence zone. An enormous amount of heat is lost to space in this zone through thunderstorms and hurricanes and cyclones. The sun also shines more directly in this zone than the other latitudes.
Words. I'll repeat the science:
quote:The contribution is shown to be less than 10% of the warming seen in the twentieth century.
I don't know what counts as 'long term', but the study you quoted goes back to the turn of the twentieth century.
quote:The analysis above suggests that modulation of albedo is not responsible for the majority of global warming since 1900.
quote:One caveat on these conclusions is that the upper bound of 0.0029 per 5% CR decrease was derived exclusively in the context of short timescale Fds. It is conceivable that CRs influence climate via some unknown mechanism that only acts on longer timescales, and thus wouldn’t be apparent during brief Fd episodes. However the majority of CR mechanisms proposed in the literature would be expected to manifest themselves on short timescales since the effects of CRs on atmospheric ionization are immediate, and cloud formation processes operate on the order of hours to days.
Although both short and long term analysis did not uncover any evidence for spatially localized CR cloud correlations, local effects cannot be dismissed because the grid size of block-averaged MISR data is large and the sampling errors in regional correlations are too large to tightly constrain the magnitude of local effects.
I still contend that your claim that
No pro AGW article I have ever seen even attempts to address any of the issues Dan brings up.