The Earth has many negative feedbacks, (emergent phenomenon) like rainclouds thunderstorms even dust devils are examples of phenomenon that are created by heat and act as cooling forces.
In the tropics thunderstorms do not form in the morning, not until there is enough heat and evaporation for them to work, so just by forming 15minutes earlier than normal would be a cooling process.
Stefan Boltzmann law tells us radiation increases to power of 4 with temperature, so that in itself would have a logarithmic effect on earth's temperatures.
So you are correct any exponential climate process would have destroyed earth long before now.
There's at least 2 ways you can have a relatively stable climate:
1. More negative feedbacks than positive ones
2. Limited and/or small positive feedbacks, along with relatively small changes in underlying inputs.
For example, the methane feedback is an inherently limited one. There's only so much methane trapped in the permafrost and the like, so when it's all released, the feedback ends.
And, until recently, the *inputs* were also very slow to change. The long-term changes in solar input were small enough to provide an initial forcing on the order of a degree every 1000 years or so, and feedbacks tend to be proportional to the initial forcing. If you take a system like that and instead make a *large* change in forcing, like doubling a major greenhouse gas in a century or less (which we're... well on track for), then you'll have a much larger change than you've had historically.
And, well, there's stable and there's stable. Read up on Snowball Earth, the various major extinction events, and so on. There have been times when the planet has been a *lot* warmer or colder, it's just that the transitions between states have been much slower in nearly all cases (as far as we can tell).
Before you post on this most permanent of forums, you should probably make sure that you understand the basics, like what language you speak, and the meaning of words.
Relatively stable climate.
Look up both "climate" and "relative"
Global Warming ended in 2012, confirmed by our Satelite reports 11/28/2012. All 4 seasons have returned to normal naturally. This is winter time now. Those are you that are 36+ years old or more may know how it was, so now the rest of you will have to wait and see how our seasons are. Mike
Positive feedback does not always make a system unstable. A positive feedback will only make a system unstable if the effect of the initial feedback is at least as strong as the forcing. Water vapor positive feedback will not make Earth's temperature unstable, because it takes 10C or warming to double the amount of water vapor in the atmosphere, while doubling water vapor will only add about 2C to the temperature.
That is pretty much how science works. We can only account for what is actually known.
Accept the climate models? What I accept is all of the observations being made all across our planet that undeniably shows that our planet is warming. No theory, scientific or otherwise better explains these observations than does the AGWT. Should you have a better theory that unseat the AGWT, then let us see it.
"If you beleive that the earth is 4.5 million years old and that evolution occurs over millions of year, then inherently you would have to believe that the climate of the earth is relatively stable."
Name any climate scientist that would fit these attributions that you have dreamed up.
"Stable systems inherently have more negative feedbacks than positive feedbacks."
Stable systems will have feedback systems that are cancelled out by the other feedback systems. Otherwise you have a state of system imbalance and an unstable climate. Kind of like what we are seeing now.
"The climate models have so many more positive feedbacks that they predict "runaway" global warming and exponential increases in temperature."
The climate models do not incorporate any runaway feedback systems because it is uncertain as to when they would be triggered, what they would be or how strong they would be. Scientists know that they exist, but cannot yet determine when they would be initiated. ... Here is a heads up for you, when you would realize how much energy it would take for the Arctic sea minimum levels to return to the 1979 baseline level then you would see that this is irreversible within a lifetime. Yet, the Arctic sea minimum level has dropped well within my lifetime. What does this do to the albedo effect in the Arctic region?
" If the climate really had all of the positive feedbacks, with so few negative feedbacks, then life would have been destroyed millions of year ago when the CO2 concentration was around 2200ppm." - Source?
Do you lay awake at night dreaming up all of this stuff?
I think you are using an antiquated version of evolutionary theory. Punctuated equilibrium theory allows for a sometimes stable climate, punctuated by catastrophic events like the Permian extinction. Read Stephen J Gould. This is the theory that is most current.
They are political, and willing to believe models that tell them what they want to hear. Models with less warming are discounted. Somehow different physics modeling, with different parameters, end up showing the same amount of warming, because they tune the parameters to produce the amount of warming they want to report.
>>If you beleive that the earth is 4.5 million years old and that evolution occurs over millions of year, then inherently you would have to believe that the climate of the earth is relatively stable. <<
Wrong - as usual. I cannot estimate the number of stupid Denier questions and answers based on the assumption that the earth's climate hundreds of millions and even billions years ago is a reasonable model to use in understanding current global temperature.
Here is just a brief list of things they are too stupid to understand about the earth during the distant past:
The numbers of hours in a day were different;
The number of days in a year were different;
The earth looked and was physically different;
The sun's energy was different;
The moon was closer to earth - enough closer to make a big difference;
The chemistry of the earth's atmosphere was completely different;
It was a completely different world in every way imaginable.
The important concept that covers this changing climate through time is stationarity - and Deniers are as clueless about that as they are of all science.
>>But ANY models that have a more than linear increase in temps with respect to CO2<<
There are no models that have a linear relationship - let alone anything greater than linear.
Do you even know the definition of "linear"?
Here it is: y = ax + b
It has been stated in here numerous times that feedbacks over exceptionally long time periods are, in fact, mainly negative. However, believe it or not, ice ages have come and gone and mass extinctions have occurred. This is due to relatively slow temperatures changes, that being caused by such things as Milankovitch cycles and, on even longer time scales, our galaxies orbit around the galactic center. The presence of mainly negative feedbacks over such long time scales does not mean that abrupt temperature change due to increasing greenhouse gas concentration can not have consequences that are not conducive to our current lifestyles or those of other species. This is why I have a problem with your use of the 'runaway greenhouse effect' as it is generally acknowledge that feedbacks over long time scales are negative. You are attempting to argue against something that is not stated in current scientific literature.
Earth will only have a 'runaway greenhouse' after the warming due to such things as increasing solar radiation gets rid of the cold trap, the tropopause, and allows water vapour to flood higher atmospheric layers and not condense. The presence of water, in all it's forms, is what keeps our climate stable.
Edit: As you increase the amount of CO2 in the atmosphere, if there is no unnatural increase, oceans will begin absorbing more CO2 than they emit. This occurs over very long time periods. Longer yet are Milankovitch cycles and the feedbacks associated with that. I have also seen it stated that our journey around the galactic center will bring various effects as we pass through the spiral arms increasing cloud cover on the planet for various reasons, and so on. There have also been a few instances of snowball Earth. In the past all these effects have been natural and been in balance with one another. What we are doing is overloading the amount of CO2 in the atmosphere thereby forming an imbalance in the system. You are wrong to claim that it would cause a runaway feedback as it has always been a balancing act. And as long as that cold trap exists, regardless if we are still here or not, it will eventually descend back into equilibrium.
JJ-GoodFriendSolidcitizen: Both punctuated equilibrium and phyletic gradualism can exist. It isn't one or the other.
http://necsi.edu/projects/evolution/evol...
I cannot come up with any other reason warmers would so willing accept the climate models.
If you beleive that the earth is 4.5 million years old and that evolution occurs over millions of year, then inherently you would have to believe that the climate of the earth is relatively stable.
Stable systems inherently have more negative feedbacks than positive feedbacks. The climate models have so many more positive feedbacks that they predict "runaway" global warming and exponential increases in temperature. If the climate really had all of the positive feedbacks, with so few negative feedbacks, then life would have been destroyed millions of year ago when the CO2 concentration was around 2200ppm.
The only way I see around this stability issue, is to believe in a young earth. A young earth does not need to have a stable system.
I am convinced that our adding of CO2 to the atmosphere, heats the atmosphere. But ANY models that have a more than linear increase in temps with respect to CO2, is an unstable model. It HAS to be less than linear, to be stable.
My favorite thorn in the bloated AGW theory are D-O events and Bond events. The thermohaline circulation regulates global temps. The worst that AGW can do is trigger an early Bond event.
But, I guess, without runaway AGW, scientists are flipping burgers with that overpriced degree. So you torture the numbers and feed them into a modeling computer. And sell what comes out the other end to politicians.
Yes They think Obama made the World in 2008
to ignore all the weather before .
I would say none are. Creationism is a right-wing Christian delusion, the same side of politics that denialists inhabit
Of course not, nor are all raisins and nuts the only ingredient in fruitcakes.
