Todays World: Ice House or Hot House? (great info on debunking global warming)

"The limits of climate models prevent exact predictions as it is impossible to include in the model all possible parameters and feedbacks."

THIS is the only true phrase in your comment. Your models don't begin to take into account all the drivers and sinks of the planetary heat budget. The sun's magnetic field has doubled. Where is THAT accounted for in your models?? It MUST have an effect--basic physics says that.

Two questions before I reply so I know if we have some common ground here.

Do you regard the chart in post 15 on this thread as a reasonably accurate representation of temperature and CO2 levels?

Where do you see us at this moment on the chart in terms of temperature and CO2?

How do you know we are in 'a very stable interglacial period?'

Sorry for my tardy reply, I was unexpectedly out-of-touch for a few days.

Do you regard the chart in post 15 on this thread as a reasonably accurate representation of temperature and CO2 levels?

Over geological history, yes. But it doesn't resolve the Holocene or the Pleistocene glacial/interglacial period at all.

Where do you see us at this moment on the chart in terms of temperature and CO2?

Beyond the end of it.

How do you know we are in 'a very stable interglacial period?'

Because I do. And the plots below illustrate why. The first plot shows temperatures (blue) and CO2 concentrations (red) from Antarctic ice cores from 420,000 years ago to present. The second plot is a close-up of the last 18,000 years only (same data as the first plot). You can see in the first plot how "jumpy" temperatures were in previous interglacials (the warm periods) -- and the glacial periods weren't much more stable. The second plot shows clearly how stable the past 11,000 years have been, and this is the period since the most recent retreat of the continental glaciers. In truth, this is an abnormally stable interglacial period.

Are the degrees and ppm on your two charts equivalent to the same figures on the chart in the thread? Or are they measuring different things--eg one is measuring average temperature in antarctica and another on the equator or some such difference?

Degrees and ppm are the "same thing" on both charts, but there is a definite caveat. What I would call "deep time" paleotemperatures are usually based on a compilation of oxygen-18 measurements from ocean sediment cores. The O18/O16 ratio is a paleothermometer, and the ratio is derived from oxygen atoms in biogenic calcium carbonate in sediments. (Biogenic means produced by living things, so these are usually carbonate plankton). Because the plankton grab O (in carbonate ion) from the oceans to make their shells, they capture the existing 018/016 ratio at the time. This is a paloeothermometer because the colder the seawater gets, the more O18 it will have.

The ice cores are from Antarctica, and paleotemperatures are determined the same way, but this time the O18/O16 is from the actual ice (H2O) formed in the atmosphere. This is more direct, but it's also more regionally specific for Antarctica. The cores also have much better time resolution, but over millions of years the ocean sediment cores are sufficient for geological climate research.

Before worrying too much about the regional specificity of Antarctic temperatures, note that the ice cores reliably record global climate changes, some very specific. One very interesting one is the "8200 year spike", a quick up-down recently attributed to the released of flood water from the remnant glacial lakes in Canada into the North Atlantic. You can see that on the second chart I posted. Even though the main effects were in the North Atlantic and Northern Hemisphere, the Antarctic cores caught the resulting short temperature aberration.

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