Global Cooling Alert!

[Dauphin]

Originally posted by Azazel
Ramo: Could you refer me to some serious online literature?

Read "Chaos" by James Gleick.

[chequita guevara]

Originally posted by Ramo
The idea behind chaos is that errors in certain highly non-linear systems, can propagate throughout the system disproportionately to the size of the error.

That's only one part of it.

[Ned]

Originally posted by Oerdin
I assume you're talking about the "hot house Earth" senerio. The last one of those (which I can remember hearing about while getting my degree in geology) was around 100 million years ago which isn't very recent even by geologic terms. No, we're talking about current areas covered by the Ross Ice shelf being ice free in the 1750s thus we might consider the melting of the Ross Ice shelf to be a resumption of the status quo rather then an over all warming event.

The theory of global warmiung causing a global ice age has to do with increased evaporation of upper most ocean layers (warmest layers) becoming denser due to the saturation of salt and desolved solids thus leading to a "thermal inversion" meaning they dive under colder water rather then sit on top. That would mean a change in global ocean currents and instead of warm tropical currents heading north south (and warming the higher latitudes) we'd see an east-west trend in currents (meaning tropical heat would stay in the tropics instead of warming places like Europe & Korea/Japan.

Boom, instant accumulation of snow in the north and south leading to advancing ice sheets and a self reinforcing system towards a global ice age.

Oerdin, even accepting that global warming might lead to alterations in ocean currents that may lead to global cooling, the current cooling cannot have anything to do with "global warming." Why do I say this? We do know that the Earth has been dramatically warmer during the current interglacial period without triggering an ice age. Take a look at the attached temperature charts. The lowest high temperature that existed in the last 400,000 years before the plunge into an ice age was 1.5 degrees C above the 1980 norm. We are currently at .2 degrees C above the 1980 temperatures.

Actually the chart shows that we did reach 1.5 degrees C "trigger level" at around 1200 BC. We survived that, I think.

http://www-muller.lbl.gov/pages/climate_plots.pdf

[Berzerker]

We are in what is called an "interstacial", a time when ice sheets retreat and the globe warms. This began roughly 13-14,000 years ago and will (hopefully) continue a few more thousand years. When this period ends, we'll see the ice sheets advance (technically, we're in an ice age) and once again cover much of N Europe and N America unless we can figure out ways to keep the globe warm, it won't be as easy as one might think. And naturally, during an interstacial, the globe warms with small reversals that may have more to do with reduced sunspot activity (which probably caused the mini-ice age of the 1600's) than anything else, so pointing to temperature increases is meaningless. It's claimed cyclical fluctuations in the Earth's orbit and tilt are a major factor in ice advances and retreats, but another theory posits the rise of the Himalayas altered wind currents (jet stream?) causing the "ice age" over the last ~35 million years.

During much of the time of the Dinosaurs, global temperatures were much higher. I suggest anyone concerned with "global warming" track down a temperature graph for the last 100,000 years. You'll see what a joke it is for these "environmentalists" to scream bloody murder about temperature change. They're probably more worried about their operating budgets and donations. The last several thousand years have seen extremely stable temperatures compared to a longer period of time. Temperatures were quite a bit higher during a previous interstacial, so, unless we're going to blame cavemen or the "Atlanteans", man has next to nothing to do with climate.

[Kramerman]

During much of the time of the Dinosaurs, global temperatures were much higher. I suggest anyone concerned with "global warming" track down a temperature graph for the last 100,000 years. You'll see what a joke it is for these "environmentalists" to scream bloody murder about temperature change. They're probably more worried about their operating budgets and donations. The last several thousand years have seen extremely stable temperatures compared to a longer period of time. Temperatures were quite a bit higher during a previous interstacial, so, unless we're going to blame cavemen or the "Atlanteans", man has next to nothing to do with climate.

This is what i say.

I still hafta read the source Ramo gave me tho... its a lot...

[Berzerker]

Oh, btw, just to let you know how intellectually corrupt organisations like the Jet Propulsion Laboratory, i.e., government and it's contractors, can be, one of their spokesmen was on a radio show in LA when I lived out there claiming we needed to support the Magellan Project, a plan to map Venus. Why? So we could prevent the runaway "global warming" that has turned Venus into an oven. I challenged this guy with questions designed to show that the only thing Earth and Venus has in common is diameter. Venus is upside down, virtually no magnetic field, and takes longer to rotate once on it's axis than make an orbit of the sun. Something big hit Venus in the past and it's basicly "dead in the water". But this guy was trying to convince Americans to support wasting alot of money studying Venus to "save" the Earth? Puhlease...

[Berzerker]

Here's a few graphs:

Figure 2 Variations in regional surface temperatures for the last 18,000 years, estimated from a variety of sources. Shown are changes in ° C, from the value for 1900. Compiled by R. S. Bradley and J. A. Eddy based on J. T. Houghton et al., Climate Change: The IPCC Assessment, Cambridge University Press, Cambridge, 1990 and published in EarthQuest, vol 5, no 1, 1991.

[Berzerker]

Figure 6 A schematic reconstruction (solid line) of mean global surface temperature through the last 100 million years, based on analyses of various marine and terrestrial deposits. The dashed-line extension is a prediction of future trends through the coming 400 years, based on the assumption of substantial utilization of the fossil fuel reservoir. The vertical line shows the approximate range of surface temperature in climate model predictions for a doubling of CO2 levels, at about 100 years in the future. Modified from T. J. Crowley, Journal of Climate, vol 3, pp 1282-1292, 1990.

[Berzerker]

Figure 5 Estimate of surface temperature for the last 800,000 years, inferred from measurements of the ratio of 16O to 18O in fossil plankton that settled to the sea floor. The use of oxygen isotope ratios is based on the assumption that changes in global temperature approximately track changes in the global ice volume. Detailed studies for the last glacial maximum provide the temperature scale. Shown are changes in temperature in °C from the modern value. Based on data from J. Imbrie, J. D. Hays, D.G. Martinson, A. McIntyre, A. C. Mix, J. J. Morley, N. G. Pisias, W. L. Prell, and N. J. Shackleton, in A. Berger, J. Imbrie, J. Hays, G. Kukla, and B. Saltzman, eds., Milankovitch and Climate, Dordrecht, Reidel, pp 269-305, 1984.

[Berzerker]

Figure 3 Air temperature near Antarctica for the last 150,000 years. Temperatures given are inferred from hydrogen/deuterium ratios measured in an ice core from the Antarctic Vostok station, with reference to the value for 1900. Compiled by R. S. Bradley and J. A. Eddy based on J. Jouzel et al., Nature vol 329, pp 403-408, 1987 and published in EarthQuest, vol 5, no 1, 1991.

[Ramo]

Berz, just looking at a temperature graph doesn't tell you anything. The current models created by most scientists in the field indicate that human industrial contributions to global warming is significant. I'm willing to trust them, as I'm not an expert in the field.

That's only one part of it

Well, the non-periodocity (if that's what you're referring to) arises out of the non-linearity (and other circumstances). I didn't want to get into it because I'd have to pull out some example differential equations and Mathematica to explain it. Honestly, it's a bit of a mystery to me as far as an intuitive explanation for why this happens goes. Of course, I haven't looked very deeply into the subject.

[Harovan]

Originally posted by Ned
Yeah, let's blame Bush for normal weather. The moron!

While I agree with your last 2 words , it would be wrong indeed to blame Bush for a change of climate. The current effect of global warming (which is an average over the whole surface and may include even local coolings) is caused by the behavior of the whole world (especially the industrialized one) accumulated over the last hundred years or so. So it has been the wrong of all of us. A rethinking and a drastic reduction of CO2 emission is in order, and who refused to do so now (Bush for instance), will be responsible for an even worse climate change in 50 or 100 years. So Bush isn't guilty for the current misery, but he'll be responsible for the future one.

[Lincoln]

Originally posted by Sir Ralph

So Bush isn't guilty for the current misery, but he'll be responsible for the future one.

Oh come on! What a cop out. Bush is responsible for ALL the evil in the world. Try reading some of the threads here on Apolyton and that will prove it!

[Harovan]

I do not necessarily agree with all I read on Apolyton. If I did, I would be stupid. If you do, well...

[Lincoln]

Be of good cheer. I don't either. Thankfully there is a life beyond Apolyton.