The only thing that has been proved is that our planet's climate changes. Everything else is conjecture.
Does anyone know what causes ice ages, e.g. planetary cooling? Lots of people have theories, but no one really knows. The bottom line- we don't know why the Earth is colder sometimes and warmer others, and we can't be sure which direction the normal cycle is going, although if we are basing our theories on conjecture, the theory would be that we are in a natural warming cycle. But that is irrelevant. Whatever the direction of the trend, we can't do anything about it. The planet is going to do what it is going to do. http://en.wikipedia.org/wiki/Ice_age Causes of ice ages The causes of ice ages remain controversial for both the large-scale ice age periods and the smaller ebb and flow of glacialinterglacial periods within an ice age. The consensus is that several factors are important: atmospheric composition <http://en.wikipedia.org/wiki/Earth%27s_atmosphere> (the concentrations of carbon dioxide<http://en.wikipedia.org/wiki/Carbon_dioxide>, methane <http://en.wikipedia.org/wiki/Methane>, sulfur dioxide<http://en.wikipedia.org/wiki/Sulfur_dioxide> ,[*citation needed <http://en.wikipedia.org/wiki/Wikipedia:Citation_needed>* ] and various other gases and particulates<http://en.wikipedia.org/wiki/Particulate>in the atmosphere); changes in the Earth's orbit around the Sun <http://en.wikipedia.org/wiki/Sun> known as Milankovitch cycles<http://en.wikipedia.org/wiki/Milankovitch_cycles>(and possibly the Sun's orbit around the galaxy<http://en.wikipedia.org/wiki/Milky_Way#Sun.27s_location>); the motion of tectonic plates <http://en.wikipedia.org/wiki/Plate_tectonics>resulting in changes in the relative location and amount of continental and oceanic crust on the Earth's surface, which could affect wind<http://en.wikipedia.org/wiki/Wind>and ocean <http://en.wikipedia.org/wiki/Ocean_currents> currents<http://en.wikipedia.org/wiki/Atmospheric_circulation>; variations in solar output <http://en.wikipedia.org/wiki/Solar_activity>; the orbital dynamics of the Earth-Moon system; and the impact of relatively large meteorites <http://en.wikipedia.org/wiki/Meteorite>, and eruptions of supervolcanoes <http://en.wikipedia.org/wiki/Supervolcano>. Some of these factors are causally related to each other. For example, changes in Earth's atmospheric composition (especially the concentrations of greenhouse gases) may alter the climate, while climate change itself can change the atmospheric composition (for example by changing the rate at which weathering <http://en.wikipedia.org/wiki/Weathering> removes CO2). William Ruddiman <http://en.wikipedia.org/wiki/William_Ruddiman>, Maureen Raymo, and others propose that the Tibetan and Colorado Plateaus are immense CO2 "scrubbers" with a capacity to remove enough CO2 from the global atmosphere to be a significant causal factor of the 40 million year Cenozoic Cooling trend. They further claim that approximately half of their uplift (and CO2 "scrubbing" capacity) occurred in the past 10 million years.[9]<http://en.wikipedia.org/wiki/Ice_age#cite_note-8> [10] <http://en.wikipedia.org/wiki/Ice_age#cite_note-9> On Fri, Apr 4, 2008 at 11:51 AM, Jim wrote: > > Global Warming really isn't at issue here... the fact of it is too obvious > to be ignored by any reasonable person. The very reasons that we're > arguing > so heatedly about human causes is that the fact of global warming has been > established: we're into the "why" phase of investigation. > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Adobe® ColdFusion® 8 software 8 is the most important and dramatic release to date Get the Free Trial http://ad.doubleclick.net/clk;192386516;25150098;k Archive: http://www.houseoffusion.com/groups/CF-Community/message.cfm/messageid:258048 Subscription: http://www.houseoffusion.com/groups/CF-Community/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=11502.10531.5
