A BBC documentary with an American voiceover? Do you have something you'd like to discuss, prometheus007?
I do. Seems not very accurate picture of earth's distant future: Please Register or Log in to view the hidden image!Earth's interior heating is now about half of what it was when K40 was the dominate heat source. Also the sun is growing stronger, and slightly larger. Why do they postulate ice covering all and major tectonic movements? I think this may be more accurate picture of earth's future when it is not inhabitable by man: Please Register or Log in to view the hidden image!Won't post. See it as "fig 4" at link of above quote. K40, U238 and especially Th 232 are the dominate heaters in the mantle. I think only heat release there is important for plate tectonics dynamics. U235 was important but with the shortest half life, is now becoming "history." Isotope ..... Heat release [W/kg isotope]...Half-life [years]... kg isotope/kg in mantle ... Heat release [W/kg in mantle] 238U ............ 9.46 × 10−5 .........................4.47 × 109 ...........30.8 × 10−9 .......................2.91 × 10−12 235U ............ 5.69 × 10−4 .........................7.04 × 108 .......... 0.22 × 10−9 .......................1.25 × 10−13 232Th ...........2.64 × 10−5 ........................ 1.40 × 1010 ........ 124 × 10−9 ........................ 3.27 × 10−12 * 40K .............. 2.92 × 10−5 .........................1.25 × 109 ........... 36.9 × 10−9 ...................... 1.08 × 10−12 * With highest mantle concentration, longest half life, and yet greatest mantle heating, Th232, increasingly dominates plate tectonics. There seems to be a unusually high concentration of thorium in the US's NW. Perhaps under Yelowstone National Park. With only a 7x10^8 half life and already greatly reduced concentration U235 is telling man, he better find out how to make controlled fusion work. After 6+ decades, of trying, he can't do that yet Graph and table data from: http://en.wikipedia.org/wiki/Geothermal_gradient
That was a very inconsistent video. The music was more menacing than what was being said. A few added scenes (reenactments) were extreme but when listening to most of the scientists there was nothing to justify the statements about man perhaps not surviving or the pictures of snow and ice covering everything. In one sentence they did away with the Atlantic ocean and all its water..."due to the subduction zone". The plates will come together but the water isn't going to disappear. Sure, in 100,000,000 years the climate will be changed. They go from suggesting that man may be wiped out to saying that NYC may no longer exist. So what, of course coastal cities will change and when talking about 100,000,000 years that's the least of the changes that would occur. The basic science is sound but the made up conclusions aren't necessarily.
Correct me if I'm wrong, but I thought that any significant changes in the Sun's size or temperature, won't occur for more than a billion years....closer to two billion or more from memory.
The intensity increase is continuous and I think accelerating, but only remember that the sun is now brighter by about 30% than when it was first became a relatively stable radiator. I vaguely recall its energy out put is now increasing about 10% per billion years. (0.01% per million years) I'm not good at searching -Perhaps you will check my memory?
Eh? What subduction zone are they talking about? There isn't one in the Atlantic, so far as I know. So there is no current mechanism for the Atlantic to close, is there? Or are they postulating the appearance of a new subduction zone somewhere?
Ah, thanks for this, I didn't know about it. But, from what I read here: http://www.earthmagazine.org/article/new-subduction-zone-may-close-atlantic-ocean …...there is no subduction zone as yet, and it is too early to tell whether the thrust faults they have found will develop into a subduction zone. If it does, they expect that process to take 10 million years and the closure of the Atlantic a further 200 million years after that.
