seismic dunedain

Fair enough

I couldn't agree more. I am not sure why anyone thinks I disagree. I merely think that the idea we shouldn't look beyond the last 100,000 years to be a misguided sentiment. Climate scientists can and do look much further back and I was just explaining why. I see, because I posed the question "what if Global warming isn't caused by us and it's just a natural cycle?" it sounds as if I don't believe global warming is anthropogenic. But I just wanted to draw attention to the fact that this question is one that needed to be addressed by climate scientists. And one of the ways they did address that question is by looking back much farther than the last 100,000 years. Alright, I think we might all be on the same page now.

First of all, you are correct that the Earth is not exactly the same as it was in the past but it is SIMILAR enough that we can draw scientific value from studying it. We shouldn't just ignore an entire body of evidence because it's not a perfect body of evidence. In fact, all of sedimentary geology is based on whats called the principle of Uniformitarianism which basically says "The key to the prast is the present". So basically geologists make the assumption that the Earth today is very similiar to the ancient Earth. How else could a geologist look at 500 million year old sandstone and draw conclusions about the environment that sandstone was deposited in? So it isn't a bad assumption at all, it's the assumption that sedimentary geology is based on. Who said "It's natural" is some magic bullet. I certainly didn't. What I said that it's a valuable question to ask if our current global warming is part of natural cycle. And I wasn't telling what climate scientist SHOULD do, I'm telling you that they DO spend a lot of effort studying ancient paleo-climatology to help answer that question. You seem to have assumed that I deny global warming, which of course is not what I did if you read my post.

good question. But we should consider much longer than just the last 100,000 years, that's a blink of an eye in geologic time. The reason we should be considering long time scales is so that we can understand how much of the current global change is anthropogenic. For instance, how do we answer this question "what if Global warming isn't caused by us and it's just a natural cycle?" Well we would need to know how the Earth's climate has changed throughout its history to determine how much of the current global change is anthropogenic and how much is a natural paleo-climactic cycle. By the way, this whole article is garbage. First of all, if volcanic eruptions cause cooling then it is probably because of the ash and soot that eruptions eject into the atmosphere and nothing to do with the greenhouse gases. Second, just so we're all clear, Human sources of Co2 are an order of magnitude greater than volcanic activity. And what the hell was with all the political crap. This is the problem with so many people with an opinion on global warming, they don't know or care one iota about the actual science, they just have some political-economic agenda they want to advance and they'll spread all kinds of garbage. That's why the public is so confused. You have left-wing fear-mongers telling us that global warming is leading us to a Doomsday apocalypse and right-wing greedy morons telling us that it's all a myth. The truth is that global warming IS real and it WILL be a challenge for the future, but it won't result in any sort of apocalyptic disaster. '

To say we developed high intelligence because of appendages and sense organs to me sounds glib. Just because someone has a wrench does not mean he can build a car. Also, the other primates already had these appendages and sense organs and so this does not explain the leap between the Homonid species from our predecessors. Am I unclear about something? I guess I find a lot of the explanations here unsatisfying.

Hi Juryoku, When someone likes geology and physics I am very quick to suggest geophysics(not least because I am a geophysicist). It combines physics and geology to work on some really interesting problems. For instance, geophysics is taking a leading role in global warming mitigation with something called Carbon capture and storage(CCS). The idea with CCS is to capture CO2 produced by industry and store it deep underground in porous rock. The role of geophysics in this is to find the places where this can be done, and then monitor the CO2 to make sure it isn't leaking. Other geophysics topics include earthquakes and plate tectonics and oil exploration. Geophysics is very applied and there are lots of jobs, especially in oil exploration(which is what I do) best of luck to you no matter what you choose.

I don't really know what the topic is except maybe panic, but I can reassure everyone so they can sleep tonight that this planet will survive us and it will be alive and well long after we're gone.

an infinite layer of zeros would equal zero. Everything did not come from one big nothing. We don't know what caused our universe to come into existence. call it God(actually, there is something called the fine tuning problem which suggests that our universe might have had to have been created by God and this is the subject of Stephen Hawkings book The Grand Design) or if you don't like God, you can imagine that maybe our universe is like a bubble and it formed by popping off of a much larger universe(the collection of all these conjectured universes is often referred to as the multi-verse) But whatever explanation you like, the fact is that we just don't know what caused the big bang, but there had to have been energy and fundamental forces at least to have caused it.