Video & Multimedia
Related: About this forumResponse to Courtesy Flush (Original post)
elocs This message was self-deleted by its author.
I'm not sure what kind of life would survive runaway warming.
Response to truebluegreen (Reply #3)
elocs This message was self-deleted by its author.
truebluegreen
(9,033 posts)Earth could become like Venus, "Average temperature there is a hellish 735 Kelvin, or 462 degrees Celsius hot enough to melt lead.
Venus remains that same temperature no matter where you go on the planet. At the North Pole? 735 Kelvin. At night? 735 Kelvin. Daytime at the equator? 734 Kelvin."
Read more: http://www.universetoday.com/102973/what-is-the-hottest-planet-in-the-solar-system/#ixzz2oJw4fYCU
truebluegreen
(9,033 posts)except I'm too much of a Luddite to know how to insert the video. I'm glad you got it done.
It IS mind-blowing.
Courtesy Flush
(4,558 posts)It's so easy that it throws people off. All you need is the url of the video, NOT the embedding code. DU's software recognizes video links and does the rest automatically.
truebluegreen
(9,033 posts)I've noticed that sometimes it works but I never knew why.
DamnYankeeInHouston
(1,365 posts)eggplant
(3,915 posts)It's a hell of a lot more complicated.
Think about it. If the world worked this way, species wouldn't go extinct. The planet would just fill up with, well, everything (except food, of course) until it was full. We wouldn't have massive die-offs due to plagues, volcanos, wars.
And for those people who will inevitably say, "Yes, but it's an analogy", fine. Then don't inject bad math into it. The world population growth *rate* is decreasing, not increasing as the video implies.
Don't brand me as a climate denier -- I am far from it -- but crap like this doesn't help the cause.
chervilant
(8,267 posts)denial message, you are richly illustrating your ignorance of exponential growth. Please revisit exponential functions. Look also at population growth expressions.
eggplant
(3,915 posts)Ok, I'm not sure who you are confusing me with, but this one time was my "every time". And your snarkier than thou response really isn't appreciated. You know nothing about me or what I know. I never expressed a lack of understanding about exponential growth. What I can tell you is that the current UN report on population growth says that the growth rate is decreasing. That would be the second derivative. If you'd like I can quote you back an obnoxious equation that has no context.
So I'm really not clear what sort of bug is up your ass, but don't take it out on me. I have no idea who you are or what you are talking about as to my supposed "denial" messages. Maybe you can either clear that up, or apologize and delete your message.
Have at it.
chervilant
(8,267 posts)Exponential Growth:
If N is the initial population and the growth rate is k then the population N at time t is:
N = N(sub o) e^kt , where k > 0
localroger
(3,634 posts)It's that more complex behavior you're talking about, a graph of how the "final" population varies as you alter the growth rate. Resource depletion is taken into account as one of the terms.
At low growth rates the population either reaches a stable value, or at higher growth rates oscillates between several metastable values.
At higher rates there are chaotic zones where the population is random within limits, or random except for semi-stable periods.
In all such models at some growth rate the curve stops, because the population reaches a value of zero during a negative swing and that is the final population.
I'll leave it as an exercise for you as to whether this means controlling growth might be wise.
eggplant
(3,915 posts)I never said anything about the merits of controlling population growth. Just that the model presented was wrong, and provided people holding opposing viewpoint something to point out as a way to discredit the more complex models.
Exponential growth is a terrible model. It's simply wrong. We don't live in a test tube with unlimited food where we never die off. Trying to equate our situation with that distracts from a productive conversation.
Even simplistic predator/prey models work better, and those don't take into consideration a host of relevant factors.
I'll choose to leave it as an exercise as to whether controlling growth is actually something that is possible.
localroger
(3,634 posts)Exponential growth is in fact the baseline model; there are modifiers, which are incorproated into the meta-model that generates the bifurcation fractal, but it all starts with exponential growth. The math revealed by the bifurcation fractal is seen all over the place in natural systems; management of deer populations which have to be culled by hunters, for example. The thing is the complex math wouldn't work if the simple math wasn't at its base. The fundamental problem is exponential growth. It cannot be sustained if the exponent outstrips the ability of natural death and other environmental factors to limit it. If the residual exponent after all such factors is added in is too high, ecosystem death results. There is no other possibility. The path to that will be extremely complex -- that's why they call it "chaos" theory -- but the math underlying it is now very solid.
If controlling growth is impossible then we are already the walking dead. The only question is just how bad the extinction event we are precipitating will be compared to the K-T or Permian events.
DamnYankeeInHouston
(1,365 posts)freedom fighter jh
(1,782 posts)And sneak in some politics.
Don't know how many students I got through to on either count. They all struggled with exponential growth.