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Effect of humans on the environment

  1. Dec 12, 2009 #1

    Evo

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    This came up in a thread in Politics, and Integral and I thought it would be an interesting discussion on the impact on climate change.

    Livestock, agriculture and deforestation have been a major issue, but it doesn't seem to be as popular in the media.

    http://news.bbc.co.uk/2/hi/7600005.stm

    There was a report in 2006 "Livestock’s Long Shadow –Environmental Issues and Options." The full report here http://www.fao.org/docrep/010/a0701e/a0701e00.HTM

    The condensed version here http://www.fao.org/newsroom/en/news/2006/1000448/index.html
     
    Last edited: Dec 26, 2009
  2. jcsd
  3. Dec 24, 2009 #2
    Re: Effect of ranching on the environment

    Polllution (increase in the level of carbon over the years ) to me is the major player which brings climate change on earth.
     
  4. Dec 26, 2009 #3

    Evo

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    I will be adding to this thread as time permits. I hope we can get some discussion started.

    http://atlas.aaas.org/index.php?part=1
     
  5. Dec 26, 2009 #4

    Xnn

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    It's true that agricultural output doesn't seem to get much press. My impression is that people who wish to "save the planet" can't admit that there is a positive to the warming and those who are sure "it's all a conspiracy", won't ever admit to anything anyways. So, along we go.

    Anyhow, here's the science backed statement with medium to low confidence:

    http://www.ipcc.ch/pdf/assessment-report/ar4/wg2/ar4-wg2-chapter5.pdf
     
  6. Dec 26, 2009 #5

    Evo

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    According to a recent poll of SUNY professors, overpopulation is the #1 environmental concern. So I am surprised that politicians and the press haven't made this an issue, especially after the UN came out with such an urgent warning of the consequences of overpopulation on the environment. But more on that to come.

    http://www.newswise.com/articles/view/551353
     
  7. Dec 26, 2009 #6
    From the book Ishmael

     
  8. Dec 26, 2009 #7

    Evo

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    I read the plot of the book the other day after you mentioned it. I'm getting it, Ishmael encouraged me to revisit this thread and add to it. I think it's very important that what the overpopulation of humans is doing to this planet be addressed.
     
  9. Dec 26, 2009 #8

    Evo

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    Unfortunately there was a huge backlash against the UN for stating that overpopulation was a problem and they were forced to drop it.
     
  10. Dec 27, 2009 #9

    OmCheeto

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    I remember the day you mentioned this thread Evo. I'm not surprised it took someone 12 days to respond. Where does one begin.

    I think the problem with discussing this idea, is that most immediate solutions are politically unacceptable. One child per family is looked upon with either disdain or disbelief. Two children per family would simply keep us where we are at. And we are in a stinking mess as it is, IMHO.

    I can recall, that around the time I was 15, that there was much talk of overpopulation, and I sat down in front of my mothers mechanical calculator and started plugging in the 1 child per family numbers; just for fun of course. I wanted to see how long it would take to get back to 2 people. The number I recall was 720 years. Though today I come up with 600, so I'm sure I was much more thorough in my world almaniacal number crunching as a youngster.
    Anyways, my number crunching today says that the one child per family rule, world wide, would reduce the population to 1 billion in about 78 years. So with some worldwide education, I'm sure we can make a dent.

    I've done a bit of studying of the era this evening, and discovered what probably caused my interest back then:
    I remember Rockefeller was a one child advocate, and if I recall correctly, he promoted a tax break for only the first child. Quite the :bugeye: for people with more than 1 kid, which was probably everyone at the time. I was quite the gloater when China announced their one child policy a few years back, as it had mysteriously become my idea.

    But yes, our effect on the planet is pandemic. Deforestation, pollution, collapse of the fisheries, atmospheric alterations, to name a few. All can be directly linked to overpopulation.

    Looking at my world population numbers, I ran across the year 2525, which is when we will reach a hypothetical 100 quadrillion people(20 people per ft^2, including oceans), at our current growth rate. And it reminded me of that old song, regarding which on wiki someone posted the following:

    Being a techno-geek, I can only partially agree. Technology after all, developed the solution to the overpopulation problem 50 years ago, in the form of a http://en.wikipedia.org/wiki/Combined_oral_contraceptive_pill" [Broken].


    ps. I never had kids. pat on back, pat on back.
     
    Last edited by a moderator: May 4, 2017
  11. Dec 31, 2009 #10
    Who am I to argue with distinguished professors but I am not sure if I agree with this Evo.

    Overpopulation where it is most prevalent (ie. in developing/third world nations) has a very limited impact on the enviroment - it is these 5 billion people who are effectively subsidising our extravagent, totally unsustainable lifestyles in the West. A huge chunk of the global populations can't afford meat, don't have access to electricity, don't drive cars, etc.

    And our population is, as OmCheeto points out, pretty much constant (if not in decline).

    PS Ishmael is very though provoking read!
     
    Last edited by a moderator: Apr 24, 2017
  12. Dec 31, 2009 #11

    Ivan Seeking

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    We have cut waaasaaay back on our beef consumption. I still love a good BBQ steak or prime rib from time to time, but only four or five times a years anymore. Beyond that, I might use about 12 Lbs of ground sirloin for tacos each year.

    Coming soon: The McSyntheMac

    http://www.yucommentator.com/news-brief/synthetic-meat-1.995629#4

    Also, twice I have posted the comment that the most important thing one can do to reduce their carbon footprint, is to not reproduce.

    We never had kids.
     
    Last edited: Dec 31, 2009
  13. Dec 31, 2009 #12

    Ivan Seeking

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    ...so the way that I see it, Tsu and I are entitled to live in a perpetual CO2 orgy. :biggrin:

    Heh, cap and trade for offspring!
     
  14. Jan 1, 2010 #13
    I was concerned about overpopulation, but I was recently reading Stewart Brand's new book "Whole Earth Discipline" which has a chapter on population. He mentioned that 59 countries have birth rates below replacement levels. The UN is currently projecting the whole world will drop below replacement level by 2045 at a population of 9 billion. Brand thinks that number is too high and estimates it will be closer to 8 billion. This is pretty startling change for Brand who was a supporter of Paul Ehrlich back in the seventies.

    The numbers for Mexico were quite striking. 6.5 births per woman in the 70s down to 2 in 2008 and still dropping.

    This seems to be a product of urbanization. Over half the people in the world live in cities now and that may increase to 80% by 2050. It seems that all over the world, when women move to the city they lose interest in having children.
     
  15. Jan 1, 2010 #14

    OmCheeto

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    Overpopulation can be interpreted in different ways of course. A nations ability to provide a decent standard of living to it's populous through sustainable, self sufficient means, would indicate that the region is not overpopulated. India comes to mind. I told my friend from Hyderabad that his description of India, and it's method of sustaining such a large population, could be a good model for the rest of the world over the next 100 years. Though the collision of east and west has lately been causing some disastrous results.
    I would consider electricity and cars to be luxuries, and not necessary to the happiness of any individual. Prior to 100 years ago, the entire planet lived without either. We've simply grown used to them. I for one can't imagine living without them. Which is why I choose to spend most of my free time working towards a zero carbon footprint, rather than just whining about it.

    And as for meat, if a local population can't sustain a bunch of chickens and goats, then they are overpopulated.
    I don't recall saying that, but looking at some http://www.google.com/publicdata?ds...+population+growth#met=sp_pop_grow&tdim=true", it would appear, that if the trend continues, we will have zpg by August 17th, 2052 at 4:31 in the afternoon. (Based on a linear interpolation of the graph between 1971 and 2008)

    A good thing no doubt. We really need to slow down and figure out how to take care of the people we've already got around us. A http://www.nytimes.com/2009/09/10/world/10child.html" [Broken] of 1 out of 8 children dying before reaching the age of 5 in less developed countries is very sad, to say the least. But this trend is fortunately on the decline also.
     
    Last edited by a moderator: May 4, 2017
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