Effect of humans on the environment

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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.

How come it seems that possible change in agriculture output is never mentioned by most people in global warming debates, am I missing something?
Livestock, agriculture and deforestation have been a major issue, but it doesn't seem to be as popular in the media.

Rajendra Pachauri, who chairs the Intergovernmental Panel on Climate Change (IPCC), will make the call at a speech in London on Monday evening.

UN figures suggest that meat production puts more greenhouse gases into the atmosphere than transport.
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
 
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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.
 

Evo

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

Humans are perhaps the most successful species in the history of life on Earth. From a few thousand individuals some 200 000 years ago, we passed 1 billion around 1800 and 6 billion in 1999. Our levels of consumption and the scope of our technologies have grown in parallel with, and in some ways outpaced, our numbers. [Add]

But our success is showing signs of overreaching itself, of threatening the key resources on which we depend. Today our impact on the planet has reached a truly massive scale. In many fields our ecological "footprint" outweighs the impact of all other living species combined.[Add]

We have transformed approximately half the land on Earth for our own uses -- around 11 percent each for farming and forestry, and 26 percent for pasture, with at least another 2 to 3 percent for housing, industry, services and transport [1]. The area used for growing crops has increased by almost six times since 1700, mainly at the expense of forest and woodland [2].[Add]

Of the easily accessible freshwater we already use more than half. We have regulated the flow of around two thirds of all rivers on Earth, creating artificial lakes and altering the ecology of existing lakes and estuaries [3].[Add]

The oceans make up seven tenths of the planet's surface, and we use only an estimated 8 percent of their total primary productivity. Yet we have fished up to the limits or beyond of two thirds of marine fisheries and altered the ecology of a vast range of marine species. During this century we have destroyed perhaps half of all coastal mangrove forests and irrevocably degraded 10 percent of coral reefs.[Add]

Through fossil-fuel burning and fertilizer application we have altered the natural cycles of carbon and nitrogen. The amount of nitrogen entering the cycle has more than doubled over the last century, and we now contribute 50 percent more to the nitrogen cycle than all natural sources combined. The excess is leading to the impoverishment of forest soils and forest death, and at sea to the development of toxic algal blooms and expanding "dead" zones devoid of oxygen.
http://atlas.aaas.org/index.php?part=1
 

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:

In mid- to high-latitude regions, moderate warming benefits
crop and pasture yields, but even slight warming decreases
yields in seasonally dry and low-latitude regions (medium
confidence).


Modelling results for a range of sites find that, in mid- to highlatitude
regions, moderate to medium local increases in
temperature (1-3ºC), along with associated carbon dioxide
(CO2) increase and rainfall changes, can have small beneficial
impacts on crop yields. In low-latitude regions, even moderate
temperature increases (1-2°C) are likely to have negative yield
impacts for major cereals. Further warming has increasingly
negative impacts in all regions (medium to low confidence)
[Figure 5.2]. These results, on the whole, project the potential
for global food production to increase with increases in local
average temperature over a range of 1 to 3ºC, but above this
range to decrease
http://www.ipcc.ch/pdf/assessment-report/ar4/wg2/ar4-wg2-chapter5.pdf
 

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.

Worst Environmental Problem? Overpopulation, Faculty Says

Overpopulation is the world's top environmental issue, followed closely by climate change and the need to develop renewable energy resources to replace fossil fuels, according to a survey of the faculty at the SUNY College of Environmental Science and Forestry (ESF).
http://www.newswise.com/articles/view/551353
 

Evo

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From the book Ishmael
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.
 

Evo

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The Royal Society and the National Academy of Sciences on Population Growth and Sustainability

World population is growing at the unprecedented rate of almost 100 million people every year, and human activities are producing major changes in the global environment. If current predictions of population growth prove accurate and patterns of human activity on the planet remain unchanged. science and technology may not be able to prevent either irreversible degradation of the environment or continued poverty
for much of the world.

The following joint statement, prepared by the Officers of the Royal Society of London and the United States National Academy of Sciences, reflects the judgement of a group of scientists knowledgeable about the historic contributions of science and technology to economic growth and environmental protection. It also reflects the shared view that sustainable development implies a future in which life is improved worldwide through economic development, where local environments and the biosphere are protected, and science is mobilized to create new opportunities for human progress.

Through this statement, the two academies wish to draw attention to these issues and to stimulate debate among scientists. decision makers. and the public. In addition. the two institutions, in cooperation with other academies, propose to organize a scientific conference in early 1993 to explore these issues in detail.

THE REALITY OF THE PROBLEM

Scientific and technological innovations, such as in agriculture, have been able to overcome many pessimistic predictions about resource constraints affecting human welfare. Never. the less, the present patterns of human activity accentuated by population growth should make
even those most optimistic about future scientific progress pause and reconsider the wisdom of ignoring these threats to our planet.

Unrestrained resource consumption for energy production and other uses, especially if the developing world strives to achieve living standards based on the same levels of consumption as the developed world, could lead to catastrophic outcomes for the global environment.

In places where resources are administered effectively, population growth does not inevitably imply deterioration in the quality of the environment. Nevertheless, each additional human being requires natural resources for sustenance, each produces by-products that become part of the ecosystem, and each pursues economic and other activities that affect the natural world. While the impact of population growth varies from place to place and from one environmental domain to another, the overall pace of environmental changes has unquestionably been accelerated by the recent expansion of the human population.

http://dieoff.org/page7.htm
Unfortunately there was a huge backlash against the UN for stating that overpopulation was a problem and they were forced to drop it.
 

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:
http://www.population-security.org/mumf-94-03.htm
circa 1969
The Rockefeller Commission Report and the NSSM 200 response are arguably the most important documents on overpopulation ever written. Our country and the world would be very different today if the recommendations in these documents had been implemented.
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:

a world doomed by its passive acquiescence to and over-dependence on its own overdone technologies
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.
 
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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
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!
 
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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

Researchers at the Netherlands' Eindhoven University of Technology have, for the first time, successfully produced laboratory-grown steaks. The process, though complex, involves animal myoblasts (basically, stem cells for muscles) – noninvasively extracted from adult livestock.

Then, when cultivated in a nutrient medium that includes products derived from unborn bovine fetuses – obviously, very invasively extracted – these cells are capable of rapidly dividing to form new muscle tissue...
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.
 
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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!
 
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.
 

OmCheeto

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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.
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.
http://infochangeindia.org/200812167535/Agriculture/News/NCRB-claims-46-farmers-commit-suicide-every-day-in-India.html" [Broken]
A huge chunk of the global populations can't afford meat, don't have access to electricity, don't drive cars, etc.
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.
And our population is, as OmCheeto points out, pretty much constant (if not in decline).
I don't recall saying that, but looking at some http://www.google.com/publicdata?ds=wb-wdi&met=sp_pop_grow&tdim=true&q=world+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.
 
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