Chris Wood
Friday April 30th, 2010

Ruining Our World

The last 10,000 years have seen a fairly nice stable climate on Earth, during which the human race has expanded from one million to 7000 millions. This period is called the Holocene. We are now entering the Anthropocene, which due to humans will not be so comfortable. The “New scientist” of 27.02.2010 reported on a conference of 28 environment experts, concerning how close we are to ruining things completely. Besides climate, they considered eight other aspects. The following is a summary of their tentative conclusions, with some comments from me. It starts with the only positive case and finishes with the most urgent.

Ozone

The stratospheric ozone level is about 5% better than we need to prevent serious radiation damage, and is improving. The situation was saved just in time.

Acid Oceans

When the oceans get too acid, animals will not be able to form shells, and will die. This affects corals, and many other animals of various sizes. Atmospheric CO2 affects this. Some seas may reach this stage by 2050. It is hard to say just how terrible the effect will be.

Fresh Water

World-wide, about two thirds of available fresh water is being “used”. Most of the rest will be needed by 2050, because of population growth. Climate change may well reduce precipitation.

I understand that the main use is for agriculture. We shall have to change our food (e.g. less meat, crops that need less water), or eliminate population growth.

Biodiversity

The annual extinction rate is at least 100 per million species. We need to get it down to 10 per million. The current rate of extinction is similar to that during the 5 or 6 earlier mass extinctions since life on earth began. It will get worse if the climate heats up. Biotopes with few species tend to be unstable.

The target rate is highly arbitrary. This is the aspect where we are furthest beyond the target, and the one where we know least about the effect on mankind. I see biodiversity as an ethic in its own right, alongside pro-human ethic. If, as seems likely, mankind wipes itself out, biodiversity will be needed to restart evolution towards intelligence.

Nitrate

Too much fertiliser in the water causes a bloom of simple organisms. When they die, their decomposition takes oxygen out of the water, leaving it stinking and “dead”. This has already happened to some lakes and rivers; the Baltic and Mediterranean are endangered. Too much nitrate in the soil is similarly bad. Nitrates also contribute to acid oceans. A century ago, German scientists developed a process for producing nitrate from air. Three or four times as much nitrate is being produced as can be recycled. How long can this go on, before the oceans are seriously affected? We can hardly reduce use of fertilisers, while still feeding the world.

I think this may remain only a local problem. With so much nitrate in the oceans, will not organisms develop that use it as a source of oxygen? Genetic engineering may help. The oceans should be farmed better as a potential source of much more food and fuel than the land. The plants and animals involved must be kept near the surface, and their salt content needs to be reduced somehow. Many of the small animals near the start of the food chain have shells that will be affected by acidity (see above). Why is so little being written about all this? Is anybody working on it?

Phosphates

Phosphate fertilisers produce local problems similarly to nitrate. The quantities are much less, due to the availability and cost, and can be recycled at present.

I think recycling takes place largely due to fishing by humans and birds.

Agricultural Land

Of land that is not snow covered, 12% is used for agriculture. This should not go above 15%. But it will probably reach this value by 2050.

I was surprised how low these figures are. Of course a lot of land is desert, which is no use without (fresh) water, (see above). Other land is just rock. Erosion, pollution and rising see levels are reducing fertile land. Continental drift very gradually converts the muck under the oceans into land. Before agriculture started, this balanced erosion. Can we restore the balance in the next few hundred years?

Aerosols

The atmosphere in some parts of the world is full of unhealthy aerosols. They cause millions of human deaths pro year. It is unclear how bad this will/can get.

Chemicals

About 100,000 chemical substances are produced and used. Production and use of these generate many further compounds. Some of these may be responsible for various serious diseases.

Obviously some of the worst cases are known (DDT, dioxin). Population control would not be a problem if many others had terrible effects. I think there is no great general problem. But there is a constant slight chance of a new substance wiping out mankind. Why did most dinosaurs die out while mammals survived? Genetic engineering is the main danger, although only a small one.

Climate Change

“This is the big one”. Atmospheric CO2 is already 10% above the “safe” limit and is increasing! The trouble is that there is delayed positive feedback; we do not know how strong. Melting Arctic pack-ice will reduce the Earth’s albedo. Warming tundra will release the greenhouse gas methane. Atmospheric water-vapour, another greenhouse gas, will increase.

This committee avoids a concrete prediction, but they seem to fear a 6 degree temperature rise by 2100. This would have dramatic effects.

My Conclusion

I believe it would be possible to support the current Earth population level for the next hundred years, but I do not believe it will happen! As well as the above problems, remember how many countries have nuclear weapons.

4 Kommentare zu “Ruining Our World”

  1. Tweets die IF-Blog » Blog Archiv » Wie wir unsere Welt zerstören erwähnt -- Topsy.com (Sunday May 2nd, 2010)

    […] Dieser Eintrag wurde auf Twitter von Roland Dürre und Claudia Brehm, Claudia Brehm erwähnt. Claudia Brehm sagte: RT @RolandDuerre: Chris Wood hat geschrieben: http://bit.ly/9FU960 Wie wir unsere Welt zerstören #traurig #unverantwortlich #katastrophal IF-Blog.de […]

  2. JUS (Monday May 3rd, 2010)

    Und wiedermal der Klimawandel.

    Zitat:
    “Dieses Gremium macht keine konkreten Aussagen, aber es scheint, als fürchten sie eine Erderwärmung um 6 Grad bis zum Jahr 2100. Die Folgen davon wären dramatisch.”

    Welches Gremium ist gemeint? Und keine konkreten Aussagen kennen wir schon von der Politik, aber was von den Aussagen der Wissenschaftler zu halten ist (von denen eigentlich Aussagen kommen sollten), ist sehr schön auf Spiegel online nachzulesen, fast alle sind nichts als Zuarbeiter der Umweltverbände oder der Industrie, die jeweils die Sau in anderer Richtung durch’s Dorf treiben.

    http://www.spiegel.de/wissenschaft/natur/0,1518,688175,00.html

    JUS

  3. Chris Wood (Tuesday May 4th, 2010)

    I cannot remember what else New Scientist wrote about these 28 experts. The most careful predictions say that we must expect at least plus two degrees. Of course there are factors that may make it much worse, particularly if nothing is done about it.
    There is a drive to develop electric cars, because the Chinese are worried about the air in their cities. But electric cars will be worse for the climate than conventional cars, as long as the extra electricity comes from coal power stations.

  4. Chris Wood (Thursday August 19th, 2010)

    HELIUM
    Reserves of helium, (incidentally the second commonest element in the universe), will run out in about 25 years. Helium is used for balloons of all sizes and for diving, and is most vitally needed for cryogenic applications. It forms by radioactive decay inside the earth, and seeps up into the same formations where gas (methane) is found. There it comprises 0% to 2% of the gas. USA has stockpiled tons of it, but is now selling it off much too cheaply. When stocks run out, helium can be extracted from the atmosphere. But the energy needed for this will mean that it will cost $100 to fill a party balloon.

Kommentar verfassen

*