[froggy]

Great article, but it might be more complete with a mention of the rising acidity of the oceans and how as the ph drops, many of the shelled animals at the bottom of the ocean food chain who depend on their shells for protection will not be able to form shells (the acidity eats away at the calcium carbonate) making a whole category of the food chain susceptible to extinction.

I appreciate the optimism in this article that humans are "on the right path", but the bottom line is humans have already caused a major disruption to the biosphere via carbon emissions, and the carbon emissions are still increasing which will have an effect of ocean life, thus humans.

I'd like to see more thought going into "helping people live better lives while living in balance with nature", rather than "We can expand the human species to 20 billion - let's do it!"

[zeteo]

>>I'd like to see more thought going into "helping people live better lives while living in balance with nature"<<

Nature is inherently unbalanced:

http://en.wikipedia.org/wiki/Balance_of_nature#Counter-argum...

For instance, the biosphere has managed to royally mess itself up at least once:

http://en.wikipedia.org/wiki/Great_Oxygenation_Event

(see http://en.wikipedia.org/wiki/Snowball_Earth#During_the_froze... for some of the effects)

[bellaire]

Aside from semantic arguments about what "balance" means, it's true that nature is a state of constant change.

When people talk about sustainability, they're acknowledging that humans can have an impact on nature, or more to the point, on our ability to sustain our own species. It's pretty fair to say that no matter how royally we mess things up, the biosphere will probably eventually "recover"... it'll simply be drastically different.

So, given that we can be agents of change in nature, it's not unreasonable to consider not only whether we can simply survive as a species, but whether we can or should show restraint with respect to the effects we have on the rest of the natural world.

McCarthy seems to be of the opinion that efforts thus far have been not just ineffective, but actually harmful to ourselves. That is to say, we're better off allowing progress to happen naturally without "artificially" trying to mitigate it. Others would appear to disagree, or at least still consider the pursuit of sustainability, in the popular sense, worthwhile.

[zeteo]

>>It's pretty fair to say that no matter how royally we mess things up, the biosphere will probably eventually "recover"

That's not what I've argued, please read my comment again. On the contrary, my point is that the biosphere is a very unstable system, and there are no guarantees of "recovery" from anything. It can kill itself on a whim, and has come close to doing so in the geological past. In the long run, nature is a chaotic, not a homeostatic system, and "balance with nature" is an oxymoron.

[bellaire]

>> It can kill itself on a whim, and has come close to doing so in the geological past.

I'm not sure what you mean by "close to" killing itself. In the geologic past, life itself has survived rapid toxic oxygenation, the complete freeze-over of the planet's surface, and the complete sterilization of surface life including boiling off the world's oceans. Microbial life still survived that last one in insulated rock miles below the surface. What catastrophe are you proposing we could induce that would do worse?

>> In the long run, nature is a chaotic, not a homeostatic system, and "balance with nature" is an oxymoron.

Now I invite you to read my comment again.

[zeteo]

I've invited you to read my comment again because I felt you were mis-representing my point. Regarding the rest,

http://en.wikipedia.org/wiki/Survivor_bias

http://en.wikipedia.org/wiki/Life_on_mars#Liquid_water

Considering that there have been very severe extinction events in the past; that the best evidence we have for Mars indicates it sustained life in the past, and then lost it; it is special pleading to argue that life on Earth, or at least multi-cellular life, has some hypothetical property that will make it go on forever. On the contrary, the multitude of documented dangers, the suddenness and magnitude of shifts in the paleobiological record indicate that life on Earth may yet go completely extinct within a relatively short geological time span, even were all humans to commit suicide today.

[bellaire]

I see what you are saying, but I don't agree. You are reversing the evidence in your assertions. There is no evidence that life has existed in the past on Mars. If there were, that would be fantastic, and many people believe such evidence will be forthcoming, but as of right now, there is none that is accepted in the mainstream.

As to your other point, the very fact that life on Earth has come close to extinction, and yet survived, so very many times indicates that there is an empirical (not theoretical) basis for my claim that life (in some form) tends to bounce back. The mechanism is the fact that bacterial and archael life forms live deep within insulated areas of Earth's crust and retain relatively (geologically speaking) modern genes for traits such as aerobic respiration. Survivorship bias does not imply that in some situations there are no survivors, that is a misapplication of the idea.

Now, it's certainly possible that life could be extinguished in a short geologic time span, that I don't refute. And of course, in around a billion years the sun's total radiative output will make life all but impossible on Earth's surface. But in the mean time, evidence suggests life is incredibly hardy.

I suspect, anyway, that we are talking at cross-purposes. The topic was sustainability vis a vis human activity. You rightly point out that we are not in total control, that things can go awry without our intervention. Nature is indeed a chaotic system. However, I suspect you do not disagree that we can choose to avoid certain paths that would inevitably lead to our own destruction. We probably can't avoid all of them, as we are not omniscient, but my main point is that it behooves us to think about it, and to attempt to act responsibly, not in a sense of maintaining the natural state of the world as a static equilibrium, but merely to survive as best we understand how.

[lloeki]

There's quite a difference between an unmonitored event and shooting oneself in the foot. We're a technologically capable, conscious, foreseeing species; things having happened back when we were not are not an excuse to behave today as mere beholders, or worse, as levers of the system instability.

[zeteo]

My comment didn't say anything about how we should behave; I was merely pointing out that nature is inherently unbalanced.

[RodgerTheGreat]

A little knowledge can be a dangerous thing. We have some technology, we have some understanding of how our biosphere works and we have some ability to effect change in our environment. The earth is a big, complicated machine- are you confident that we can predict the long term outcome of our actions when we try to "fix" things?

[brc]

rising acidity = lessening alkalinity. Let's be more precise and use more benign statements.

The Ocean Acidification scare falls directly under the types of scares this article talks about. It is unproven, untested and not subject to high levels of certainty. Talk of changing the entire ocean pH fails to cover the fact that there is no one set pH level for all the oceans as whole.

Further to that, shellfish and crustaceans are a pretty ancient life form, and have existed throughout many different levels of atmospheric co2.

All I'm saying is that the article advises a data-driven approach to these matters, and the data on the ocean decreasing pH theory is still full of a lot of 'maybe, possibly and if' disclaimers.