We passed 400ppm the other day. It occasioned some hang-wringing, but no more than that. Many were at pains to point out that the milestone is strictly symbolic, that CO2 is steadily rising and likely will continue to do so, etc.
It's hard to know what will be required to shake us out of our torpor and motive human civilization to begin aggressively cutting fossil fuels. Something will, eventually. The beauty of this problem is that is will get progressively worse until we are ready to stop ignoring it. The unfortunate thing is that it will then continue to get worse for many decades after that.
Optimists abound, of course. Mark Lynas is still in the mix, accusing "catastrophists" of ignoring past human impacts on the environment:
As in his ill-considered attack on Diamond's "Collapse," however, Lynas is really rebutting a straw man: no one is arguing that humans' changing their environment is a new thing. Changing it in this way and to this extent is a new thing.
It's hard to tell from a Tweet, but Lynas seems to want to think that because changes happened in the past, and humanity survived it, that there's nothing to worry about in radically altering the climate upon which our survival depends. But of course, that is not at all what the historical record shows. The historical record is replete with mighty empires that turned fertile lands into deserts, tribes that hunted the large mammals to extinction (creatures they might have domesticated as farm animals or beasts of burden), societies that outgrew their water supplies or the available food supplies. Predictable disasters resulted.
The long history of people altering their environments is in part a history of people who carelessly or in ignorance damaged the productive capacity of the environments they inhabited. It's entirely in keeping with that history that we face similar choices today.
It's hard to know what will be required to shake us out of our torpor and motive human civilization to begin aggressively cutting fossil fuels. Something will, eventually. The beauty of this problem is that is will get progressively worse until we are ready to stop ignoring it. The unfortunate thing is that it will then continue to get worse for many decades after that.
Optimists abound, of course. Mark Lynas is still in the mix, accusing "catastrophists" of ignoring past human impacts on the environment:
Major land-use change paper from @erleellis et al in PNAS - the long Anthropocene, rebuttal to catastrophists: ecotope.org/people/ellis/p…
— Mark Lynas (@mark_lynas) May 7, 2013
As in his ill-considered attack on Diamond's "Collapse," however, Lynas is really rebutting a straw man: no one is arguing that humans' changing their environment is a new thing. Changing it in this way and to this extent is a new thing.
It's hard to tell from a Tweet, but Lynas seems to want to think that because changes happened in the past, and humanity survived it, that there's nothing to worry about in radically altering the climate upon which our survival depends. But of course, that is not at all what the historical record shows. The historical record is replete with mighty empires that turned fertile lands into deserts, tribes that hunted the large mammals to extinction (creatures they might have domesticated as farm animals or beasts of burden), societies that outgrew their water supplies or the available food supplies. Predictable disasters resulted.
The long history of people altering their environments is in part a history of people who carelessly or in ignorance damaged the productive capacity of the environments they inhabited. It's entirely in keeping with that history that we face similar choices today.