06-28-2006, 05:52 AM
The "propaganda film" has some info along those lines....
Since the "current-condition" measurements first started about 50 years ago, they have been performed in remote areas of the Pacific in order to lessen the influence of factors of the land masses.
One of the things addressed in the film is that there is a yearly CO2 level cycle, easily visible on the graph as a zig-zag. What causes this cycle? Turns out that the Northern Hemisphere is better (so far) at mitigating CO2 buildup, because it has much more arable land mass than the Southern Hemisphere. It has a lot more vegetation (trees), and it reduces the CO2 levels each year as the sun provides more heat to the Northern Hemisphere (during northern summer). During northern winter, the sun gives more heat to the Southern hemisphere, which has less landmass, so less vegetation, so less CO2 mitigation.
This doesn't answer your questions, and you may have known this stuff already, but I thought that it was worth noting that the film does talk about some hemispherical issues.
The zig-zag, to me, shows that human activity is DEFINITELY affecting CO2 levels, through deforestation alone. (This isn't anything the movie says, but my own conclusion.) If there's that much difference just from the differing land masses, then the effects of deforestation should not only be definite, but measurable through mathematical inference. (Too lazy to find out if anyone has done this, tho.)
Regarding the film, though, one should remember that it is difficult to walk the line between too little and too much information (do we really want to sit through 498 conclusions??), and to keep it simple so that most people can understand the issue and yet not be condescending. (There is one cartoon used -- little girl with ice cream -- that's supposed to be a joke because it's so stupid, but it's just, well, stupid. It's suposed to be stupid, but I couldn't help but thinking, "that's stupid". You'll see what I mean. )
-V
Manager, Garden Gnome Team
The Forsaken Inn
Quote:The consideration that this article raises in my mind isn't that global warming must not be happening, but perhaps our data are skewed. Are the studies/effects predominantly concerned with the changes in the Northern Hemisphere? That is where most of the Earth's population lives, and where the bulk of the land mass is. How does that imbalance influence global climate? Are average temps and weather patterns in the southern hemisphere trending in the same direction as the Northern Hemisphere? How much cross flow is there in air masses between hemispheres? The heat output in the Northern Hemisphere, based on human population density, would be, I guess, about an order of magnitude greater than in the Southern Hemisphere.The "propaganda film" has some answers to that, at least in terms of CO2 measurements.
Since the "current-condition" measurements first started about 50 years ago, they have been performed in remote areas of the Pacific in order to lessen the influence of factors of the land masses.
One of the things addressed in the film is that there is a yearly CO2 level cycle, easily visible on the graph as a zig-zag. What causes this cycle? Turns out that the Northern Hemisphere is better (so far) at mitigating CO2 buildup, because it has much more arable land mass than the Southern Hemisphere. It has a lot more vegetation (trees), and it reduces the CO2 levels each year as the sun provides more heat to the Northern Hemisphere (during northern summer). During northern winter, the sun gives more heat to the Southern hemisphere, which has less landmass, so less vegetation, so less CO2 mitigation.
This doesn't answer your questions, and you may have known this stuff already, but I thought that it was worth noting that the film does talk about some hemispherical issues.
The zig-zag, to me, shows that human activity is DEFINITELY affecting CO2 levels, through deforestation alone. (This isn't anything the movie says, but my own conclusion.) If there's that much difference just from the differing land masses, then the effects of deforestation should not only be definite, but measurable through mathematical inference. (Too lazy to find out if anyone has done this, tho.)
Regarding the film, though, one should remember that it is difficult to walk the line between too little and too much information (do we really want to sit through 498 conclusions??), and to keep it simple so that most people can understand the issue and yet not be condescending. (There is one cartoon used -- little girl with ice cream -- that's supposed to be a joke because it's so stupid, but it's just, well, stupid. It's suposed to be stupid, but I couldn't help but thinking, "that's stupid". You'll see what I mean. )
-V
Manager, Garden Gnome Team
The Forsaken Inn