@georgeob1,
georgeob1 wrote:
livinglava wrote:
The carbon cycle is actually very similar to the water cycle. Water rains down and fills up underground aquifers. Likewise, carbon gets absorbed by trees, plants, and animals and gradually builds up concentrated underground reserves, like ground water except it is carbon-based fossil fuels.
Yet another shallow and incorrect interpretation of basic facts. The carbon cycle is profoundly different from the water cycle in that CO2 absorbed by the oceans as carbonic acid later combines with dissolved calcium to form limestone where it is sequestered.
Are you trying to undermine the analogy without acknowledging the similarities that make it valid?
Not every drop of rain or snow that forms as precipitation makes it underground to replenish aquifers. A lot of rain re-evaporates and falls many times before some fraction of it seeps deep enough underground to be stored long-term. This is also true for carbon absorbed on the surface. Most leaves, wood, animal droppings, etc. will compost at the surface and thus 're-evaporate' as CO2. A small amount, however, will stabilize underground and eventually be compacted/processed into fossil fuels by extremely long geological processes.
What humans are doing to the carbon cycle is akin to turning the land into a desert that is incapable of precipitating water and capturing it underground. CO2 can only precipitate if there is living ground-cover, and developed land removes and fails to replace the vast majority of it. Next time you are in a city, take a look around at the ornamental trees and shrubs and ask yourself how much coal, oil, and natural gas those will render in the next few 100,000s of years.
As for what you're saying about carbonic acid in the oceans combining with dissolved calcium to form limestone, what's your point with that? Are you claiming that process can continue without plants absorbing the carbon? If so, why have CO2 levels become elevated in the last few centuries instead of the oceans just absorbing all the excess CO2?
It seems obvious to me that if CO2 levels are rising, that CO2 is being produced faster than it is being naturally absorbed. The next question that follows from that is how much of that glut in atmospheric CO2 is due to excess production and how much is due to reduced absorption? I think the reduced-absorption capacity of the land is the most overlooked factor because once land is cleared and developed with less trees, we just take it for granted as being a shopping center, parking lot, highway, residential neighborhood, etc. instead of looking at it in terms of how much living forest is missing from it.
We only look at deforestation in terms of new instances of land-clearing. We don't think about land that was cleared decades, centuries, or millennia ago as 'deforested,' because we just think of them as being what they have become established as since their development.
