For starters, sea levels will rise by more than 70 meters. It could lead to a world substantially without naturally occurring ice. I think that a map of the world's land areas after a 70 meter rise in sea levels would be instructive. The conventional wisdom is that such a rise would take centuries. But with non-linear processes it could be significantly quicker. Even on a time scale of two centuries, that could be faster than much of the worlds existing fauna and flora could adapt.
While there would be extensive new littoral zones which are usually rich in marine life, much of that new area will be significantly polluted. There is likely to be much less arable land. The change would be of the kind that could best be illustrated by science fiction scenarios. Literally, most of life as we know it is likely to disappear. It is well worth serious efforts to slow and then reverse these trends. To me it would be worth it on aesthetic grounds alone. If sanity be culturally normative, then by the norms of this culture I claim insanity.
To some degree, we are already engaged in biochemical carbon capture: the generation of algal blooms through large scale injections of phosphates and other stuff in the seas and oceans. This is not a deliberate measure to roll back global warming, though. Anyway, the results are not pretty.
CSMonitor: Ocean 'dead zones' growing
Dead zones - areas of oxygen-depleted bottom waters - are spreading at an alarming rate in coastal waters, killing off huge amounts of marine life, a new study has found. In a paper published today in Science, Robert Diaz, a biological oceanographer at the Virginia Institute of Marine Science, and Rutger Rosenberg, a marine ecologist at Sweden's Göteborg University, identified more than 400 dead zones worldwide, affecting an area of more than 95,000 square miles, an area roughly the size of Oregon. The number and size of these dead zones are far greater than previously estimated. While some dead zones occur naturally, many are caused or exacerbated by chemical fertilizer runoff, fossil fuels, and rain. The fertilizer, which is rich in nitrogen compounds, is washed away from farmlands into rivers and ends up in the ocean. Burning fossil fuels produces airborne nitrogen oxides, which the rain washes into the ocean. The nitrogen compounds feed massive algae blooms. When the algae dies, it sinks to the ocean floor where it is consumed by microbes, which also consume oxygen in the process. As the oxygen is depleted, creating a condition called hypoxia, marine life that can flee does, and life that cannot - some fish but also clams, crustaceans, and other bottom dwellers - die of asphyxiation. At that point, microbes that live in oxygen-free environments begin to thrive and produce hydrogen sulfide, a poisonous gas. Most dead zones are seasonal, as the algae thrives in warm water.
In a paper published today in Science, Robert Diaz, a biological oceanographer at the Virginia Institute of Marine Science, and Rutger Rosenberg, a marine ecologist at Sweden's Göteborg University, identified more than 400 dead zones worldwide, affecting an area of more than 95,000 square miles, an area roughly the size of Oregon. The number and size of these dead zones are far greater than previously estimated.
While some dead zones occur naturally, many are caused or exacerbated by chemical fertilizer runoff, fossil fuels, and rain. The fertilizer, which is rich in nitrogen compounds, is washed away from farmlands into rivers and ends up in the ocean. Burning fossil fuels produces airborne nitrogen oxides, which the rain washes into the ocean.
The nitrogen compounds feed massive algae blooms. When the algae dies, it sinks to the ocean floor where it is consumed by microbes, which also consume oxygen in the process. As the oxygen is depleted, creating a condition called hypoxia, marine life that can flee does, and life that cannot - some fish but also clams, crustaceans, and other bottom dwellers - die of asphyxiation. At that point, microbes that live in oxygen-free environments begin to thrive and produce hydrogen sulfide, a poisonous gas. Most dead zones are seasonal, as the algae thrives in warm water.
I'm not an ecologist, but my guess would be that most of the top of the food pyramid comes tumbling off if we continue as we do, and a lot of ecosystems will go into disequilibrium, causing further extinctions. It's a very dangerous situation for the human species to be in. We're not technologically ready to survive as more than a rump if the ecosystem services we rely on fall down. The amount of social upheaval that will accompany this transition makes planning it impossible. I'm pessimistic about human survival in the face of catastrophic climate change.
It would be an unfathomable catastrophe.
Now, I don't expect +70m anytime soon, and by that I mean within the next million years. It would be too catastrophic not to take the most drastic of actions. "The womb that spawned that thing is fertile yet"
Mig provided a link that showed the global effects of sea level increases up to 7 meters. I believe that such a link that showed the effects of a 70 meter rise might be useful to show people what their great, great grandchildren, if any, could be inheriting. Just because we will all be dead does not mean that we can abandon concern for posterity. Perhaps one of the benefits of increased life span could be a heightened concern for future generations, more of whom some of us might see. If sanity be culturally normative, then by the norms of this culture I claim insanity.
