Catastrophic Climate Change: We Caused It; We're Going to Have to Fix It.
Algae Blooms
Algae blooms are growing in size, geopgraphic distribution and duration. One factor in this is the
rising average global temperature. However, algae is not just thriving on planetary warming, it is also
contributing to climate change in a vicious circle (or positive feedback loop). Algae grows as seasonal
temperatures rise, and then die off when sunlight diminishes and colder weather returns. While the blooms
are forming, they reduce the amount of light getting into the water, which reduces growth of the
aquatic weeds which provide habitat for many kinds of fish. And while they consume carbon dioxide from
the air during their growth, they are also associated with reducing oxygen levels in the water.
But, the biggest damage comes when the algae blooms die off. The vegetative mass sinks, and decomposes
under water - an anaerobic zone. That means, instead of just giving back the carbon dioxide it has
consumed (which would happen in an aerobic environment like a compost pile), the decomposing algae
produces methane - a greenhouse gas 56 times more potent than carbon dioxide. If our objective is
to reduce the impact of greehouse gas emisisons to maintain a survivable planet, replacing carbon dioxide
with methane is not a good substitution. We need to reduce algae bloom formation (by reducing nutrient
supplies and cooling the water), and when they do appear, we need to remove the blooms from the water
so they can decompose in air or put the biomass to other beneficial use.
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