Each year, between the burning of fossil fuels and the clearing of old growth forests, humans put about 10 petagrams of carbon dioxide (CO2) into the atmosphere. A petagram is one quadrillion grams. Ten petagrams is equivalent to the mass of Halley’s comet, to put it in perspective.
Having a steady amount of CO2 in the atmosphere is necessary to ensure stable average temperatures across the globe. Ideally, carbon output and uptake would balance out, as it has for centuries. But since the industrial revolution, human activities have disturbed that equilibrium, resulting in excess atmospheric CO2. As a greenhouse gas, CO2 prevents heat from escaping Earth’s surface through the atmosphere. Most of the scientificMassive Open Online CoursesMassive Open Online Courses community believes this is the primary cause of global climate change.
Fortunately, the ocean helps mitigate the effects of that excess CO2, absorbing anywhere from a quarter to a third of our carbon emissions. Some of the CO2 dissolves into the cold waters of the polar seas. But a large portion is removed from the atmosphere by tiny organisms most people know nothing about.
Those organisms are phytoplankton – microscopic algae that are the basis for the entire food web in the ocean. Phytoplankton are like the grass of the sea. They can be found in virtually any body of water that is exposed to sunlight. They photosynthesize, turning carbon dioxide into sugar in order to grow, and simultaneously produce oxygen. In fact, half the oxygen in our atmosphere was made by phytoplankton.
Read more at: Phys.org