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The “Planetary Boundaries” image graphically interprets research conducted by the Stockholm Resilience Centre.
Nature has many tipping points or boundaries as the Planetary Boundaries image indicates. These boundaries represent the safe operating limits of the Earth’s capacity to regulate itself in a way comfortable for humans. When human activities, combined with other non-human caused factors, exceed these boundaries, a stable state is disrupted. The Planetary Boundaries formulation determines what researchers believe to be the tipping points for a variety of phenomena which humans are warned against exceeding. The image shows human activity’s impact has gone beyond the boundary line for both bio-diversity loss and nitrogen/phosphorous loading. It also shows that human impact is in danger of exceeding recommended tipping points for ocean acidification and freshwater use. As for items such as atmospheric aerosol loading, and chemical pollution, there is not as yet sufficient data to draw reasonable conclusions.
At their simplest level these tipping points or boundaries can describe a declining number of fish in the ocean or an increase in average temperatures in the Arctic and Antarctica resulting in the melting of ice. Gradually rising temperatures will lead to the melting of the permafrost in northern places. This process in turn will release even more harmful methane gases stored in the permafrost which then increases the greenhouse gas effect in the atmosphere. This results in even more releases over which humans have no control, and so it goes with each change driving another.
Likewise cod stocks in the Atlantic Ocean reached a point of virtual no return from which the fish were unable to replace their lost members and an entire industry, and to some extent a culture of Newfoundland outports, dependent on those fish, disappeared almost overnight.