New Warning: Earth, a "Multi-Disease Patient"
Humans affect the earth’s climate and ecosystems to such an extent that we now risk the stability of the entire planet. That is the message of a new report.
The researchers compare the planet to a multi-disease patient, whose various diagnoses affect each other.
The report, which a large group of scientists from several countries has written, can be compared to the IPCC’s climate report, but considers all the systems that shape the planet. It is about everything from biodiversity and water availability to air pollution, deforestation, and coral death.
We don’t know how long we can continue to cross these limits before the combined pressure leads to irreversible changes and damage, says Johan Rockström, head of the Potsdam Institute for Climate Research in Germany and professor at Stockholm University.
A single system
Human activity affects the Earth’s climate and ecosystems. So much so that we are now risking the stability of the entire planet. And it’s all connected – global warming, species extinction, ocean acidification and chemical emissions.
Through advanced modeling systems, researchers can show how changes in one area affect the others. In addition, actual figures have been presented for the first time on when the so-called planetary boundaries within the nine areas are crossed.
The message is quite depressing. For decades, scientists have shown how much human activity affects the planet. But since 2009, most things have gotten worse, says Sarah Cornell, co-author, and researcher at Stockholm University.
Six out of nine borders have already been crossed. One of the most critical is biodiversity because that area has such extensive effects on several others.
Biodiversity is a good indicator of all living systems in the same way that climate is for physical systems. But to get the two in order, we need to involve other parts and make sure that our waters are not overloaded with nitrogen and phosphorus, for example. Everything is connected, says Johan Rockström.
The sea has buffered
An example of the planet being damaged is that the forest has absorbed 25 percent of all the carbon dioxide emitted by humans and the water has absorbed another 25. But there are many indications that the measure has been reached and that the buffer system will run out. Another example is that the oceans, which absorb a large part of the heat, now release heat instead.
When we talk about the goal of not exceeding 1.5 degrees in global warming, it is assumed that the planet will continue to absorb carbon dioxide, but it is very optimistic to believe that, says Johan Rockström.
The planet’s resistance to human impact is about to run out. Ingo Fetzer, researcher at the Stockholm Resilience Center and co-author of the report, likens the planet to an airplane that previously went on autopilot.
Now we must steer the plane ourselves instead of believing that it will just work itself out. The problem is that we don’t know what all the levers and buttons do, he says.
A positive example exists – the ozone layer. The limit for how much it could decrease was already passed in the 1990s, but as a result of global measures it has been able to recover. In addition to ozone, we are also still on the safe side of ocean acidification and the amount of airborne particles from various emissions.
Here are the planetary boundaries:
- Climate change.
- Loss of biodiversity.
- Chemical pollution.
- Changed land use.
- Fresh water changes.
- Fertilization with nitrogen and phosphorus.
- Depletion of the ozone layer (not passed).
- Ocean acidification (not passed).
- Increased concentration of aerosol in the atmosphere (not passed).
Source: Science Advances