The 5th planet boundary has been crossed: and then?
On January 18th, scientists from the Stockholm Resilience Center (SRC) announced that we have crossed a 5th planetary boundary: the limit of “chemical pollution” or “introduction of new entities” in the biosphere. This is the 5th planetary boundary out of the 9 identified. It is the world’s ecosystems that are in danger, nothing less.
We owe this concept to Johan Rockström, who led a group of 28 international scientists in 2009 to identify the processes that regulate the stability and resilience of the Earth system. They propose a measure of the planetary boundaries within which humanity can continue to develop and thrive. They identify environmental changes induced by the human footprint that may affect ecosystems and well-being. These are known as the nine limits of the planet.
Which are those 9 boundaries?
The concept of planetary boundaries defines a safe and just development space for humanity, currently based on nine biophysical processes that together regulate the stability of the planet. The article “Planetary Boundaries: Exploring the Safe Operating Space for Humanity” in the journal Ecology and Society in 2009 sets the scene. It defines 9 planetary boundaries and gives for each one an indicator:
Climate change: the concentration of CO2 in the atmosphere must be below 350 ppm.
Ocean acidification: the saturation state of surface sea water is measured.
Stratospheric ozone depletion: ozone concentration is measured.
Nitrogen and phosphorus flows to the biosphere and oceans: first, the fixation of nitrogen by industry and agriculture is measured, then, the discharge of phosphorus into the oceans (it should not exceed more than 10 times the amount of natural discharge).
Freshwater consumption and the global hydrological cycle: it must be less than 4000 km3 per year.
Land system change: less than 15% of the available land area should be cultivated.
Loss of biosphere integrity (biodiversity loss and extinctions): the annual rate of extinctions must be less than 10 extinctions per million species.
Chemical pollution and the release of novel entities
Atmospheric aerosol loading
The last two, chemical pollution and the increase of aerosols in the atmosphere are not quantified. That is, the team of scientists could not find enough measurable indicators or did not have enough information about the “tipping point”. The other 7 are, however, quantifiable and three of them (climate change, biodiversity erosion and the nitrogen cycle) have already been exceeded.
What does crossing the 5th planet boundary mean?
The 5th planetary boundary to be officially exceeded is the one called chemical pollution, the “new entities” created or introduced by Humans. When we talk about chemicals, we are talking about plastics in particular.
There are about 350,000 different types of manufactured chemicals on the market today.
Plastic production increased by 79% between 2000 and 2015. The total mass of plastics on the planet is now more than twice the mass of all living mammals, and about 80% of all plastics produced remain in the environment. Plastics contain more than 10,000 other chemicals, so their environmental degradation creates new combinations of materials – and unprecedented environmental risks. Plastics production is set to increase and forecasts indicate that the release of plastic pollution into the environment will also increase, despite considerable efforts in many countries to reduce waste.
The discovery of a 7th continent and in particular the 36 million km2 of chemical waste trapped in a huge vortex in the North Atlantic had a strong impact on public opinion. However, habits die hard and plastic continues to be manufactured and there is still a massive usage of it.
Circular economy as one of the solutions
The researchers conclude that current increasing trends of chemical production and release put the health of the Earth system at risk. The authors call for actions to reduce the production and release of pollutants.
“We need to be working towards implementing a fixed cap on chemical production and release,” says Carney Almroth.
“And shifting to a circular economy is really important. That means changing materials and products so they can be reused not wasted, designing chemicals and products for recycling, and much better screening of chemicals for their safety and sustainability along their whole impact pathway in the Earth system”, adds Sarah Cornell from the Stockholm Resilience Centre.
Recycling alone will never be enough. It is the production of plastic that must be limited. What do the oil majors think about this, as they benefit from the rise in crude oil prices and publish record results?