Johan Rockstrom has redefined sustainable development by applying his theory of the nine planetary boundaries that we must remain within in order for the planet to remain habitable, with our efforts to meet the UN’s SDGs. His research signals that if we are to protect human life and biodiversity, we need to apply radical thinking, far outside of the environmental strategies that are currently in place.
As an internationally recognised scientist, famous for his work on global sustainability issues, Rockstrom helped lead a team of scientists to model and explain the ‘planetary boundaries framework’.
First published in 2009, and then updated in 2015, the Planetary Boundaries framework argues that there are nine factors that are fundamental in maintaining a "safe operating space for humanity" – factors that balance the world’s systems to ensure the Earth remains habitable. Essentially, Rockstrom believes that if we can regulate these nine factors, there is a higher chance of global prosperity and equity. Rockstrom and his team defined these crucial nine boundaries as:
The ozone layer creates a shield around the world, filtering out ultraviolet (UV) radiation from the sun. The discovery of the hole ozone layer over the Antarctic was proof that increased use of certain chemicals interact with polar stratospheric clouds and imbalance the ozone layer to the point that it disappears. Action taken as a result of the Montreal Protocol meant that the situation has since stabilised, but that it must be continually monitored to ensure the balance does not falter once more.
The Millennium Ecosystem Assessment of 2005 concluded that changes to ecosystems due to human activities were more rapid in the past 50 years than at any time in human history, increasing the risks of abrupt and irreversible changes. The report stated that increasing populations placed on food, water and natural resources has meant many geographies have suffered severe biodiversity loss.
It is possible to slow the damage to ecosystems and limit extinction by efforts by improving the connection between agricultural productivity and biodiversity, but more research is needed to define the balance of this relationship. Until then, we need to address the pressure our increasing populations have on the planet.
Emissions of toxic synthetic organic pollutants, heavy metal compounds and radioactive materials have resulted in the biggest changes humans have made to the planet. These compounds affect atmospheric processes, alter climate and can have potentially irreversible effects on the physical environment. Along with dramatic reductions in bird populations and impaired reproduction and development in marine mammals, these chemicals can cause reduced fertility and potentially permanent genetic damage in humans.
As there are so many types of additive compounds, their effects remain poorly understood scientifically. What we do know, is that these chemicals pose significant threat to life and their use and management need far closer attention.
The Earth’s atmosphere has passed 390 ppmv of CO2, meaning it has already passed the planetary boundary that represents stability and is fast approaching thresholds that indicate we are causing irreversibly damaging change as the result of a warming world. For example, the loss of summer polar sea-ice is almost certainly irreversible. The ongoing destruction of the world's rainforests is also a potential tipping point that will change the climate-carbon cycle for good. Efforts must be made to reverse the effects of warming to ensure the Earth is still able to support human life. As Rockstrom warns; “the question is how long we can remain over this boundary before large, irreversible changes become unavoidable.”
A quarter of the CO2 that humanity emits into the atmosphere is ultimately dissolved in the oceans forming carbonic acid and altering the chemistry of the ocean. Compared to pre-industrial times, surface ocean acidity has already increased by 30 percent but beyond a certain concentration, organisms such as corals and some shellfish and plankton species will not be able to survive, changing the composition of our oceanic ecosystems forever.
The ocean acidification boundary has ramifications for the whole planet. It is also an example of how tightly interconnected the nine boundaries are - as the atmospheric CO2 concentration is an underlying controlling variable for both the climate and the ocean acidification boundaries. This boundary requires us to significantly reduce carbon emissions if we are to avoid poisioning the world’s oceans.
The freshwater cycle is strongly affected by climate change. Water is becoming increasingly scarce - by 2050 about half a billion people are likely to be subject to water-stress, increasing the pressure to make man-made changes to our water systems with far-reaching ramifications for the environment. This water-system boundary requires us to balance consumptive freshwater solutions with less evasive changes to global water systems that irreversibly change the landscape.
Around the world, natural forests, grasslands and wetlands have been converted to agricultural land. The aggregated impacts of this land change have consequences for Earth system processes on a global scale and it has been found to be the key force behind the serious reductions in biodiversity. This boundary requires us to reduce human changes to land systems and find a revised approach that considers the quantity of land, its function, quality and distribution in order to balance CO2 levels and support biodiversity.
The biogeochemical cycles of nitrogen and phosphorus used in industrial and agricultural processes are radically changing our ecosystems. For example, man-made chemicals – such as fertilizer - convert more atmospheric nitrogen into reactive forms than all of the Earth's processes combined. The chemicals become reactive nitrogen that is emitted to the atmosphere and then rained out, polluting waterways and coastal zones or accumulating in the biosphere on in our water systems. To balance this boundary, we need to embrace new forms of farming that turn away from the use of harsh chemicals for fertiliser and towards the concept of agroecological farming.
Aerosols have a major impact on the Earth's climate. They affect cloud formation, global and regional weather patterns such as monsoon systems and impact how much solar radiation is reflected or absorbed in the atmosphere.
Humans affect aerosol loading by emitting atmospheric pollution and also by changing land-use, increasing the release of dust and smoke. Crossing the aerosol loading boundary has already resulted in changes to climate regimes that are adversely affecting many living organisms and causing around 800,000 people to die prematurely each year. It is vital that we control the level of aerosols in the atmosphere so as not to worsen the already devastating effects of extreme weather incidents and links to respiratory disease.
Rockstrom argues that although the 2015 Paris Agreement and UN’s Sustainable Development Goals (SDGs) provide a framework and a target to protect our way of life, if we are to ensure that our planet remains a stable operating environment for humanity to survive, we need to go beyond these measures. His indicated that in almost every future scenario modelled, both the planet, and human prosperity suffered. For example, when looking back, the tram found that in the 1980s, we were in a safe operating space but not meeting many of the SDGs but by 2015, we were delivering on an increasing number of SDGs, lifting millions of people out of poverty, but doing it at the expense of the safe operating space on earth.
The team therefore concluded that to ensure we are able to live on this planet and help design a world with better equality levels; “We need to go into a transformative, disruptive future, where we start thinking outside of the box.”
Rockstrom believes that combining the SDGs with the Planetary Boundaries framework provides “an incredible wake-up call but also an opportunity for transformative change, where we shift gears and really start thinking of the SDGs as a transformative agenda within a safe operating space on earth. In other words, we can build a safe and just world. We just have to really, really get on with it.”
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