Madrid (EFE).- Science has established for the first time what are the limits of security and justice that should not exceed the main indicators of environmental deterioration; and has concluded that some of those red lines have already been crossed and many of the impacts on human well-being are now unavoidable.
Thus, scientists have set at 1.5 degrees the “safe” limit above which the Earth’s average temperature should not rise to avoid a high probability of multiple climatic inflection points; that has not yet been breached. But it sets the limit considered “fair” at 1 degree to avoid high exposure to significant damage caused by climate change; this one has already been breached.
Convened by the international organization “Future Earth”, fifty researchers belonging to the “Earth Commission” -an international platform of scientists who collaborate for a more sustainable world- publish today in the journal Nature the conclusions of their work and have pointed out what are those thresholds that should not be crossed to safeguard a planet that can support human well-being.
The limits that scientists describe as “safe” are those that guarantee stable and resilient conditions on Earth; the “fair” are those that minimize human exposure to the most significant harms (such as loss of life, forced displacement, loss of food or resources such as water, nutritional security or chronic diseases).
Safe and fair limits for environmental deterioration beyond climate
In addition to climate, researchers have set those “safe” and “fair” limits also in terms of biodiversity, fresh water, and different types of air, soil, or water pollution, and have concluded that in most cases have been exceeded and that humans are taking “colossal” risks and putting the stability and resilience of the planet at risk.
They maintain, for example, that between 50 and 60 percent of global nature should remain intact (unfulfilled, both in terms of security and justice); that the percentage of alteration of the flow of surface water should not exceed 20 percent (non-compliance); or that the use of groundwater should not be greater than the recharge capacity of the aquifers (also breached, both in terms of security and justice).
Human action and its consequences
Researchers have also warned that fertilizer cycles such as nitrogen or phosphorus also exceed the limits that are considered safe and fair, and that many human activities are altering natural water flows and releasing excessive amounts of nutrients into rivers, which it poses serious threats to ecosystems and to the vital contributions they make to the well-being of people.
Among the fifty researchers from around the world who have participated in the work is the researcher Noelia Zafra, from the Basque Center for Climate Change (BC3), who has underlined the relevance of this research, since scientific studies of the biophysical limits have been carried out of the Earth since the seventies of the 20th century but for the first time the calculations have been carried out including “intra and intergenerational social justice and with all living beings on Earth”.
In statements to EFE, Zafra has been exhaustive in asserting that many of these limits have already been exceeded and that some of the consequences of this are going to be irreversible, but also that “the most important thing now is to know that it is necessary to work, and a lot, so that the consequences of exceeding those limits are as little negative as possible”.
And it is committed, in addition to strict compliance with the Paris Agreement to counteract the climate and biodiversity crisis, to promote new social agreements “much broader and at all scales -from global to local- in order to implement all the necessary measures in a fair way.”
Systems that determine the habitability of the Earth
The work presents for the first time quantifiable numbers and a solid scientific basis to assess the health of the planet not only in terms of stability and resilience, but also in terms of human well-being and equity and justice, Swedish researcher Johan Rockström has highlighted in the publication. , co-chair of the Earth Commission, lead author and director of the Climate Impact Research Institute in Potsdam, Germany.
“We cannot have a biophysically safe planet without justice; this includes setting fair goals to prevent significant harm and guarantee access to resources for people and just transformations to achieve those goals”, confirmed Joyeeta Gupta, co-chair of the Land Commission and professor at the University of Amsterdam.
The researchers’ work concludes that the Earth system is in danger and that the global objectives have focused on climate change and limiting global warming, but stresses that all the scientific evidence clearly shows that it is necessary to manage all the other systems and biophysical processes that determine the habitability of the planet.
A safe and just transformation to a manageable planet requires urgent collective action by multiple actors, especially governments and businesses, to act within the limits of the Earth system to keep the planet’s life support intact, the researchers have concluded, and They have warned that the administration of the global commons “has never been more urgent or important”.