I believe that the idea of planetary boundaries, while useful as a model to try to predict various environmental risks, is also vulnerable to being exploited by the authors and by the media in order to promote catastrophist narratives of environmental issues. In a way, it reminds me of the rather ridiculous Doomsday Clock kept by the Bulletin of the Atomic Scientists. It is perhaps a remnant of the environmental idea of carrying capacity, which usually refers to the ability of available resources to support a population. The idea failed to correctly predict the impacts of available resources amid a rising population. I have written about the planetary boundaries idea being vulnerable to promoting catastrophist narratives in 2023 with my post: The Planetary Boundaries Framework: How Useful is the Concept and Does it Support Catastrophism? I had also read and reviewed its director, Johan Rockstrom’s 2016 book, Big World, Small Planet.
Apparently, the Potsdam
Institute of Climate Impact Research is a very influential organization. They
put out the second-most-cited climate paper in 2024. Unfortunately, the data
conclusions were compromised by a very significant, though perhaps
counterintuitive error. I wrote about that only a week ago in my post: A Paper Published in Nature That Predicted Huge Drops in GDP
Due to Climate Change Shown to Be Inaccurate When the Data Was Examined: The
Paper was Widely Cited and Widely Adopted in Climate Risk Modeling.
The institute did not offer a real retraction but changed their modeling to fit
the new data and a similar conclusion when they should have seen that their
original conclusion was no longer supportable, which was strongly criticized as
an inadequate response. Climate financing institutions updated their risk
models to reflect the original conclusions, but apparently have yet to update
them to reflect the inaccurate data. This further flags the institute as
biased. Again, while I think the idea is useful and that we should attempt to
evaluate and track these risks, it should be done strictly according to science
and without bias.
The latest paper in One
Earth, Breaching planetary boundaries: Over half of global land area
suffers critical losses in functional biosphere integrity, attempts to
model this parameter and present the deliverables in global maps of the level
of risk. The paper is a collaboration between the Potsdam Institute for Climate
Impact Research in Germany and the BOKU University in Vienna, Austria. They use
the concept of functional biosphere integrity to refer to “the plant world's
ability to maintain the essential cycles of carbon, water and nitrogen that
regulate the Earth system,” according to Newsweek. They are attempting to
determine a boundary or line between what is safe and what is high-risk, which,
if crossed, means that those systems are in danger. One problem with this is
that determining such a line is difficult. It necessarily involves modeling
complex systems with many variables and carries all the uncertainties of
modeling. They consider functional biosphere integrity to be a core element of
the Planetary Boundaries framework, like biodiversity loss and climate change.
Paper author Fabian Stenzel explained in a statement:
"It is therefore becoming even more important to
quantify the strain we're already putting on the biosphere...to identify
overloads. Our research is paving the way for this."
The authors find that:
“…the integrity of ecosystems has already been
critically compromised across large parts of the planet.”
The summary of the paper,
given below, shows how they derived their estimates, noting that it is only a
first step. I am a bit skeptical that such determinations can be accurately
made on a global scale with modeling that relies on assumptions. I would argue
that different regional ecosystems have different levels of resilience to
changes and that measuring things like risk factors is not easy, as assumptions
must be made for a qualitative metric like biosystem integrity that may not
hold up.
Summary
“Mapping ecosystem integrity is a key task of the
planetary-boundaries framework. Two new control variables have been suggested
for the core planetary boundary for functional biosphere integrity: (1) human
appropriation of net primary production (HANPP) and (2) a metric for ecological
disruption (EcoRisk). However they have not yet been mapped spatially and
temporally explicitly. Here, we use simulations with the dynamic global
vegetation model LPJmL to map the status of these variables at a spatial resolution
of 0.5° × 0.5° for every year since 1600. We additionally quantify local
degradation thresholds by comparison with independent biosphere integrity
indicators. We finally aggregate results globally to a planetary boundary
status as the land area transgressing the local thresholds. We find that the
local boundary is currently transgressed on 60% of the global land area, with
38% already at high risk of degradation. This study provides an important first
step and opens the opportunity for further research, especially for finding a
planetary-scale threshold.”
One thing that can be noted from the maps below is that, in general, where there are more humans, there is more functional biosystem integrity loss.
References:
60% of
Earth's land at risk, map shows. Maria Morava, Newsweek. August 15, 2025. 60%
of Earth's land at risk, map shows
Breaching
planetary boundaries: Over half of global land area suffers critical losses in
functional biosphere integrity. Fabian Stenzel, Liad Ben Uri, Johanna Braun, Jannes
Breier, Karlheinz Erb, Dieter Gerten, Helmut Haberl, Sarah Matej, Ron Milo, Sebastian
Ostberg, Johan Rockström, Nicolas Roux, Sibyll Schaphoff, and Wolfgang Lucht. One
Earth. Volume 8, Issue 8. 101393. August 15, 2025. Breaching
planetary boundaries: Over half of global land area suffers critical losses in
functional biosphere integrity: One Earth
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