Many of us have heard reports that the health
of our planet may be in danger.
We see images and articles in the media that
report that certain aspects of our planet’s
health have reached dangerous tipping points.
What are these tipping points, and how do
we understand what the international scientific
consensus is about what they mean for the
health of our planet?
The planetary boundaries framework, designed
by scientists at the Stockholm Resilience
Centre, provides a peer-reviewed measure of
planetary health that we can use to determine
the health of the systems on earth.
The research on this framework has been published
in the two leading scientific journals.
At the King’s University in Edmonton, the
King’s centre for Visualization in Science
has designed an online learning tool that
lets you explore the planetary boundaries
framework.
You can learn about the framework, and examine
each of the earth systems included..
We’d like you to focus on how fundamental
knowledge of chemistry can help you understand
the delicate balance required for planetary
health, and the tipping points that could
bring about more serious challenges.
The planetary boundaries framework considers
nine earth systems:
Climate Change
Novel Entities
Stratospheric Ozone Depletion
Atmospheric Aerosol Loading
Ocean Acidification
Biogeochemical Flows
Freshwater Use
Land Use
And Biosphere Integrity
The Global Climate change and Biosphere Integrity
systems are considered “core system processes”,
which means that they are the core indicators
of planetary health, and that they are deeply
connected to the other systems
Each earth system has one or more “control
variables”, which are the way we measure
the overall health of that system.
For example, one of the control variables
for global climate change is the concentration
of carbon dioxide in the atmosphere, and the
control variable for land use is the remaining
forest cover.
These variables work as a proxy measurement
for the health of that earth system, while
the responding variable is the overall health
of that earth system.
The atmospheric aerosol loading and novel
entities systems, as well as the functional
diversity part of biosphere integrity are
still being researched, and control variables
have not yet been finalized or quantified
for these systems
Each control variable has a planetary boundary,
which defines the safe zone for that earth
system.
This is indicated by the green circle.
As the control variable goes beyond the planetary
boundary, it first enters the orange zone,
where there is probably high risk of irreversible
damage to the earth system.
If it goes farther, it enters the red zone,
where we know that there is definitely high
risk to the earth system and the planet.
Right now, at least one of the control variables
in each of the climate change, biosphere integrity,
and biogeochemical flows earth systems are
in the red zone of definite high risk, and
the control variable for the land use earth
system is in the orange zone , indicates that
this system is probably at high risk.
The graphic indicates the current values of
the control variables, and the graphs on each
information panel, or the slider on the main
screen can show you the value of the control
variable since the year 1900.
Just because we have exceeded the planetary
boundary for these earth systems does not
mean that there is no hope.
In the 1970s, certain chemical refrigerants
released into the atmosphere started to deplete
the ozone layer, making risk to that system
more likely However, humanity was able to
stop the use of these chemicals and allowed
the “ozone hole” to slowly repair itself.
We talk about the molecular or material basis
of sustainability to show that understanding
the flow of materials and substances through
society and the environment is crucial to
a sustainable future on our planet.
Most of the control variables for the nine
earth systems are directly related to chemical
processes and the measurement of chemical
substances.
For example, the control variable for climate
change is the concentration of carbon dioxide
in the atmosphere.
This is currently at about 410 parts per million,
or 410 out of every million molecules of air
are carbon dioxide molecules.
The reason that carbon dioxide concentration
is used to measure global climate change is
deeply connected to chemistry.
In the atmosphere, carbon dioxide vibrates
when it absorbs infrared radiation, and through
processes we will study, heats up the atmosphere.
The climate change earth system is also connected
to the other earth systems.
The nitrogen cycle, which includes the transformation
of unusable forms of nitrogen into forms that
can be used in biological processes, also
releases nitrous oxide N2O, into the atmosphere,
which are another potent greenhouse gas.
You can see that all these earth systems are
connected to each other.
The nitrogen cycle is a part of the biogeochemical
flows system, but also can contribute to global
climate change.
Aerosols in the atmosphere are their own earth
system, but also contribute to climate change.
The applet indicated this by highlighting
the connected systems when one system is selected.
The planetary boundaries framework is an important
and useful tool in understanding the processes
that contribute to overall planetary health.
By understanding these systems and the chemistry
behind them, we can equip ourselves with the
tools we need to start to solve the problems
and bring the planet back towards balance.
