Lumen Winter 2023 - Flipbook - Page 10
Environment report card
– failing our planet
Professor Andy Lowe, Interim Director,
Environment Institute, gives his sobering
overview of the state of the planet.
With the recent waves of climate extremes
and disasters – floods, drought and fires – it
is clear that we are now living beyond the
boundaries of many of Earth’s life support
systems, and we are impacting the health
and wellbeing of people and our planet.
But this isn’t the first time we’ve faced
serious environmental issues.
During the height of industrial revolution in
Europe, mills pumped out coal dust causing
pollution and smog on a massive scale,
shortening the lives of workers and broader
communities.
More recently, aerial nitrous and sulphurous
pollution from power stations and carbofluoro compounds from industrial processes
have produced acid rain and ozone hole
depletion, driving forest loss and elevated
cancer rates.
But the challenges of today are on a truly
global and multinational scale. So, let’s suck
the lemon and take a cold hard look at the
key issues we are facing and what we can
potentially do about them.
Climate change
Perhaps the largest challenge of our
generation. The uncontrolled release of
greenhouse gases is leading to runaway
climate change that is driving increased
climatic extremes such as droughts, floods,
ocean inundation and bushfires.
While international agreements to
decarbonise energy, transport, industry and
agricultural processes are being developed
for 2050, we will need to reach many of
these targets by 2030 to stay within a safe
temperature rise of 1.5oC, but this target is
looking increasingly challenging.
Ocean acidification
Around a quarter of the CO2 we emit goes
into the ocean. Here it forms carbonic acid,
acidifying the surface water, locking up
carbonate and making it difficult for shell
forming marine life (coral and shellfish) to
grow. Losses of these marine ecosystems
through ocean acidification could potentially
lead to drastic reductions in fish stocks.
Reining in greenhouse gas emissions
will stop both climate change and ocean
acidification.
The challenge ahead
Biodiversity loss and extinctions
A number of intergovernmental
organisations have documented, in detail,
the problems we are facing, including
the Intergovernmental Panel on Climate
Change, Millennium Ecosystem Assessment,
and Intergovernmental Platform for
Biodiversity and Ecosystem Services. But
the scale of these issues has perhaps been
best captured by the planetary boundaries
concept developed by the Stockholm
Resilience Centre.
Changes to natural ecosystems from human
activities have been more rapid in the past
50 years than at any other time in human
history. The main drivers of change are
our demand for food, water, and natural
resources.
In a simple graphical way, major
environmental challenges have been
examined and then considered as to whether
we are within Earth’s coping mechanisms
(i.e. within planetary boundaries) or are
currently operating outside our planetary
coping boundary. The assessment, first
undertaken in 2009 by Johan Rockström
who led a group of 28 internationally
renowned scientists, has been updated
a number of times to examine key
environmental threats, including:
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THE UNIVERSITY OF ADELAIDE
The current high rates of species extinction
(the most rapid in the history of life on
Earth) can be slowed by efforts to protect
the biosphere, enhance habitat extent and
quality, and improve connectivity between
ecosystems.
Land system change
Forests, grasslands, wetlands and other
vegetation are being converted into
agricultural and urban land uses all over
the planet. This change is one of the main
driving forces behind biodiversity loss, and
the cycling of water, carbon, nitrogen and
other elements.
Globally, including in Australia, a target of
30% natural landcover is being promoted
to help restore balance between natural and
managed systems.
Freshwater and hydrological cycles
On a monumental and global scale, we
have modified river flows and changed
water vapour dynamics. These shifts in
the hydrological cycles have been abrupt,
and water is becoming increasingly scarce,
leading to water stress and conflict.
A system of consumptive freshwater use,
including allocations for environmental
and cultural flows, is required to maintain
the overall resilience of Earth systems and
to avoid the risk of ‘cascading’ local and
regional thresholds.
Nitrogen and phosphorus flows to the
biosphere and oceans
The biogeochemical cycles of nitrogen and
phosphorus have been radically changed
largely due to the industrial-scale production
and application of agricultural fertiliser.
However, rather than promoting crop
growth, nitrogen and phosphorous released
into our atmosphere pollutes waterways,
coastal zones and terrestrial biospheres,
leading to oxygen starvation and
‘dead zones’.
Reduced and targeted fertiliser applications
are being developed through agtech and
nano science developments.
Chemical pollution and the release of
novel entities
We are still releasing large quantities of
toxic and long-lived substances into our
environment, including plastics, heavy metal
compounds and radioactive materials.
Even when the uptake of these pollutants
is at sub-lethal levels for organisms, they
can reduce fertility and cause permanent
genetic damage. For plastic pollution alone,
eight million tonnes enter our ocean from
rivers each year, and we are all ingesting
microplastics through sea salt, tap water,
and shellfish.
