The Monthly - Joëlle Gergis
New climate modelling suggests planetary crisis is coming much sooner than previously thought
Dr Joëlle Gergis is an award-winning climate scientist and writer from the Australian National University.
She is an internationally recognised expert in Australian and Southern Hemisphere climate variability and change based in the Australian Research Council (ARC) Centre of Excellence for Climate Extremes.
Her research focuses on providing a long-term historical context for assessing recently observed climate variability and extremes.
In August 2018 she was appointed to the Climate Council, Australia's leading independent body providing expert advice to the Australian public on climate change and policy.
Her book, Sunburnt Country: The future and history of climate change in Australia, is now available through Melbourne University Publishing. |
It’s 3am and I’m awake – again. It’s no exaggeration to say that my
work as a climate scientist now routinely keeps me up at night.
I keep having dreams of being inundated. Huge, monstrous waves
bearing down on me in slow motion. Sometimes I stop resisting and allow
myself to be sucked in. Other times, I watch as a colossal tsunami
builds offshore. I panic, immediately sensing that I don’t stand a
chance. I watch the horizon disappear, before turning to bolt to higher
ground. Around me, people are calmly going about their business.
High water is menacing my subconscious, trying to help me grapple
with the overwhelm I feel in my waking life. My teeth ache from the
nocturnal grinding that my dentist now just acknowledges with a sigh.
As one of the dozen or so Australian lead authors involved in writing
the physical science basis of the “Sixth Assessment Report” of the
United Nations’ Intergovernmental Panel on Climate Change (IPCC), it’s
no wonder I’m on edge. Before the coronavirus pandemic swept the world,
the scientific community was reeling from the most catastrophic bushfire
season in Australian history.
We all watched on in horror as the fires savaged our country,
releasing more carbon dioxide in a single bushfire season than the
country emits in an entire year.
An arc of destruction tore through our
native forests; from the subtropical rainforests of Queensland, through
the temperate forests of southern New South Wales and eastern Victoria,
all the way across to the coastal bushland of South Australia.
A terrifying amount of Australia’s World Heritage areas were burnt –
at least 80 per cent of the Blue Mountains protected area and 53 per
cent of the ancient Gondwana rainforests network.
These are the “last of
the last” of such precious places. Areas that have clung on since the
age of dinosaurs, forced to contend with the processes of evolution
playing out in fast forward. Instead of adapting gradually over
thousands or millions of years, ecosystems were radically transformed in
the space of a single summer, not even a nanosecond in geologic time.
The urgent national conversation we needed to have about climate
change following this collective trauma never happened; instead, we were
all forced to retreat into our boltholes as a deadly plague took hold.
We abandoned the global common, and life shrunk to an intensely personal
scale.
And there we have remained, in suspended animation, waiting for the
health crisis to pass, for some air of normality to return to our lives.
Through it all, scientists across the world have been working around
the clock to progress the IPCC’s monumental assessment of the global
climate – a cycle that typically takes around six years to complete.
As part of this effort, a group of Australian scientists published an
analysis of the latest generation of climate models, assessing what
they are telling us about Australia’s future. After years of
refinements, the new models now contain significant improvements in the
simulation of complex physical processes associated with clouds and
convection, essentially the transfer of heat through the fluid motion of
the atmosphere and ocean. These updates have influenced estimates of
what is termed “climate sensitivity”, a measure of the relationship
between changes in carbon dioxide in the atmosphere and the
corresponding level of warming.
The results have provided an alarming revision of the temperature
increases we thought possible. It is something IPCC scientists are
grappling to understand and communicate, as it has dire implications for
the feasibility of achieving the Paris Agreement targets for reducing
global emissions.
The current goal is to keep global warming to well within 2°C above
pre-industrial levels, and as close to 1.5°C as possible. This is to
avoid instabilities in the planetary processes that have kept our
climate steady for close to 12,000 years. That is, for all of modern
human civilisation.
According to this new study, led by scientists at the CSIRO and
Bureau of Meteorology, the worst-case scenario could see Australia warm
up to 7°C above pre-industrial levels by the end of the century. On
average, the results from 20 models show a warming of 4.5°C, with a
range of between 2.7°C and 6.2°C.
As two of the study’s authors, Michael Grose and Julie Arblaster, noted in
The Conversation,
“the new values are a worrying possibility that no one wants, but one
we must still grapple with”. They quoted the researchers of another
recent climate study, who said, “what scares us is not that the models’
[equilibrium climate sensitivity] is wrong … but that it might be
right”.
Another profoundly significant result is buried 16 pages deep into
the paper. The scientists show that this revision now means that 2°C of
global warming is likely to be reached sometime around 2040 based on our
current high-emissions trajectory. The implications of this are
unimaginable – we may witness planetary collapse far sooner than we once
thought.
I was so disturbed by the new model results that I found it
impossible to get back to my work. How can we not understand that life
as we know it is unravelling before our eyes? That we have unleashed
intergenerational warming that will be with us for millennia? If this
really is the end of days, how can a climate scientist like me make best
use of the time I have left?
In recent years, I’ve looked to brave colleagues who are becoming
increasingly vocal about the climate emergency. One of the scientists I
admire most is Professor Terry Hughes, one of the world’s leading
experts on coral reefs, and our foremost authority on the Great Barrier
Reef.
In late March, just before the national lockdown took effect, Terry
and his colleagues rushed to conduct an aerial survey of the third
mass-bleaching event to strike the reef since 2016. It is the first time
that severe bleaching impacted upon virtually the entire range of the
Great Barrier Reef, including large parts of the southern reef spared
during the 2016 and 2017 events. It’s hard to hide from the reality that
the entire system is in an advanced state of ecological collapse.
In desperation, Terry took to Twitter, sharing his experience of
surveying the carnage: “It’s been a shitty, exhausting day on the
#GreatBarrierReef. I feel like an art lover wandering through the
Louvre… as it burns to the ground.” By the end of his fieldwork he was a
broken man: “I’m not sure I have the fortitude to do this again.”
The honesty of his despair allowed my own to crystallise into a
visceral sense of dread that is deepening by the day. We have arrived at
a point in human history I think of as “the great unravelling”.
Recently, I shared a statistic with my climatology students as I
explained the latest mass-bleaching event: 99 per cent of the world’s
tropical coral reefs will disappear with 2°C of global warming. This
future no longer feels impossibly far away, it’s happening before our
eyes.
Looking around the room, I couldn’t help but feel sorry for them.
They have inherited a planetary mess, yet are more distracted and
disconnected from each other, themselves and the natural world than any
generation that has ever lived.
As each season passes, it’s painfully clear that we are witnessing
the destabilisation of the Earth’s climate. There are things we can
still save, but it’s now too late for some areas such as the Great
Barrier Reef and tracts of ancient rainforests.
In Australia we wear our badge of resilience with a hefty dose of
national pride. But scientists on the frontline of the climate crisis
understand that some things in life, once gone, can never be replaced.
If the new models turn out to be right, there is no way we can adapt to
the catastrophic level of warming projected for a country like
Australia.
Even placing the new models aside, the 2019 UN Environment
Programme’s “Emissions Gap Report” shows that a continuation of current
global emission reduction policies could see the Earth’s average
temperature rise a staggering 3.4 to 3.9°C by 2100.
If we continue along our current path, by any measure, we will sail past the Paris Agreement targets in a handful of decades.
Some of our most precious ecosystems will never recover, including
some of what was destroyed in Australia during our Black Summer. Gutted
landscapes will struggle on, trying to regain some semblance of an
equilibrium. But the truth is the destruction we have unleashed will
reverberate throughout the ages.
We are witnessing the unthinkable. Facing the unimaginable.
Psychologically, many people already sense it’s the beginning of the
end. But is this the end of the era of fossil fuels, or life as we know
it? As the planetary crisis accelerates, we must confront the reality
that what we do now will forever alter the course of humanity and all
life on Earth.
My dreams are warning me that a metaphorical tsunami is approaching,
threatening to destroy all that we hold dear. We must wake up and rush
to higher ground before it’s too late.
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