The IPCC report is clear: nothing short of
transforming society will avert catastrophe
Patrick
Vallance
Achieving net zero will require action from everyone –
and a renewed emphasis on science and innovation
Patrick
Vallance is the UK government chief scientific adviser
Mon 9 Aug
2021 12.43 BST
The release
today of the first part of the Intergovernmental Panel on Climate Change’s
sixth assessment report makes for stark reading. It reaffirms that
anthropogenic climate change is real, present and lasting: it is now
unequivocal that human influence has warmed the atmosphere, ocean and land to
an unprecedented degree, with effects almost certain to worsen through the
coming decades.
The report
also dispels any notion that the effects of the climate crisis are abstract or
distant. Extreme events are being felt across the world, from wildfires in
Australia, Sweden and north-west America to heatwaves in Siberia and Canada and
the devastating drought in South Africa. Evidence has grown since the last
assessment report that human activity has exacerbated extreme weather events.
Without urgent action, such events will continue to get worse. Moreover, sea
levels are projected to rise over this century. Rises of as much as 2m cannot
be ruled out, leaving low-lying lands and coastal communities extremely
vulnerable.
One of the
headline figures in the report is that average global temperatures in 2011-2020
were 1.1C higher compared with 1850-1900. Though this may seem like a small
increase on any individual day, the increments matter in the long term. With
every additional fraction of a degree increase in global warming, changes in
extreme events such as heatwaves, floods and droughts become larger.
The Paris
agreement in 2015 was momentous in committing signatories to limiting global
warming to 2C above pre-industrialised levels, and preferably 1.5C. The IPCC’s
report makes plain that our goal should be to keep temperature rises as small
as possible. Relative to a 2C increase, limiting temperature rises to 1.5C
would reduce the risks of food and water shortages, improve prospects for
endangered species and protect human health from air pollution, malnutrition
and extreme heat. We must aim for that goal.
Limiting
global warming to 1.5C is ambitious – but is not fanciful. In the 2019
amendment to the Climate Change Act, the UK showed the intent required and
committed to reaching net-zero emissions by 2050. Still, achieving that aim
will be a challenge. The climate crisis is as much a rural problem as an urban
one. It is both economic and human, domestic and international. This means
transformation is required at every level of society: individuals, employers,
institutions and international partners will need to work together to
understand the trade-offs, agree compromises and seize opportunities. And just
as scientists are pooling insights from diverse fields of expertise,
policymakers will need to work in new ways, sharing ideas across disciplines to
plot a clear path from here to net zero. This is a whole systems challenge.
Tackling it will require a systemic approach.
Working
back from 2050, it is clear that reaching net zero requires a renewed emphasis
on science and innovation. First, we need to assess the technologies already
available, identify those we need at scale by the middle of the century and
deploy them as fast as possible. Second, we need to rigorously monitor progress
against intermediate targets to make sure we are on track. Third, we need to
identify areas where practical answers don’t yet exist – where research and
innovation is still required to answer specific challenges – and invest
accordingly; done well, these investments can seed the industries of the
future. Across all this, we need to think globally, ensuring climate
innovations are affordable and that their benefits are shared equally.
We must
also recognise that the climate has already changed, and will continue to do so
as we near 1.5C. The seas are rising, and floods and wildfires are more frequent.
Again, science and engineering can help us to adapt, boosting the resilience of
the most vulnerable and strengthening global food security. Existing tools can
anticipate adverse events, while adjusting the design of cities, transport
systems and agriculture can minimise their worst effects.
Together
with the Cop president designate, Alok Sharma, we will ensure that the
forthcoming climate change conference (Cop26) will emphasise science and
innovation, including a dedicated day of activity. We hope that one of the
legacies of Cop26 will be that science is considered as important in producing
solutions to climate change as it is in understanding it.
Each of the
IPCC’s assessment reports are an extraordinary undertaking, drawing on
thousands of experts from around the world to provide the most comprehensive
assessment of the present and future climate to date. They have made their
mark, too. The second assessment report, published in 1995, memorably stated
that “the balance of evidence suggests a discernible human influence on global
climate” and ultimately led to the Kyoto protocol committing parties to
limiting greenhouse gas emissions. The fifth informed the Paris agreement of
2015. We hope that the sixth will spur similarly historic action in Glasgow in
November and set the world on a safe and sustainable trajectory.
Patrick
Vallance is the UK government chief scientific adviser
The
following scientific advisers also contributed to this piece: Stephen Belcher,
chief scientific adviser, Met Office; Gideon Henderson, chief scientific
adviser, Defra; Paul Monks, chiefscientific adviser, BEIS; Mike Short, chief
scientific adviser, DIT; and Charlotte Watts, chief scientific adviser, FCDO
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