On Monday the IPCC released its latest report, the second in a series of three working group assessments undertaken every seven to eight years. The first report on the understanding of the physical science, delivered last year, made clear that human influence on the climate system is already here and affecting many aspects of the climate, and how changes will continue to accumulate unless and until we reach net zero emissions of carbon dioxide and other heat trapping gases.
The new report is concerned with an assessment of the impacts of those changes on human and natural systems and the potential for adaptation to cope with them. The final report, to be published in early April, will assess progress towards reducing greenhouse gas emissions. Taken together with the three special reports and the forthcoming synthesis report, these assessments will inform climate policy decisions over coming years across the world.
This new report makes for truly stark reading. The main message pulls no punches: “The cumulative scientific evidence is unequivocal: climate change is a threat to human wellbeing and the health of the planet. Any further delay in concerted global action will miss a brief and rapidly closing window to secure a liveable future.”
Which raises the question, how will future historians reflect upon our choices as the generation with full knowledge of the impacts of a changing climate that we have begun to unleash? Will we continue to prevaricate or will we grasp the nettle and undertake the meaningful action required to stop further harm and reduce the impacts on humans and nature?
The first critical point the report makes is that climate change impacts are not some future problem that we can ignore for now. Events such as the Pacific North West heat wave of last summer or, closer to our shores, the major flooding in Germany and Benelux have our proverbial fingerprints all over them. Ireland is not immune: the river Shannon flooding associated with Storm Desmond, the Donegal flash floods and the heatwave and drought of 2018 all point to impacts already being felt. These events have a human as well as an economic cost.
The next key takeaway is that climate change is compounding other challenges. Human-caused habitat destruction, biodiversity loss, growing urbanisation, inequity and marginalisation are combining with human-induced climate change to increase the threats to ecosystems and people, now and in the future. Degradation and destruction of ecosystems are reducing our capacity to adapt to climate change. Iconic ecosystems such as coral reefs and low-lying coastal wetlands are critically threatened.
Because we cannot reach net-zero emissions of heat-trapping gases overnight, further warming and hence an exacerbation of these hazards is inevitable over at least the next 20-30 years. How these changes will impact nature and humans depends, critically, upon our ability to adapt. The impacts and risks of climate change are becoming increasingly complex and more difficult to manage, and every additional increment of warming matters. Many of the impacts increase rapidly with additional warming. For example, the report finds that extinction in biodiversity hotspots would increase 10-fold were warming to rise from 1.5 degrees to 3 degrees.
A key point made in the report is that shooting past and then returning to any given warming level such as the 1.5 degrees ambition in the Paris Agreement has a large number of additional impacts compared to stabilising the climate at that warming level without such “overshoot”. We should beware of siren calls of unproven techno-fixes that may be deployable in the distant future.
Adaptation action
Globally, although there has been progress in undertaking adaptation action, progress is uneven and we are not adapting fast enough to our changing climate. The gap between required actions and action undertaken is growing and is leading to increased vulnerability. There are actions that are feasible and effective that can be taken to reduce risks to people and nature, but their effectiveness decreases with additional warming. The more the climate system warms the more options get closed off and the more we will lose key ecosystems and have to, for example, undertake managed retreat from coastlines.
Adaptation action is not just about hard engineering solutions such as sea walls and spillways. Nature-based solutions offer significant untapped potential, not only to reduce climate risks, and deal with the causes of climate change, but also to improve peoples’ lives and livelihoods. Restoring coastal wetlands can offer a buffer to storm surges. Rewetting peat bogs can act to store excess rainfall and release water in times of drought. Reforestation in uplands can reduce river flows downstream.
The report makes clear that to avoid mounting losses we must adapt while simultaneously aggressively addressing our global emissions of heat-trapping gases. Actions to achieve climate resilient and sustainable development are more important than ever. Such development requires ambitious reductions in heat-trapping gas emissions while taking adaptation measures in a manner that improves peoples’ wellbeing. A healthy planet is fundamental to climate resilient development.
International cooperation
The report’s summary for policymakers closes with a warning that we are fundamentally off track for achieving such a climate resilient, sustainable world. But it is not – yet – too late. The choices we make in the next decade will shape not just our future but the future for generations to come. The collective actions we decide to undertake in both emissions reductions and adaptation actions will shape in a fundamental way our futures and those of our children and grandchildren. It requires international cooperation and mobilisation of financial assistance at scale. Events of the past few years have proven that such fundamental change is possible. We have no choice. We must act.
For Ireland to be truly climate resilient requires us to recognise that we are already living in a changed climate with changed risks, and that this will get worse unless and until we reach net zero emissions of heat-trapping gases globally. Even then we have set in train slow changes that will continue to raise sea levels for millennia. It is not sufficient just to try to reduce our emissions of heat-trapping gases, although this is clearly critical.
If we are to avoid as many impacts as possible, it is imperative that governance at all levels starts taking adaptation action as seriously as emissions reductions. If we do not take effective adaptation actions it will exacerbate and compound other challenges around health, housing, education and an aging population. As is the case globally, also nationally those least responsible – the poorest and most vulnerable – will bear the greatest burden unless we act to help them. The time is well past due to mainstream climate adaptation in our national policy decisions.