Saturday, 13 August 2022 | 15.5°C Dublin

E ven if we hit net zero by 2050, serious harm will be done. That is no excuse for inaction

Melting: An iceberg in Disko Bay, Greenland. The collapsing ice sheet there will add seven metres to the sea level. Photo by Sean Gallup/Getty Images

Cover more of our urban areas with plants: Ashe Conrad-Jones and Amy Van Den Broek from Pocket Forests tend to their installation in Dublin. Photo by Frank McGrath

Growing demand: A farmer tends his crops in Kenya. To lower greenhouse emissions we need to devote more land to growing crops. Photo by Tony Karumba via Getty Images

Invest in zero-carbon public transport: Environment minister Eamon Ryan with a hydrogen-powered bus during a trial in 2020

A house in England has a heat pump installed. Photo by Leon Neal/Getty Images

Bill McGuire is Professor Emeritus of Geophysical and Climate Hazards at University College London and author of ‘Hothouse Earth: An Inhabitant’s Guide’

Too many of us imagine that climate change just means that things will be a touch warmer and that we will somehow muddle through, like we always do. This is plain wrong. Instead of global warming and climate change, we now talk of global heating and climate breakdown, and there is a reason for this. Our planet is not only warmer, but heating more rapidly than at any time in at least the last 55 million years, and quite possibly at the fastest rate in its 4.6 billion-year history.

T his is driving not a changing climate but one that is breaking down. The evidence for this is all around us as global heating trashes our once equable climate and translates into extreme weather far more rapidly than anyone — including climate scientists — would have thought possible. It is especially telling that a hypothetical weather forecast mocked up a few years back by the British Met Office for 2050 was the spitting image of the actual weather map for July 19 this year — the hottest on record for the UK by a country mile — close to 30 years ahead of its time.

Ireland dodged the blistering heat that held much of the UK in its grip for two brutal days last month, but this won’t last. As the global average temperature continues to ramp up — it is now about 1.2C hotter than during pre-industrial times — so heatwaves will become more widespread, longer-lasting and more intense. Nowhere will be immune to excessive heat, nor the wildfires, torrential rains, floods and more powerful storms that a failing climate will bring.

All this makes it so much more vital that greenhouse gas emissions be slashed as quickly as possible. In this regard, Ireland has been a laggard, to say the least. In 2021, it fell to 46th out of 60 nations in the Climate Change Performance Index.

There have been improvements, and annual carbon dioxide emissions per head of population have fallen from more than 12 tonnes in 2001 to less than seven tonnes in 2020. Nonetheless, at more than 61 million tonnes, the country’s greenhouse gas emissions in 2021 were 4.7pc up on the previous year. The Government is at least attempting to remedy this poor performance, and like the UK is targeting net zero carbon emissions by mid-century. It’s 2021 legally binding Climate Action Plan seeks to halve greenhouse gas emissions by 2030 and bring them down to net zero no later than 2050.

Wind Energy Ireland has indicated that the country’s electricity system can be fully decarbonised as early as 2035. Agriculture remains, however, a big problem — especially beef farming. Agricultural practices pump out almost 40pc of the country’s emissions, most of which is related to the national cattle herd and the application of nitrogen-rich fertilisers. Emissions cuts by the agriculture sector of 25pc by 2030 were agreed last week, but according to the Climate Change Advisory Council, these are still too low. The council also questioned the figures for emissions reductions across all sectors which, they say, amount to just 43pc by 2030 — not the 51pc required by law.

There are other issues too. Ireland’s Climate Action Plan addresses only domestic emissions. As such, it does not relate to the country’s carbon footprint, which includes emissions related to everything ‘consumed’ that is made or farmed abroad. In 2019, for example, Ireland ‘imported’ an additional 11pc of carbon dioxide emissions on top of its domestic total. Nor does the plan address aviation or shipping emissions, which add even more to the total.

But there is a much bigger, overarching problem. Net zero emissions in 2050 is simply too late. The global average temperature is already up 1.2C and climbing rapidly. To keep below a 1.5C rise in global average temperature — widely regarded as marking the dangerous climate change guardrail — global emissions will need to fall by 45pc by 2030. This might be possible in theory, but practically, this is just not going to happen. The reality is that emissions are on track to climb by 14pc by this date, a figure that could end up being higher due to energy supply issues associated with the Ukraine war.

Growing demand: A farmer tends his crops in Kenya. To lower greenhouse emissions we need to devote more land to growing crops. Photo by Tony Karumba via Getty Images

In all probability, the 1.5C guardrail will be shattered within the next 10 years, and even the 2C mark will be surpassed if global emissions reach net zero in 2050 — which is still far from guaranteed. Assuming, however, that this is achieved, dangerous all-pervasive climate breakdown will by this stage be well and truly locked-in. The extreme weather that is already plaguing the planet will be far more widespread and more frequent, bringing a hellish mix of heatwave, wildfire, storm and flood.

Already, the ramifications of a failing climate will be pulling at the threads that hold the fabric of global society and economy together. By mid-century, it is predicted that the world will need half as much food again to feed a still-climbing population, but due to excessive heat and extreme weather, crop yields could be down by as much as 30pc. Inevitably, this will bring pervasive food shortages, famine, war and civil strife, and neither Ireland nor the UK should expect to be immune.

Even if the world achieves net zero emissions by 2050, it will be a world we no longer recognise. And it doesn’t stop there. Barring the onset of large-scale feedback effects, such as the wholesale release of methane from Arctic permafrost, the global average temperature should stabilise soon after net zero carbon has been achieved. But temperatures won’t fall, so that whatever global average temperature prevails once emissions hit zero will persist for many decades, perhaps centuries, before slowly falling back. The seas, too, will keep rising for centuries.

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Any tipping points crossed will stay crossed, so an irreversibly collapsing Greenland ice sheet will continue to crumble, eventually adding about seven metres to the global sea-level; sufficient to swamp Dublin and every other coastal city.

In this regard, it is sobering to look back at the last interglacial period 125,000 years ago, a time known as the Eemian. Then, temperatures were comparable to what they are today, but the sea level was between six and nine metres higher.

Going back even further — 15 million years — to the so-called Middle Miocene Climate Optimum (MMCO), provides an even more disturbing picture. Then, atmospheric carbon dioxide levels were comparable to those of today, perhaps even a little lower, but the global temperature was 2C-4C higher, and the sea level elevated by 20m. This, then, paints a bleak picture of where we are quite likely headed.

It is easy to get overwhelmed by the fact that such scenarios are almost certain to come to pass. But we can’t afford to let such feelings feed inertia. The emissions targets set for Ireland by the Government may seem difficult, if not impossible, to achieve. And the same applies in nations the world over. But if the dangerous, society-fraying, climate breakdown that is inevitably coming is not to transmogrify into cataclysmic climate collapse, then we have no choice: not only to hit the targets, but to do even better.

It doesn’t matter either, how large a country is, or how great its emissions. Every one of us is or will be affected by the climate emergency, and those of us in the developed world need to make recompense for the problems we have brought upon our planet. Even a small country like Ireland has pumped out more than two billion tonnes of carbon during its history.

Cancelling out Ireland’s 60 million plus tonnes of greenhouse gas emissions every year — and the world’s annual 40 billion or so tonnes of carbon effluent — is possible, provided the will is there. The problem is that governments are hiding behind the excuse, “We can’t cut emissions faster because…”, when what they should be doing is asking: “How can we reduce emissions faster?”

There is so much that can be done to achieve net zero carbon in advance of 2050, which could yet limit the worst of dangerous climate breakdown and leave our children a world that is still repairable. In 1941, following the Japanese attack on Pearl Harbor, the United States put its entire economy on a war footing in half a year; replacing production of sewing machines, cars and bicycles with the manufacture of tanks, aircraft and ships. Make no mistake, we are in a war situation now, and we need to act like it if we are ever to make a serious dent in greenhouse gas emissions and successfully tackle the climate emergency. However quickly global net zero arrives, though, we have to accept that our planet, in the decades and centuries ahead, will be a very different one. This means that at the same time as doing everything we can to slash emissions, we need to adapt to a world of blistering heat, more violent and destructive weather and far higher sea levels.

Cover more of our urban areas with plants: Ashe Conrad-Jones and Amy Van Den Broek from Pocket Forests tend to their installation in Dublin. Photo by Frank McGrath

We need, then, to be thinking hard about those specific changes to infrastructure and the way we lead our lives that will make our climate-changed future, and that of our children and their children, that much more bearable. New housing stock must be carbon neutral, heated by air-source or ground-source heat pumps, green hydrogen or microwave boilers, and insulated to keep the heat in during the winter months, and the growing summer heat and humidity out. Existing housing stock must be urgently retrofitted to meet similar requirements. To help combat the so-called ‘heat-island’ effect that makes cities several degrees warmer than surrounding rural areas, a ‘greening’ crusade is vital — more trees, more parks, and walls and roofs that are covered with plants.

The increased flood threat means that it would be madness to continue building on flood plains, while rapidly rising sea levels make a programme of managed retreat urgent if properties are not to be lost wholesale to the waves in the future. It is disturbing to consider that not much more than a two-metre rise in sea level — perfectly possible within 80 years — would result in the serious and permanent inundation of parts of Dublin, Limerick, Wexford, Cork, Shannon — including the airport — and other coastal communities.

Replacing the world’s billion or so fossil-fuel powered cars with electric ones is no answer to our problems, and brings serious resource issues of its own. On the other hand, investment in efficient, cheap, zero-carbon public transport such as battery, hydrogen or fuel-cell powered buses, trams and rail, will result in a lighter environmental footprint and better support the common good.

Agriculture will be hit especially hard on a hotter planet with more violent weather, and harvest failures are slated to become increasingly common. To compensate, more land will have to given over to growing crops to feed people rather than animals. The corollary of this, alongside a continuing trend towards lower meat and dairy consumption, will be far smaller Irish and UK national cattle herds. Those crops that are grown will need to be varieties that are as resistant as possible to growing heat and drought.

Taking in the bigger picture, national and global economies will struggle to function in the hotter and more unpredictable world that awaits us. Grim though this will be for most, one positive may be that we see an inevitable and welcome transformation from economies predicated on greed, short-term gain and profit to ones where supporting the greater good is the most effective way of surviving and making progress.

Indeed, such a shift may be the only chance we have of preventing an increasingly dangerous, climate-changed world mutating into one of catastrophic climate breakdown that threatens the very fabric of civilisation, and perhaps the survival of humanity itself.

Bill McGuire is Professor Emeritus of Geophysical and Climate Hazards at University College London. His latest book, ‘Hothouse Earth: An Inhabitant’s Guide’, is published by Icon Books

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