Already, 2023 is understood to have been the hottest year on Earth in the last 125,000 years — with temperatures averaging around 1.4C above pre-industrial.

800,000 Hiroshima-sized bombs every day

To try to grasp the magnitude of this heating, scientists calculated that in July 2023 — the hottest month in Earth history — the planet absorbed the equivalent energy from human actions as released by 800,000 Hiroshima-sized bombs every single day.

This colossal additional energy has provided fuel for epic weather disasters on all continents.

Record-smashing extreme heatwaves were recorded repeatedly across Europe, North America and much of Asia, and as the southern hemisphere swung into spring and summer later in the year, temperatures above 35C were recorded in South America — in its midwinter.

To understand just how extraordinary these heatwaves are, the temperatures being experienced from northern Argentina to Chile were 22-25C above normal for the time of year. In parts of Brazil, Paraguay, and Bolivia, temperatures breached 40C — in the depths of winter.

A study by the scientific group World Weather Attribution found that these freakishly hot conditions, that led to multiple deaths, were made 100 times more likely as a result of human-induced climate change.

Stronger El Niño effect expected this year

While the developing El Niño played a minor role in spiking 2023 temperatures, its impact is expected to be much more pronounced in 2024.

El Niño is a naturally occurring climate pattern of sea surface warming, originating in the Pacific Ocean.

Typically — in an El Niño year — global temperatures increase slightly, as more heat energy from the oceans enters the atmosphere.

The strengthening El Niño effect into 2024 has the power to turbocharge the global atmosphere, which is already heating quickly as a result of the rapid accumulation of greenhouse gases (GHGs) from human activity.

At the Cop21 conference in Paris in 2015, nations of the world agreed to limit the rise in global temperatures to “well below 2C” — aiming to hold the line at 1.5C. In the years since then, scientific evidence has underlined the extreme sensitivity of Earth systems to increased levels of GHGs.

At that time, it was still being projected that the world would not experience its first 1.5C year until into the 2030s. This has turned out to be entirely optimistic. While temperatures race forward, the political response to the crisis still moves at a glacial pace.

Little concrete progress at Cop28 

The recently-concluded Cop28 conference in Dubai managed to mention the phrase “fossil fuels” for the first time in its history. Beyond that, little concrete progress was made. Emissions reductions remain largely voluntary and left up to individual states to implement — or ignore.

While most politicians headed home from the conference largely satisfied with the non-binding nature of the process, how many of them will have read the State of the Cryosphere 2023 report?

This was produced recently by 60 top experts in the field and began with the stark statement: “We cannot negotiate with the melting point of ice”.

We are, the study warned, on the cusp of catastrophic sea level rises.

Melting polar ice could swamp Irish cities 

The cryosphere refers to the world’s frozen landscapes — from the poles to Greenland — and massive glaciers such as in the Himalayas, as well as permafrost. “From the cryosphere point of view, 1.5C is not simply preferable to 2C or higher, it is the only option”, the report noted.

Failure to drastically cut global carbon emissions locks in humanity to centuries of catastrophic sea level rise, of a scale and at a rate that will be impossible for societies to adapt to.

The central conclusion of the cryosphere report is that if temperatures are allowed to reach 2C, it will trigger an irreversible collapse of the world’s major ice shelves — leading to the inundation and loss of much of the world’s coastal settlements and infrastructure.

For Ireland, this would mean the gradual abandonment of much of Dublin, Cork, Limerick, Wexford and Galway. Put simply, this cannot be allowed to happen.

Yet politicians, lobbyists, and corporations are carrying on with the delusional conceit that we can cobble together some kind of last-minute compromise with the laws of physics.

Deadly heat all over Europe last summer

After the blistering European summer heatwaves of 2022, deadly heat returned to the continent in 2023 — with the mercury hitting 45C in areas of Spain and across the Mediterranean in mid-July last.

Many Irish tourists found themselves in “unbearable” temperatures in traditional European holiday spots.

The flip side of high temperatures are extreme flooding events. The most severe of these occurred when Storm Daniel ripped into Libya in September 2023, killing an estimated 20,000 people — with many deaths attributed to the collapse of a poorly maintained dam.

Analysis by World Weather Attribution found that the devastation in Libya was made far more likely and worse by climate change. Reconstruction costs are expected to run into billions of dollars.

There was much fanfare at Cop28 at agreement having been reached on a Loss and Damage Fund to help compensate countries being impacted by climate change, yet the total (voluntary) commitments to this fund run to around $700m.

As Libya illustrates, this is a drop in the bucket for a single country — let alone as a global fund.

Storm Babet gave Ireland a taste of extreme weather

Ireland received a taste of extreme weather when Midleton, Co Cork, was hit by a severe flooding event in October.

Storm Babet dumped over a month’s rainfall on the area in a 24-hour period, leading to millions in damage.

For every 1C rise in global temperatures, the atmosphere can hold an additional 7% of water vapour, and Ireland’s rainfall has increased by this amount in just the last 30 years — in line with rising temperatures.

What is becoming increasingly clear is that, while engineering solutions can work in limited instances, the only longer-term way to safely manage increased precipitation in Ireland is to employ nature-based solutions — such as restoring uplands and paying farmers to allow their fields in floodplains to flood, as nature intended.

In some cases — however — it will be simply impossible to defend properties and infrastructure, and a planned retreat from high-risk areas is inevitable.

We may have already breached tipping points

It is astonishing to consider that all 10 of the hottest years ever recorded on the instrumental record, stretching back to the late 1800s, have all occurred since 2012. The chance of this sequence being a coincidence is less than one in a billion.

The problem with tipping points is that, because of system inertia, you can have breached one or more without the true impacts being immediately apparent. All we know for sure is that we are already in a parlous situation.

And 2024 promises to be yet another year of living dangerously. While we should be tip-toeing carefully along, humanity continues instead to blunder forward more quickly than ever — wandering deeper and deeper into a veritable minefield of climate impacts.

Will our luck finally run out in 2024 or, like in the movies, will we engineer an unlikely last-minute escape? Time will tell.

• John Gibbons is an environmental journalist and commentator