In 2025, Ireland has become a warmer, sunnier place and the weather forecast is always right, writes meteorologist Brendan McWilliams.
A week may be a long time in politics, as Harold Wilson remarked, but in climatology a quarter of a century ought to be a mere heartbeat. Or so we thought 50 years ago. But, looking back from this vantage point of January, 2025, it is clear that the past two decades have brought dramatic changes to our weather patterns.
The risks were well known. It became evident early in this century that the Kyoto Protocol, despite widespread support, would never work. Emissions of greenhouse gases have climbed from around 7 billion tonnes annually in 1990 to 12 billion tonnes today. We now have an atmosphere which contains 450 parts per million of carbon dioxide, compared with 350 ppm at the turn of the century, and double the concentration which existed before the industrial revolution began 200 years ago.
It became apparent during the 1990s that, as a result, the average global temperature was rising at a rate unprecedented in the previous 10,000 years. This has continued, and in Ireland in 2025 our average annual temperature is now nearly two degrees higher than in the middle of the 19th century, and a degree higher than 25 years ago.
We escape, in general, the scorching heatwaves that have become the scourge of central and southern Europe in the past decade or so, but lengthy interludes of warm, sunny weather have become a regular feature of the meteorological calendar in Ireland, rather than being the anomalies they used to be. The downside has been the droughts; we have come to expect an inadequate amount of summer rainfall, and shortages of water for competing domestic and agricultural use have created tensions between town and country dwellers.
But not many feel sorry for the Irish farmers. The market for our agricultural produce has increased steadily during the 2020s as yields from the parched soils of southern Europe have gone down dramatically, year on year. Irish crops, by contrast, have thrived in their new warmer and virtually frost-free environment, their yields further enhanced by the CO2-rich atmosphere. Farmers have had to take important strategic decision in recent years, switching from crops such as potatoes, which do not like our new, dry summers, to maize and soybeans, which love the new regime. Grassland and forest fires, on the other hand, have become much more frequent.
Fears around the beginning of the century that an influx of nasty foreign diseases would wipe us all out have so far proved unfounded. Although malaria and other mosquito-borne diseases have made a vibrant re-appearance in southern Europe, here in Ireland our epidemiology has changed little. Interestingly, there has been a small but significant increase in the number of deaths from food-poisoning in recent decades, but this has been more than compensated for by the several thousand fewer fatalities from hypothermia, because of our very mild winters.
Our tourist industry, also, has done well. This can be explained by the fact that many of the world's favourite sun spots of half-a-century ago, such as the south of France and southern Spain, have become unbearably hot in the summer months of July and August. Not only do an increasing number of our own holiday-makers prefer to stay at home and enjoy dependable Irish summer sunshine, but our European neighbours now no longer think of an Irish summer in terms of cool winds and incessant rain. The decline over the past decade of the winter holiday market, consequent on shrinking glaciers and a dearth of natural snow in Alpine regions, has also helped our tourist industry.
But our winters as we enter the second quarter of the 21st century are more problematic. They are mild - our last white Christmas was back in 2004 - but while we do not get as many storms, those that do come are much more severe than 20 years ago. Moreover, in a warmer world, in contrast to our perennial summer droughts, winter rainfall is now 20 per cent higher than it was a quarter of a century ago. Much of this comes in short, heavy falls that aggravate the frequent incidents of inland flooding that have become a major issue.
Coastal flooding, too, is now a major problem. Mean sea level in 2025 is a full 10 centimetres higher than it was at the turn of the century, which brings regular spring-tide flooding to Waterford, Wexford and certain coastal suburbs of Dublin on a scale unimaginable 20 years ago. Moreover, thousands of hectares of the "soft" coastlines of the east and south have been swept away in coastal erosion during storms over the past decade.
During the first years of the 21st century, policies on coastal erosion tended to focus on engineering solutions to provide increased protection for vulnerable areas. More recently, however, there has been an increasing realisation that such efforts were at best futile, and at worst conducive to even greater damage at other places up or down the coast. The emphasis nowadays is on demographic measures to avoid sensitive structures being built on vulnerable coastlines, after which nature, by and large, is allowed to take its course. But at least our ability to cope has been greatly enhanced by the increased accuracy of weather and hydrological predictions; now, in the 2020s, accurate forecasts of the day-to-day weather, and of inland and coastal water levels, for up to three weeks ahead have become the norm.
Looking back, we can see that global warming has brought us both heartaches and significant advantages. But the worst scenarios have not materialised. Older readers may remember the 2004 film The Day After Tomorrow which presented a chaotic, apocalyptic view of a frozen, blizzard-ridden, northern hemisphere consequent on a "switching off" of the warm northward-flowing waters of the Gulf Stream. Thankfully, this never happened - well, not yet, at any rate.