In James Joyce's famous book, Dubliners, there is an interesting passage from my favourite short story in the book, An Encounter:
He stopped when he came level with us and bade us good-day. We answered him and he sat down beside us on the slope slowly and with great care. He began to talk of the weather, saying that it would be a very hot summer and adding that the seasons had changed greatly since he was a boy—a long time ago.
Is there any veracity to this ? If we assume that this slice of oral history is based on Joyce's own childhood reminiscences, then we can work out what period the old man in the story is referring to. Dubliners was written in about 1904 and this particular story is about two boys mitching off school. James Joyce was born in 1882 which would mean he would have heard this bit of oral history around 1890-1895. If we assume the old man was in his seventies at the time, then this would put him being born around 1820. We can then test his claim by referring to the temperature record from Armagh, one of the longest temperature records on the planet :
Figure 7 shows that the pre-1820 period was cooler than the period that followed:
The above paper concluded :
Long-term trends are seen in both seasonal and annual mean temperatures, with spring and summer series relatively flat compared with autumn and winter. Prior to 1820 we note that autumns and winters were cooler by ∼1 °C. Later, we note a significant warming in the mid-19th century, which started in the late 1820s and continued till c. 1870. A cool interval at the end of the 19th century was followed by a period of rising mean temperatures that lasted till the mid-20th century. Finally, a slight cooling from 1960 to 1980 was followed by a gradual warming over the past two decades. In spite of the current warmer conditions, annual mean temperatures still remain within the range seen in the previous two centuries.
The Valentia temperature record is the most reliable source as it provides data not compromised by urban heat :
So we can see that the temperature rose consistently above 11C in the 1990s and 2000s but there were periods in the past when it exceeded 11C aswell so we are still within ranges that people in Joyce's time experienced. Indeed, if we look at the latest annual mean temperature records from Valentia we can see that last year we were barely at 11C. While this year we are just over 11C at the time of writing with December turning out colder than the previous three years. So there is nothing terrifically extraordinary about recent temperatures in Ireland :
Mean temperature in degrees Celsius for Valentia_Observatory
There is an interesting article on the Armagh observatory website that puts the climate debate into context and explains just how complex Earth's climate system is. For example, scientists are still unsure as to what role clouds play in our climate :
The clouds are a main character in the climate scene, however their detailed role is yet to be determined. Climate models do not know how to deal with them. They play a double role, one the one hand they are bright and they reflect part of the radiation coming directly from the Sun back to space, having a cooling system because less energy arrives to the Earth surface. But on the other hand the Earth releases to space energy too and clouds can act as a blanket, trapping that radiation which should have escaped to the space in the same way as the greenhouse gases. Which of the two effects is going to dominate depends on the type and altitude of the cloud. Thus assessing their role in climate becomes nightmarish.
Of course, the sun also plays an important role in the climate system and the period that the old man grew up in is known as the Dalton Minimum, a period of low solar activity that lasted from about 1790 to 1830. This then accounts for the cool period that we saw above in the Armagh records.
Indeed, the old man would have lived through the transition of The Little Ice Age, a period of cooling that occurred between circa 1550 and 1850. NASA claim that this period was marked by a rapid expansion of mountain glaciers in Ireland. So the end of the Little Ice Age would have been a recent memory for the older generation by the time of Joyce's birth in 1882.
We can see from the above graph that the climate has (surprise, surprise) always been changing. In the 1970s, when Tim Severin recreated Saint Brendan's voyage in the Atlantic, which occurred in 512-530AD, numerous references were made to the warmer climatic conditions Brendan experienced. This period is known as the Medieval Warm Period and the North Atlantic, where Brendan sailed to, was warmer than today. This allowed the Vikings to travel further north than had been previously possible because of reductions in and land ice in the Arctic. One wonders, if Tim Severin tried to publish his book today, when climate alarmism has become fashionable, if the climate police would be set on him.
So we can see that there was indeed veracity to the old man's claim in Dubliners, that it was cooler when he was a boy, and that it had warmed up in Joyce's time. Perhaps An Encounter was indeed based on some of Joyce's reminisces as a boy and the stories he heard growing up in Dublin.