ANOTHER LIFE:THE BOGS crack open . . . the mountain lakes dry up . . . the sand dunes are being washed away . . . It's odd to be told what will happen to the landscape in the decades after I've gone – some sort of first, indeed, for homo sapiensof any age – if not, let us hope, some sort of last. How tantalising for James Lovelock, now 90, not to know how right he'll be about the final, feuding knot of humanity ending up somewhere in Lapland.
For the ancient oracles, mystery was part of power. For today's computer gurus, smoke and mirrors won't do, or they could be exposed behind the curtain like the little lever-puller in The Wizard of Oz. In Climate Change: Refining the Impacts for Irelanda report for the Environment Protection Agency, Maynooth geography professor John Sweeney and his 10 project partners leave no doubt that they had to be marvellous at maths and, once supplied with all the variables, marvellous at minding mice at crossroads.
They still face, as they say, “a cascade of uncertainty”, which can sometimes lead them into Delphic utterance. “One established method for uncertainty analysis,” offers the chapter on water resources, “is the Generalised Likelihood Uncertainty Estimation (Glue) procedure . . . ”
However, “the ability to attribute probabilities to impacts offers huge potential to decision-making approaches, with risks defined as the probability of hazard times the vulnerability.”
For such a small island so open to the ocean, the coming range of climate across Ireland will be quite dramatic, as summer droughts parch the east and south, while the west keeps more than its share of soft days.
It’s the threat of major floods that most alarms our engineers, and predictions of their frequency are offered for nine Irish rivers as the century wears on. While the Moy, in the north of my adopted county, will hang on to its water in summer rather better than, say, the Barrow, Blackwater or Boyne, its biggest floods could have doubled in size by the 2080s.
How do you “downscale” global scenarios to predictions for a single Irish river? Until recently, says Prof Sweeney, it was common to work with only one climate-change scenario derived from a single global model.
With better computing resources came regional climate models, giving detail down to 10s of kilometres. Prof Sweeney dips into a whole ensemble of scenarios to average and distil the likely likelihoods.
The new report goes beyond simple impacts of climate change on plant growth to weigh up what this actually means for farming. For example, more CO2 in the air can make plants need less nitrogen – so long as they have enough water. What does this say about the need to fertilise and irrigate? For potatoes, at least, the best and most profitable place to grow them will be in Donegal. Such juggling of variables marks the whole chapter on farming, even to the slurry surplus that will come with all the extra grass.
Initial responses of wild plants are expected to be “rather subtle”. There’ll be increases in bulk – the billowing biomass of summer that crowds the garden path – and changes in the species that normally grow together. How trees behave depends a lot on where they are, but some Irish trees are bursting into leaf 30 days earlier than 30 years ago. This can make problems for wildlife whose lives are synchronised with stages of tree growth and development.
We have far better records for the seasonal behaviour (phenology) of plants than for the island’s animals or insects. This brings special value to Nature’s Calendar, the network for observations provided by Paul Whelan at his brilliantly presented website (www.biology.ie), and now strongly endorsed by the EPA report.
The pace of change in the natural countryside will be far too rapid for adjustment in many species that live in specialised habitats.
While some may be able to migrate along remaining “wild” corridors, it shocks to be told that, by mid-century, the few fens we have left could be reduced by 40 per cent, with similar losses of bogs and even more of turloughs. This comes from calculation of “climate envelopes” of rainfall, humidity, temperature and so on, that allow such habitats to exist.
“Irish peatlands,” comes the flat judgment, “will progressively lose their current available climate space.” The cracking of peatland at the height of summer droughts will probably begin on the raised bogs of the east and on the peat slopes and summits of the Comeraghs and Wicklows. On Mweelrea, in my window, it will probably take longer for the whins to creep up in a golden wave. I don’t know which is more uncomfortable – to think that the world will just rumble on regardless, as in some Edwardian pastoral, or to know one will miss some profound events that one would quite like to have seen.
Eye on nature
I had a pair of blackbirds, with five three-day-old chicks, nesting eight feet off the ground in a thick evergreen bush in my garden. On my return home after the May bank holiday weekend I discovered the nestlings dead on the ground, in a semi-circle at a radius of six feet from the nest. The nest was not damaged, nor accessible to cats, and not visible from above. The chicks were not damaged, but just seemed to be carried from the nest and dumped.
Alan O’Dwyer, Carlow
On a walk up the Maumturk Mountains behind Lough Inagh Lodge Hotel, in Recess, Co Galway, I spotted a bird a bit smaller than a blackbird, with dark-brown plumage, red markings at its throat, and a white bar, like a splash of paint, above its tail.
Patrick Palmer, Firhouse, Dublin 24
It sounds like a stonechat.
In mid-April, on Inishbofin, Co Galway, I saw two whooper swans grazing in the field by the lake near the cemetery on the way to east village. I thought they should have been gone by then.
Eamonn Carolan, Westport, Co Mayo
According to Tim Gordon'sBirds of Inishbofin , whoopers are generally short-stay visitors to the island. Some whoopers wait until April before leaving.
Michael Viney welcomes observations at Thallabawn, Carrowniskey PO, Westport, Co Mayo. E-mail: viney@anu.ie. Include a postal address.
