Photo: Dave Walsh. More about this image here…
Suffering from global warming fatigue? Considering the 30 percent drop in attendance rate at the Irish Skeptics talk on climate change in April, some might. Understandably so. Not only because of this feeling of having heard it all before… but also, living in Ireland even if you’re one of the most environmentally concerned citizens, you might still find it hard to be really upset about the temperatures getting warmer. Rightly so? Well, this was actually the question addressed by Professor John Sweeney from the Department of Geography, NUI Maynooth in his talk “Climate change in Ireland: The need to move beyond skepticism”.
Professor Sweeney was invited by the Irish Skeptics as a member of the IPCC (the Intergovernmental Panel on Climate Change) to tell us about the likely consequences that climate change will have for Ireland.
It will maybe surprise some Irish people to hear that Ireland has played a significant part in the global warming story. Not in causing it though… we’re a bit too small for that. But Ireland was there at the very beginning, when the climate change story all started. We have to go back to the year 1976, when the World Meteorological Organisation sent four people to Geneva and locked them in a hotel room for the weekend. There they were assigned two key questions: was the climate changing, and if so, should we be concerned?
According to Prof Sweeney, these were pretty radical questions – at the beginning of the 1970’s climate change was not an issue at all. As it happened, one of the participants was an influential Irish figure, senator James Dooge, described by Prof Sweeney as “perhaps one of the most important, prolific and distinguished scientists of the past generation”. Nobody knows what was said in this room at the time, but the four emerged with their final conclusion: yes, the climate was changing, and yes, we should be worried.
So that’s how it all started, with a significant Irish contribution, after which the story we all know began to unfold. A decade or so later (1988), the IPCC was formed, a first report was published in 1990 and the consensus emerged. Another two decades or so later, all the people involved (including Prof Sweeney) got the Nobel Prize for Peace (2007) for the critical role they played in warning us about our planet’s frightening future.
At this stage we don’t need the IPCC experts to notice that the climate is changing. Changing landscapes, melting ice caps, shrinking lakes, it is pretty obvious that the earth is warming up. In Ireland however, it is not so obvious. Or is it? Prof Sweeney tells us that changes are noticeable in Ireland too, and does his best to convince us that we should be concerned…
Temperaturewise, what’s happening in Ireland has mirrored what’s happening globally, he says. The country has just been lagging a decade or two behind (probably due to its surrounding seas acting as a buffer). He points out that globally the warming rate was 0.74 degrees over the past century, and in the past 50 years it accelerated reaching 0.128 degrees per decade. These figures may not sound that impressive, but Prof Sweeney tells us Ireland is now warming up three times quicker than the global average… as if the country was trying to catch up.
You might not have noticed Irish summers getting warmer. This is because so far summer temperatures have mainly increased at night, by one degree or so. While that does not appear to be such bad news, Prof Sweeney warns us that warmer weather, especially during the summer, might have some unwanted health effects. “Food-born disease and water-born disease may become more of a problem as temperature rises”, he says, though “we won’t have malaria and we won’t have tropical diseases for a long long time in Ireland”, he reassures us.
He also reminds us of the 2003 heat wave in France, which caused 30,000 deaths. He agrees that in this country we’re not there yet. However, believe it or not, the warmest day of the decade, probably of the century, which was the 13th of July 1983 (very noticeable day where Kilkenny saw temperatures up to 32 degrees) was associated with an increase in mortality. And apparently, we do get more warm days than we used to.
Prof Sweeney points out that in the past 50 years the number of warm days has doubled. Note that the definition of warm days for this calculation was a mere 18 degrees. And anyway, it is pretty clear that Irish people dying from high temperature is probably not the biggest concern in relation to global warming.
If anything, we should be more concerned about people dying during the Irish winter. According to Prof Sweeney, Ireland has higher winter mortality rates than Scandinavia – most likely due to bad insulation and poor fuel usage. Luckily, this may be about to change as well, as temperatures have also been increasing during the winter – Irish winters are projected to be 2 to 2.5 degrees warmer by the middle of the century.
Prof Sweeney is actually talking about ‘Cork like’ winters for the whole of Ireland, or at least the midlands, which again may not be such bad news, he agrees. “According to our management model, a 2.5 degrees increase would decrease cold-related mortality by 2 to 3 percent”. In any case we could certainly do with one or two more degrees during the winter, couldn’t we? So it is rather welcome news also that, as explained by Prof Sweeney, while the number of warm days has doubled in the past half century, the number of very cold days has been halved.
However, Prof John Sweeney does not want to leave us on this happy note. He stresses that raised temperature is not the key issue as far as global warming is concerned (we should actually call it global change). In fact, the main concern is rainfall. And here he is not only talking about Ireland; he’s talking globally. Rainfall is definitely changing, getting more abundant in some areas of the planet – the continental temperate parts that could actually do with less rain – and rarer in others – the ones which could do with more (such as some tropical areas or already too dry developing countries). Ireland does not seem to escape the rule. Prof Sweeney goes on to say that “rainfall is actually the single most important element that we should worry about in Ireland in relation to climate change”.
Already, current observations are telling us that there is considerably more rainfall during the winter in the Irish Midwest region. “We noticed a huge increase in rainfall in North Donegal”, Prof Sweeney points out. And it’s unlikely we have got our measurements wrong. According to him, the country has among the best coverage in the world, with up to 500 rainfall stations. What’s more, the observed trend confirms the model predictions, which describe an 11 percent increase in rainfall by mid-century.
This means that the frequency of flood events will have to be recalculated. A one in a 50 year event could well become by 2050 a one in a 5 year event, and the Boyne river could end up overflowing every few years instead of every 25 years. Infrastructure will have to be built to cope with this.
While increased rainfall is a concern in the NW of Ireland, in the SW the trend seems to be the opposite. Rainfall is decreasing. So summers in the east of Ireland are going to be drier, Prof Sweeney says – or rather less wet – by 25 to 40 percent.
You would think this, along with the warmer winters, is positive; but according to him it is not – at least not for everybody. It’s not good news for potatoes, which unlike most of us love wet summer days, especially in August when they need water to swell the tubers. No wonder potatoes are so happy in Ireland. I know there is an intimate relationship between the Irish and potatoes, but personally I would not mind swapping a few potatoes for a few more sunny summer days.
Another victim of ‘drier’ summers would be cattle. “There is a significant risk that from the middle to the end of this century, farmers will have to keep the cattle indoors during the dry summer days”, says Prof Sweeney, “something completely unheard of in Ireland”. That’s because the grass is not going to grow so easily in the Emerald Isle, which sadly may become a bit less ’emerald’ than before.
A final concern in relation to climate change is the much discussed rise in sea levels. In countries such as Bangladesh one meter of sea level rise would engulf 100km of coastline. We don’t want to imagine how a similar event would affect Ireland. It is true that rise in sea levels may not be such a worry when looking at the tough rocky western coastlines such as the cliff of Moher… there is a bit of leeway there. However, soft sandy coastlines in the East are obviously more of a concern, as increased erosion and land loss would need to be coped with.
Somebody in the audience argued that he’d been living in Merrion Gate (near the sea) since he had been a child and has never noticed any change in the tide levels. This is a fair comment – why then can’t we see any major change happening? According to Prof Sweeney, this is because the land has also been rising since the disappearance of the ice cap, more or less compensating for the rise in the sea level. In the North of Ireland (above Galway-Dublin line) land is actually rising more dramatically, making it look as if sea levels are actually falling!
This becomes all a bit confusing, doesn’t it? Anyway the point is, whether we like it or not, the climate is changing rapidly and in some parts of the world very worryingly. Even tough Ireland may not be the worst, we had better do something about it, especially as we’re ‘pretty sure’ we (humans) are causing the change – as clearly stated it in the IPCC report*.
We might (or might not) manage to attenuate this trend. The oil shortage should help – if nothing else, running out of oil will definitely motivate us to find alternative energy sources and cut down on CO2 emissions. But in any case we will have to cope with the changes and adapt. It is most likely we will and humanity will survive. We have the technology, and we’ve certainly survived worse in the past two hundred thousand years of human existence.
Prof Sweeney hopes that our children in 50 years time will look back and say “thank God in 2009 they pulled themselves back together and began to address the problems in a realistic way”. But you could also imagine our Irish descendants, sunbathing under the palm trees of Dublin bay, and thinking: Gosh, those Irish people who lived here before us, how on earth could they have coped with the awful weather they had. And they would find it very hard to explain why we were so worried about it getting warmer. That would also be a fair comment, after all.
*Note that we’re not ‘completely’ sure about the human responsibility. Prof Sweeney explained that ‘pretty sure’ in the IPPC experts’ understanding means that they are sure at ’90 percent’. Mind you, this does not mean that 90 percent of them think it is human contribution and 10 percent think it’s just some natural process. Prof Sweeney was there when they decided on this 90 percent figure. Apparently there was an argument whether they should put down 90 percent or 95 percent, and they finally opted for 90 percent for ‘political reasons’… In statistics you need a 5 percent chance or less to decide that some hypothesis is unlikely to be true, which means that a 10 percent chance is not that unlikely after all… but as Prof John Sweeney put it, uncertainty is not an excuse for inaction. “Would you fly an airplane that is 90 percent certain to land?”, he says.
This article has been published in the September 09 issue of Science Spin.
This blog was published as part of Blog Action Day 2009
BTW, it’s worth pointing out that the IPCCâ€™s estimates (in 2007) for sea level by the end of this century didn’t really taking into account the contribution from the melting of ice sheets in Greenland and Antarctica because the dynamics of the melt were so poorly understood – even now, scientists are running to catch up.
Glacialogists and climatalogists (I’ve just spent four months working with some of them on Greenland’s ice cap, and the Arctic sea ice) are now conducting research that will help them unravel the complicated dynamics that govern and influence the melt of the enormous ice sheets at opposite ends of the planet, their predictions for the rate of sea level rise increase. The IPCCâ€™s 2007 estimate for sea level rise by 2100 is 20-60cm (8-24 inches). Since then, scientists predict sea level will rise one to two meters (3.3 to 6.6 feet)
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