Recent Irish weather extremes and climate change

Su Campu

Here's an article dealing with the recent extreme weather events in Ireland (november rainfall and winter cold spell) and their relation, or lack therof, to climate change.

Basically they were part of natural climate variability.

http://www.met.ie/news/display.asp?ID=77

In November 2009 Ireland experienced unusually wet weather that caused widespread flooding. It was followed by a cold spell from mid-December that culminated in exceptionally wintry conditions in the early days of 2010. Both events have led to speculation that this is a manifestation of man-made climate change, a foretaste of what is to come. Is there any substance to this view or are the events explainable in terms of natural, as opposed to anthropogenic (human-induced), variability of the Irish climate?
Climate models suggest that extreme rainfall events, such as occurred in late 2009, are likely to become more frequent in the future, with additional changes in the average rainfall. These changes will be projected on the natural variability of the climate system, a fundamental feature that can produce large departures from the average. It is not possible to attribute any specific weather events to either of these components. The November 2009 rainfall was likely to be part of natural variability, supplemented with a small expected increase in rainfall due to anthropogenic climate change.

Similarly, the 2009/2010 winter cold spell was consistent with the natural climate variability displayed in the climate records.

WolfeIRE

which one are you Su...Ray McGrath, Rowan Fealy or Tom Sheridan?:p

Graces7

An old saying,,"Damn lies and statistics.."

Different "experts" will "interpret" the same figures in different ways...

Su Campu

Graces7 wrote: »

An old saying,,"Damn lies and statistics.."

Different "experts" will "interpret" the same figures in different ways...

Strange comment. Are you saying they're wrong? Do you think there was another reason for these events?

thetonynator

Su Campu wrote: »

Strange comment. Are you saying they're wrong? Do you think there was another reason for these events?

Once in a lifetime events have to happen at some point in your lifetime! I would think that it is coincidence that the floods were followed by the big freeze. However, if we were to have a similar situation this winter, I would be more likely to think it had something to do with climate change.

Deep Easterly

Graces7 wrote: »

An old saying,,"Damn lies and statistics.."

Different "experts" will "interpret" the same figures in different ways...

I agree with that in part, esp regarding interpretations of stats. An average is often considered (often by myself) as a 'normal', but in reality an avearge is only a pseudo-truth; the extremes that make up an average over time are actually more normal! The normal or average the extremes either side create are actually made out to be the deviations which can seem confusing at the best of times!!!

But what cannot be denied is just how wet last November was, even by normal deviational standards.

Speaking only from a local western perspective, Claremorris monthly rainfall total for November 2009 was unusually high compared to the any other november in the last 30 years (and beyond) as the below chart indicates:



a huge spike there in 2009 with monthly total for that year above 280mm.


Another interesting stat (I know, I'm a stats hoor! :o) is that despite November's wet spell, the 1981-2010 November rainfall average total is likely to be lower than that of the 1971-2000 average and most likely be closer to that of the 1961-1990 November average total which is still beng used today:

Graces7

Su Campu wrote: »

Strange comment. Are you saying they're wrong? Do you think there was another reason for these events?

Maybe, maybe not. Simply that if someone has for example a huge belief in global warming, then they will seek and emphasise weather that proves that and vice versa.

As for extreme weather events in Ireland; a reading of the Annals of the Kings/Four Masters etc will show that none of this is really unusual. ( available online in modern English)

As a rather old historian I maybe see these things from a different angle.

Danno

Funny thing is... cold always follows heavy rains.

Joe Public

Danno wrote: »

Funny thing is... cold always follows heavy rains.

But not an indicator of future weather.

riffmongous

thetonynator wrote: »

Once in a lifetime events have to happen at some point in your lifetime! I would think that it is coincidence that the floods were followed by the big freeze. However, if we were to have a similar situation this winter, I would be more likely to think it had something to do with climate change.

Agree, well maybe if we get 5 in the next 10, although even then you could argue about it statistically

gbee

Don't forget everybody that we are in a global shift of weather patterns, the same events that ultimately cause the 1930s dust bowl are here again, threatening another dust bowl in the USA.

This also reduces the Tornado activity, and shifts the storm fronts into less favourable conditions. It has also been protecting our own coast from the most extremes of the bad weather thrown our way in the last two years.

You'll notice how we've been just missing the worst of everything.