Clarification on weather statistics


A misleading headline related to weather statistics is causing a bit of traffic on Twitter and I want to clarify the issue.

We have altered the headline online to better reflect what the article is trying to say.

The weather stats released by Met Éireann are 30 year means. They allow the forecasters to put daily weather in some kind of context: it is warmer than usual, there was more sunshine this month than the average, this was the coldest May since etc, etc.

These 30 year means are not capable of telling us anything new about global warming one way or the other. They were not designed to do so and in any case would be a tiny data set upon which to make any extravagant claims.

The one thing you can take from these 30 year averages is that the newer data set shows that on average temperatures are now higher when compared to the previous data set.

Met Éireann head of forecasting Gerald Fleming does however have something useful to say about this increase, which depending on how you look at the stats is between 0.5 degrees C and 0.75 degrees C.

If average world temperatures rise by three to six degrees C by the end of the century, then the increase seen in the Irish 30 year means matches up very well with the 3-6 degree projected temperature increase.

The Irish Times Logo
Commenting on The Irish Times has changed. To comment you must now be an Irish Times subscriber.
The account details entered are not currently associated with an Irish Times subscription. Please subscribe to sign in to comment.
Comment Sign In

Forgot password?
The Irish Times Logo
Thank you
You should receive instructions for resetting your password. When you have reset your password, you can Sign In.
The Irish Times Logo
Screen Name Selection


Please choose a screen name. This name will appear beside any comments you post. Your screen name should follow the standards set out in our community standards.

The Irish Times Logo
Commenting on The Irish Times has changed. To comment you must now be an Irish Times subscriber.
Forgot Password
Please enter your email address so we can send you a link to reset your password.

Sign In

Your Comments
We reserve the right to remove any content at any time from this Community, including without limitation if it violates the Community Standards. We ask that you report content that you in good faith believe violates the above rules by clicking the Flag link next to the offending comment or by filling out this form. New comments are only accepted for 3 days from the date of publication.