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by fyfy18 3035 days ago
Another commenter posted a link to climate data from the Danish Meteorological Institute for the artic region for the past 50 years:

http://ocean.dmi.dk/arctic/meant80n.uk.php

For most of the dataset the winter temperatures have followed the model fairly well (of course there are spikes), but for the last few years the winter temperature has been significantly higher than the model.

1 comments

The "of course there are spikes" is the whole reason I'm commenting in this thread. If there are spikes (if spikes are the norm) then the article that has been posted is not news. News is something anomalous, no?

Not news: "there's been this major spike the last few days! (oh btw, there have always been spikes)"

Sort of news: "there's been this major spike the last few days! the severity of the spike is fairly unprecedented, it happens once every 50 or 100 years"

Worrying news: "there's been this major spike the last few days! these have been happening more and more frequently. they have been getting more and more sever. increase in frequency is X%, the increase in severity is Y%. these increases have been going on for Z years. this falls outside climate change variability by V%.

Alarmist news: "there's been this major spike the last few days! omg, climate change!"

That Danish data set you linked to. Have you have noticed that the numbers jump around at the edge of the year? Check out the break between 1999 and 2000. I can see by eyeballing it that the winter temperature has been somewhat (not significantly) more erratic (not higher) than the model which is 1958-2002. How much more erratic though? I don't want you to interpret the data for me using your words, I want the percentage differences themselves. I'll make up my own my mind about what words to use to describe the variability if that's okay with you.

Here's what it says, “Calculation of the Arctic Mean Temperature The daily mean temperature of the Arctic area north of the 80th northern parallel is estimated from the average of the 00z and 12z analysis for all model grid points inside that area. The ERA40 reanalysis data set from ECMWF, has been applied to calculate daily mean temperatures for the period from 1958 to 2002. From 2002 to present the operational model (at all times) from The ECMWF is used for mean temperature calculations.”

So we're getting one number for everywhere north of the 80th parallel? What are the 00z and 12z analysis?

The document they link to explaining the methodology leaves me with more questions than it answers: http://ocean.dmi.dk/arctic/documentation/arctic_mean_temp_da...