Errors in publicly presented data – Worth blogging about?

Watts Up With That?
Tuesday, Feb 17, 2009

In the prior thread I raised a question of why there was a large downward jump in sea ice extent on the graph presented by NSIDC’s Artic Sea Ice News page. The image below was the reason, dozens of people called my attention to it in emails and comments overnight because in the space of a weekend, a million-plus square kilometers of Arctic sea ice went missing. Note the blue line.

Click for larger image

When I checked NSIDC’s web site this morning, about 8:30 AM PST  (9:30AM MST Mountain time in Boulder where NSIDC is located) the image was still up. A half hour later it remained. I checked all around the NSIDC web site for any notice, including the links they provide for the data issues.

Learn about update delays, which occasionally occur in near-real-time data. Read about the data.

Finding nothing, and knowing that it was now 10AM in Boulder, which should have been plenty of time to post some sort of notice, I decided to write a quick post about it, which was published at 9:10AM PST (10:10MST) and drove to work.

The corrected image (with the million square kilometers of sea ice restored) appeared on the NSIDC web site just shy of  3 hours later, about noon PST or 1 PM MST.

Click for larger image

About the same time this comment was posted on WUWT by NSIDC’s chief research scientist, Dr. Walt Meier:

Anthony,

We’re looking into it. For the moment, we’ve removed the data from the timeseries plot.

You need to remember that this is near real-time data and there can be data dropouts and bad data due to satellite issues. While the processing is automatic, the QC is partly manual. Thus errors do happen from time to time and one shouldn’t draw any dramatic conclusions from recent data.

I’m not sure why you think things like this are worth blogging about. Data is not perfect, especially near real-time data. That’s not news.

ps – FYI, the JAXA data is from a different sensor, so it is not consistent with our data, but it provides a good independent check. If the JAXA data does not show a dramatic change while the NSIDC data does (or vice versa), then it’s likely an issue of missing data or bad data.

First let me say that I have quite a bit of respect for Dr. Meier. He has previously been quite accessible and gracious in providing answers, and even a guest post here.  But I was a bit puzzled by his statement “I’m not sure why you think things like this are worth blogging about…. That’s not news“

(ARTICLE CONTINUES BELOW)

 

First let us consider a recent event. The BBC ran really badly researched video report just a couple of days ago where the reporter obviously didn’t know the difference between positive and negative feedbacks in the climate. I wrote about it. The video is now gone. Now I ask this question; if nobody speaks up about these things, would the video still be there misinforming everyone? Probably.

The point I’m making here is that in my experience, most reporters know so little about science that they usually can’t tell the difference between real and erroneous science. Most reporters don’t have that background. I say this from experience, because having worked in TV news for 25 years, I was always the “go to guy” for questions about science and engineering that the reporters couldn’t figure out. And, it wasn’t just at my station that this happened, a meteorologist friend of mine reported the same thing happened to him at his station in the San Francisco bay area. I vividly remember one week he was on vacation and I saw a news report about a plane that crashed that had just minutes before been doing a low level run over the airfield as part of a show. The reporter had video taped the plane’s run, and then used that video to proudly demonstrate “as as you can see, just minutes before the crash, the propellers on the plane were turning very slowly”.

The reporter didn’t understand about how a video camera scanning at 30 frames per second can create a beat frequency that give the impression of slowly turning propellers that were actually running about 3000 RPM., and there was nobody there to tell her otherwise. She made an honest mistake, but her training didn’t even raise a question in her mind.

So when I see something obviously wrong, such as a dramatic drop in sea ice on a graph presented for public consumption, I think about a reporter (print, web, or video -take your pick) somewhere in the world who may be assigned to do a story about sea ice today and does an Internet search, landing on NSDIC’s web site and then concluding in the story “and as you can see in this graph, Arctic sea ice has gone through a dramatic drop just in the last few days, losing over a million square kilometers”.

Thinking about Walt’s statement, “ That’s not news” if the NSIDC graph had been picked up by a major media outlet today, would it be news then?

I understand about automation, about data dropouts, and about processing errors. I run 50 servers myself and produce all sorts of automated graphics output, some of which you can see in the right sidebar. These are used by TV stations, cable channels, and radio/newspaper outlets in the USA for web and on-air. While those graphics are there on WUWT for my readers, I also have an ulterior motive in quality control. Because I can keep an eye on the output when I’m blogging. When data is presented for public consumption, in a venue where 24 hour news is the norm, you can’t simply let computers post things for public consumption without regular quality control checking. The more eyes the better.

At the very least, a note next to NSIDC”s Learn about update delays, about how glitches in satellite data or processing might generate an erroneous result in might be in order. And also for consideration, adding a date/time stamp to the image so it can be properly referenced in the context of time.  This is standard operating procedure in many places, why not at NSIDC?

NSIDC and other organizations need to realize that the interest in what they produce has been huge as of late. In NSIDC’s case, they have been promoted from relative obscurity to front page news by the recent unfortunate statements of an NSIDC employee, Dr. Mark Serreze, to the media, that have received wide coverage.

As commenter “just want truth” wrote in the previous thread on NSIDC:

Last year Mark Serreze, of the NSIDC (you may know him), said North Pole ice could be gone in the summer of 2008. He said then “The set-up for this summer is disturbing”. This, of course, was broadcast in all news outlets around the world. Everyone on both sides of the global warming debate was watching Arctic ice totals last summer to see what would really happen. You may have noticed hits on the NSIDC web site were high last summer.

Now Mark Serreze is saying North Pole ice is in a “death spiral”.

You can be certain that Arctic ice data will be scrutinized because of Al Gore and Mark Serreze. A line has been drawn by both. Both have placed it clearly on the radar screen. This is why NSIDC data is worth blogging about–especially since Mark Serreze is employed at the NSIDC.

Mark Serreze 2008 North Pole ice free :

http://abcnews.go.com/Technology/Story?id=4728737&page=1

and

http://www.youtube.com/watch?v=S6e3e4VzwJI

Mark Serreze North Pole ice in “death spiral” :

http://www.youtube.com/watch?v=HW9lX8evwIw

and

http://www.nypost.com/seven/08282008/news/worldnews/arctic_ice_in_death_spiral_126443.htm

Given the sort of attention that has been heaped on NSIDC, I think blogging about errors that have gone unnoticed and uncorrected by 10AM on a Monday morning isn’t an unreasonable thing to do.

I also think that reining in loose cannons that can do some terrible damage in the media is a good way to maintain scientific credibility for an organization, especially when predictions like “ice free north pole” don’t come true.

I have no quarrel with Dr. Meier, as I’ve said he’s been the utmost professional in my dealings with him. But I do have quarrel with an organization that allows such claims to be broadcast, all the while producing a data source that is now regularly scrutinized by the public and the media for the slighest changes. It’s a slippery slope.

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