salbers

Thanks for the tips. Does the "some" option then mean that only somewhat random points are shown? Maybe that could explain the Barrow extreme points not showing up. I tried the text file download though it isn't working for me yet.

Why are the older graphs showing up presently on the ESRL website then?

Since I work at ESRL, I should try walking down the hall to find out... Or the webmaster can probably be contacted...

All the images I posted were using surface flasks. This does not make any sense unless the reading was an error. One chart is newer than the other, perhaps the readings were bad and the reason it is variable depending on the start date is that one image is newer than the other. All the images showing no spike are newer than the one that showed the spike. I think the spike was an error, this post is basically proof.

Yes, the orange measurements aren't yet quality controlled. Curiously I only get the older plots from Dec 12-17 rather than the new one from Dec 28 (today) that you posted.

You can get different results depending on whether you select the less frequent surface flasks, or the more frequent daily in-situ measurements. I forget how often they do the surface flasks - maybe weekly?

Otherwise, your plots seem to match OK given only a change in the start date.

I got the image from a post Vergent made. http://www.americanw...ost__p__1223477

I tried to recreate the image off the site you linked and was unable to.

Vergent and I have the same link. For this link one still has to select the appropriate options.

My larger point is that maybe the Barrow readings aren't that unusual, and that local methane releases have been occasionally occurring over the years in that area?

Seems like the daily in-situ measurements at Barrow show variability and spike events over the years?

http://www.esrl.noaa...am=ccgg&type=ts

Marietta Wx - curiously when I look at the ESRL site I only see the Barrow CH4 plot updated on Dec 12 and it is missing the data point at 2100ppb. Do you have a link that yields the more updated plot? It's good practice to post a link along with an image when possible. Thanks.

http://www.esrl.noaa...am=ccgg&type=ts

In-situ daily averages show more scatter and that this scatter is a more common occurrence: