[Geomag-daily] Daily bad Total Field Values at Deadhorse Observatory

[Sauter, Edward]

All,
On a daily basis, starting at at random hours, there are a lot of missing 1
second F values.  Carol Finn first noticed the problem.  Not so many as to
corrupt our 1 minute values, but a fair number.  They seem to be
concentrated over a 1 -3 hour period, and in the later half of the UT day
(after 1300 during the last week or so).

Whatever is causing this problem, it took September 21 off.  During this
day, there was on 1 bad 1 second F value.

In order to see what I describing, you must view a time span of no more
than 30 minutes on the Geomag Plots page:
https://geomag.usgs.gov/plots/

On the left side of the page, you can select an individual observatory
(DED, for your observatory)

Also, on the left side of the page, there are 2 blocks that signify the
start and end time for the horizontal scale.  For example, enter a start
time of 2018-09-23 20:00:00, and an end time of 2018-09-23 20:30:00.
(within the time blocks you can edit the entry already there)

After selecting this time span, you can use the Step Forward and Step Back
'buttons' to shift the time span accordingly.

Because of the way this happens for a period of time, and on almost a daily
basis, I am of the opinion this is an artificial disturbance, and can be
remedied.  One of the more probable causes would be welding in the
vicinity, but it could be something else.

Please investigate at your first opportunity and by all means avoid taking
absolute observations during periods where the Total Field values are being
corrupted.

Some statistics:

Date

Starting at:

Bad 1 Second F Values

9/19

1300

170+

9/20

1300 UT

220

9/21

0100

1

9/22

2200

165

9/23

2000

500+

9/24

2200

168

9/25

2000

280+


Regards,
Ed Sauter
-- 
Edward A. Sauter
US Geological Survey
Box 25046 DFC, MS 966
Denver, CO 80226-0046 USA
E-mail: esauter at usgs.gov
Phone: 303-273-8471
Fax 303-273-8506
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