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<span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; font-weight: 400; color: rgb(0, 0, 0);">The USGS Geomagnetism Program's Adjusted Data (aka "Provisional" by INTERMAGNET) provides near real time absolutely calibrated and geographically
oriented geomagnetic observations. These calibration parameters are usually updated on the first of each month in order to satisfy geomagnetic observatory standards for accuracy and quality control. Updates are deployed at midnight UTC, and may result in noticeable
baseline shifts for observatories whose sensor response characteristics may have changed substantially since the last such update, or in rare cases, whose actual sensor has been altered or replaced since the last update. To view the results of this month's
update, go to:</span><br>
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<div><span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; font-weight: 400; background-color: rgb(255, 255, 255);"><a href="https://geomag.usgs.gov/plots/?timeRangeType=custom&endTime=2023-05-01T00:30:00.000Z&startTime=2023-04-30T23:30:00.000Z&type=adjusted&scale=Trace" data-auth="NotApplicable">https://geomag.usgs.gov/plots/?timeRangeType=custom&endTime=2023-05-01T00:30:00.000Z&startTime=2023-04-30T23:30:00.000Z&type=adjusted&scale=Trace</a></span><br>
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<div><span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; font-weight: 400; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);">Noteworthy issues to report in this notice:</span></div>
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<span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; font-weight: 400; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);"></span>The
<b>Tucson (TUC) observatory adjusted data processing was reactivated</b> after being offline during a magnetometer upgrade.</li><li style="font-size: 12pt; font-family: Calibri, Arial, Helvetica, sans-serif; color: rgb(0, 0, 0);">
The <b>Deadhorse (DED) observatory adjusted data processing was deactivated</b> once again after receiving an insufficient number of reliable absolute calibration measurements since December 2022 to be confident in the geographic orientation of the instrument.</li></ul>
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