January 4, 2008 Space Weather Prediction Center (SWPC) Boulder-NOAA Magnetometer Data List This directory contains data lists of 1-minute magnetometer H- and D- component values from the Boulder-NOAA Magnetometer. For a 12-hour graph and 3-hourly indices web page see: http://www.swpc.noaa.gov/rt_plots/bou_12h.html The boumag_1m.txt file contains data for the last 2-hours and is update every minute. Users retrieving data frequently are requested to use the 2-hour files. The daily files (e.g. 20040210_boumag_1m.txt) contain data for that day and update once an hour. Daily files are kept online for 30 days. Date/times Dates are shown as year month day (2003 09 06) and "Modified Julian Day (MJD) as defined in an early SWPC database. The SWPC MJD for Jan 1, 2003 is 52640 The SWPC MJD for Jan 1, 2004 is 53005 Time is shown as HourMin (0035) and seconds of the day (2100) Boulder's geographic location is N40.1 W105.2 The values are the average of 60 1-second samples, time tagged with the beginning of the minute for the 60 samples. The H component is directed along magnetic north, which is currently about 10 degrees east of geographic north. The D component is pointing 90 degrees clockwise relative to H. This is currently about 10 degrees south of geographic east. ===================================================================== Users of the Boulder NOAA magnetometer data please note: Be aware that these data are real-time and are of a preliminary nature. NOAA makes no claims as to the absolute calibration of the data, and as such the data are available for users on an 'as is' basis. The Boulder-NOAA magnetometer data were compared with variations of the definitive USGS values for November, 2001, to evaluate the data quality. The results of that study show: standard deviation of the differences in the H-component is 4 nT standard deviation of the differences in the D-component is 2 nT Users should also be aware that there can on occasion be unexpected systematic shifts that are not always detected by SWPC in real-time. SWPC strives to correct these problems as soon as possible within the constraints of our operating capabilities. NOAA does have future plans to add a redundant instrument as a way to detect systematic errors as well as provide an operational backup system. ****************************************************************** ** Please read the SWPC Disclaimer at http://www.swpc.noaa.gov/ ** ****************************************************************** SWPC provides near-real-time and recent data, solar and geomagnetic indices and solar event reports created from preliminary reports. Preliminary data may contain errors or be revised after further review. The historical products in this SWPC Warehouse are the preliminary reports as originally published. SWPC does not encourage the use of preliminary data for research purposes. Links to on-line data at SWPC and archive sites with final data: http://www.swpc.noaa.gov/Data/ ****************************************************************** Please send comments and questions to SWPC.Webmaster@noaa.gov Report problems to SWPC.CustomerSupport@noaa.gov ******************************************************************************** ******************************************************************************** ************************************************ Sample Boulder Magnetometer List -- :Data_list: 20071102_boumag_1m.txt :Created: 2007 Nov 03 0010 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # Please send comments and suggestions to SWPC.Webmaster@noaa.gov # # Label: H - component = Magnetometer variations parallel to the # surface along the magnetic north-south direction. # Label: D - component = Magnetometer variations parallel to the # surface, transverse to H and eastwards. # Units: nanotesla (nT) # Source: Boulder NOAA Magnetometer # Missing data: -1.00e+05 # # 1-minute Boulder NOAA Magnetometer Components # # Modified Seconds # UTC Date Time Julian of the # YR MO DA HHMM Day Day H D #-------------------------------------------------------- 2007 11 02 0000 54406 0 -1.91e+01 -1.58e+02 2007 11 02 0001 54406 60 -1.91e+01 -1.58e+02 2007 11 02 0002 54406 120 -1.91e+01 -1.58e+02 2007 11 02 0003 54406 180 -1.90e+01 -1.59e+02 2007 11 02 0004 54406 240 -1.90e+01 -1.58e+02 2007 11 02 0005 54406 300 -1.90e+01 -1.58e+02 2007 11 02 0006 54406 360 -1.89e+01 -1.58e+02 2007 11 02 0007 54406 420 -1.88e+01 -1.58e+02 2007 11 02 0008 54406 480 -1.86e+01 -1.58e+02 2007 11 02 0009 54406 540 -1.85e+01 -1.58e+02 2007 11 02 0010 54406 600 -1.85e+01 -1.58e+02 2007 11 02 0011 54406 660 -1.86e+01 -1.58e+02 2007 11 02 0012 54406 720 -1.82e+01 -1.57e+02