Minimize Auxiliary (AUX) Product Definitions
Contents

Specification of Auxiliary Products

This section describes the product name convention and the product classification.

Product Name Convention

According to [AD-13], Swarm product names consist of 10 digits, which are subdivided into two sub-fields as follows: TTTTTTTTTT = FFFFDDDDDD, where FFFF = File Category and DDDDDD = Semantic Descriptor. For Level 2 (L2) products FFFF = FFFx, where FFF describes the product type (e.g. AUX - Auxiliary Product) and for the single satelitte x = A, B or C for Swarm A, Swarm B, or Swarm C, respectively. If the product is derived from (available for) the satellite constellation (e.g. A and C) x = _. For more information see L2 Product Name Convention.

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Product Classification

AUX Products: These products are necessary prior or during processing of high precision Swarm L2 products (see L2 Product Definitions) but do not result from the Swarm L0 or L1b processor. Auxiliary products are further classified in auxiliary models and auxiliary data. For auxiliary products that are needed in Cat-1 as well as in Cat-2 chains (see Product Classification), two different products are defined. The name of all Cat-2 auxiliary products end with the letter F – Fast track (see Product Classification).

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Auxiliary Products

Complete information about the auxiliary products can be found in the following document: "Product specification for L2 Products and Auxiliary Products".

⇒ AUX_OBS_2_
Product identifier AUX_OBS_2_
Definition Geomagnetic Observatory Data are hourly means of the three components of the Earth's magnetic field measured at magnetic observatories, in geocentric (North-East-Centred) coordinates. More details on data processing can be found in [RD-20].
Application Comprehensive Inversion chain products, MIO_SHAi2D, MMA_SHA_2F, MCO_VAL_2_, MIO_VAL_2_
Spatial representation Values at about one hundred magnetic observatories at the Earth's surface
Time representation Time series (1 hour averages)
Units nT
Resolution 0.1nT
Quality indicator The ‘Quality' channel identifies data as INTERMAGNET ‘Quasi-definitive' (available within three months) or ‘Definitive' (available after about one year). See intermagnet.org for details.
Data volume < 150Mb/yr
Data format ASCII listing (others)
Example:
#Observatory hourly mean values selected from WDC Edinburgh/INTERMAGNET
#File created on   6  2 2012
#obs  gc_lat    long      rad yyyy mm dd  UT N=-Btheta   E=Bphi    C=-Br
########################################################################
#AAE1
AAE1   8.974  38.767 6380.055 1998  1  1  0.5  35961.0      NaN    968.0
AAE1   8.974  38.767 6380.055 1998  1  1  1.5  35960.0    746.0    968.0
....
AAE1   8.974  38.767 6380.055 1998 12 31 22.5  35987.0    758.0   1036.0
AAE1   8.974  38.767 6380.055 1998 12 31 23.5  35988.0    756.0   1036.0
#ABK0
ABK0  68.218  18.817 6360.064 1998  1  1  0.5  11466.0    966.0  51282.0
ABK0  68.218  18.817 6360.064 1998  1  1  1.5  11467.0    965.0  51281.0
....

Format description:

Variable number of header lines each starting with ‘#'. Note,
embedded header lines expected, such as introducing a next station
(see example above)

Missing value flag = NaN

Column  Format  Description
======  ======  ===========
 1-4     s4     3-letter IAGA code, followed by digit
 5-12    f8.3   geocentric latitude (degrees)
13-20    f8.3   geocentric longitude (degrees)
21-39    f9.3   radius (km)
30-34    i5     year
35-37    i3     month
38-40    i3     day
41-45    f5.1   UT (hours)
46-54    f9.1   North (-B_theta) component (nT)
55-63    f9.1   East (B_phi) component (nT)
64-72    f9.1   Centered (-B_r) component (nT)
Update rate Every 3 months
Latency 3 months for quasi-definitive – 1-2 years for definitive
Availability BGS: ftp://ftp.nerc-murchison.ac.uk/geomag/Swarm/AUX_OBS/
Notes  

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⇒ AUX_OBSM2_
Product identifier AUX_OBSM2_
Definition Geomagnetic Observatory Data are 1 minute means of the three components of the Earth's magnetic field measured at magnetic observatories, in geocentric (North-East-Centred) coordinates.
Application Comprehensive Inversion chain products, MIO_SHAi2D, MMA_SHA_2F, MCO_VAL_2_, MIO_VAL_2_
Spatial representation Values at about one hundred magnetic observatories at the Earth's surface
Time representation Time series (1 minute averages)
Units nT
Resolution 0.1nT
Quality indicator The ‘Quality' channel identifies data as INTERMAGNET ‘Quasi-definitive' (available within three months) or ‘Definitive' (available after about one year). See intermagnet.org for details.
Data volume < 3Mb/day
Data format CDF
Field name Type Unit Contents
IAGA_code CDF_CHAR - IAGA three letter observatory identification code associated with datum
Quality CDF_CHAR - Data quality: D for definitive and Q for quasi-definitive
Timestamp CDF_EPOCH - Date and time
Longitude CDF_DOUBLE deg Longitude
Latitude CDF_DOUBLE deg Geocentric latitude
Radius CDF_DOUBLE m Radius
B_NEC CDF_DOUBLE nT Geocentric-north, east, and geocentric-down component of magnetic field. NaN values are used as placeholders for missing data
Update rate Daily
Latency 4-days, 1-, 3-, 6-months, 1-, 2- and 4-years
Availability BGS: ftp://ftp.nerc-murchison.ac.uk/geomag/Swarm/AUX_OBS/
Notes  

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⇒ AUX_OBSS2_
Product identifier AUX_OBSS2_
Definition Geomagnetic Observatory Data are 1 second values of the three components of the Earth's magnetic field measured at magnetic observatories, in geocentric (North-East-Centred) coordinates.
Application Comprehensive Inversion chain products, MIO_SHAi2D, MMA_SHA_2F, MCO_VAL_2_, MIO_VAL_2_
Spatial representation Values at about one hundred magnetic observatories at the Earth's surface
Time representation Time series (1 second values)
Units nT
Resolution 0.01nT
Quality indicator The ‘Quality' channel identifies data as INTERMAGNET ‘Quasi-definitive' (available within three months) or ‘Definitive' (available after about one year). See intermagnet.org for details.
Data volume < 50Mb/day
Data format CDF
Field name Type Unit Contents
IAGA_code CDF_CHAR - IAGA three letter observatory identification code associated with datum
Quality CDF_CHAR - Data quality: D for definitive and Q for quasi-definitive
Timestamp CDF_EPOCH - Date and time
Longitude CDF_DOUBLE deg Longitude
Latitude CDF_DOUBLE deg Geocentric latitude
Radius CDF_DOUBLE m Radius
B_NEC CDF_DOUBLE nT Geocentric-north, east, and geocentric-down component of magnetic field. NaN values are used as placeholders for missing data
Update rate Daily
Latency 4-days, 1-, 3-, 6-months, 1-, 2- and 4-years
Availability BGS: ftp://ftp.nerc-murchison.ac.uk/geomag/Swarm/AUX_OBS/
Notes  

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