Table 3 Quasi-definitive observatories used for calibration model, including estimated crustal biases which are given in units of nT
From: Investigation of geomagnetic reference models based on the Iridium\(^{\circledR }\) constellation
IAGA code | Name | Country | Colatitude (\(^{\circ }\)) | East longitude (\(^{\circ }\)) | Bias\(B_r\) | Bias\(B_{\theta }\) | Bias\(B_{\phi }\) | Data start | Data end |
|---|---|---|---|---|---|---|---|---|---|
ABK | Abisko | Sweden | 21.642 | 18.823 | − 28.3 | − 21.2 | 57.5 | 1 Jan 1998 | 31 Jul 2020 |
ASC | Ascension Island | United Kingdom | 97.95 | 345.62 | − 25.8 | 497.7 | 269.4 | 1 Jan 1998 | 21 Jul 2020 |
ASP | Alice Springs | Australia | 113.77 | 133.88 | − 40.6 | − 53.2 | − 19.2 | 1 Jan 1998 | 30 Jun 2020 |
BEL | Belsk | Poland | 38.164 | 20.789 | − 311.7 | − 127.0 | 135.3 | 1 Jan 1998 | 30 Jun 2020 |
BOU | Boulder | United States of America | 49.86 | 254.76 | 139.2 | − 0.9 | 37.6 | 1 Jan 1998 | 30 Jun 2020 |
BOX | Borok | Russia | 31.93 | 38.23 | 349.8 | − 2.6 | 1.8 | 1 Jan 1998 | 30 Apr 2020 |
BRW | Barrow | United States of America | 18.68 | 203.38 | 53.0 | − 34.9 | − 67.0 | 2 Jan 1998 | 30 Jun 2020 |
CKI | Cocos-Keeling Islands | Australia | 102.1875 | 96.8336 | 169.6 | 259.2 | − 97.2 | 1 Jan 2013 | 30 Jun 2020 |
CLF | Chambon la Foret | France | 41.98 | 2.27 | − 107.0 | 65.7 | − 16.0 | 1 Jan 1998 | 30 Apr 2020 |
CMO | College | United States of America | 25.13 | 212.14 | 11.9 | − 17.4 | 8.5 | 1 Jan 1998 | 30 Jun 2020 |
CNB | Canberra | Australia | 125.32 | 149.36 | − 78.7 | − 3.8 | 49.0 | 1 Jan 1998 | 30 Jun 2020 |
CSY | Casey Station | Antarctica | 156.283 | 110.533 | 408.1 | − 720.1 | − 169.5 | 1 Jan 2011 | 31 May 2020 |
CTA | Charters Towers | Australia | 110.1 | 146.3 | − 176.1 | 437.6 | − 83.9 | 1 Jan 1998 | 30 Jun 2020 |
CYG | Cheongyang | Republic of Korea | 53.63 | 126.854 | 97.2 | 50.1 | 52.7 | 1 Jan 2014 | 14 Dec 2019 |
DLT | Dalat | Vietnam | 78.06 | 108.48 | − 137.6 | 56.5 | − 44.8 | 20 Apr 2011 | 28 Dec 2019 |
DOU | Dourbes | Belgium | 39.9 | 4.6 | − 77.5 | − 25.3 | − 18.0 | 1 Jan 1998 | 31 May 2020 |
EBR | Ebro | Spain | 49.043 | 0.333 | − 4.9 | 1.5 | 5.4 | 1 Jan 1998 | 31 May 2020 |
ESK | Eskdalemuir | United Kingdom | 34.68 | 356.8 | 60.1 | − 20.2 | − 34.6 | 1 Jan 1998 | 21 Jul 2020 |
FRD | Fredericksburg | United States of America | 51.8 | 282.63 | − 110.6 | − 83.2 | − 44.4 | 1 Jan 1998 | 30 Jun 2020 |
FRN | Fresno | United States of America | 52.91 | 240.28 | 235.7 | − 5.4 | − 16.9 | 1 Jan 1998 | 30 Jun 2020 |
GNG | Gingin | Australia | 121.356 | 115.715 | − 164.8 | − 0.9 | − 38.5 | 1 Jan 2012 | 30 Jun 2020 |
GUA | Guam | United States of America | 76.41 | 144.87 | − 54.2 | − 126.1 | 78.9 | 2 Jan 1998 | 30 Jun 2020 |
HAD | Hartland | United Kingdom | 39 | 355.52 | − 67.5 | 31.7 | 14.6 | 1 Jan 1998 | 21 Jul 2020 |
HER | Hermanus | South Africa | 124.43 | 19.23 | − 26.3 | − 29.5 | 7.3 | 1 Jan 1998 | 31 Jul 2020 |
HON | Honolulu | United States of America | 68.68 | 202.0 | 324.2 | 162.0 | 88.8 | 1 Jan 1998 | 3 Feb 2020 |
HRN | Hornsund | Norway | 12.998 | 15.547 | 44.3 | 30.5 | − 49.1 | 1 Jan 1998 | 30 Jun 2020 |
HYB | Hyderabad | India | 72.6 | 78.6 | − 468.3 | − 270.5 | 26.8 | 1 Jan 2009 | 6 Jul 2020 |
JCO | Jim Carrigan Observatory | United States of America | 19.644 | 211.201 | 49.5 | 13.2 | − 40.9 | 1 Jan 2005 | 21 Jul 2020 |
KAK | Kakioka | Japan | 53.77 | 140.18 | 98.0 | − 14.3 | 14.4 | 1 Jan 1998 | 31 May 2020 |
KDU | Kakadu | Australia | 102.69 | 132.47 | − 20.8 | − 11.3 | − 33.0 | 1 May 1998 | 30 Jun 2020 |
KEP | King Edward Point | South Georgia and the South Sandwich Islands | 144.2821 | 323.5071 | − 86.6 | 26.6 | − 44.2 | 25 Feb 2011 | 21 Jul 2020 |
KHB | Khabarovsk | Russia | 42.39 | 134.69 | − 606.8 | 281.0 | − 429.3 | 1 Jan 2012 | 23 Jul 2020 |
KNY | Kanoya | Japan | 58.58 | 130.88 | 39.4 | − 4.4 | 52.4 | 1 Jan 1998 | 31 May 2020 |
KOU | Kourou | French Guiana | 84.79 | 307.27 | 39.7 | − 112.6 | 99.8 | 12 Jan 1998 | 30 Apr 2020 |
LER | Lerwick | United Kingdom | 29.87 | 358.82 | − 40.1 | 126.2 | 175.9 | 1 Jan 1998 | 21 Jul 2020 |
LRM | Learmonth | Australia | 112.22 | 114.1 | − 173.7 | 28.8 | − 33.0 | 1 Jan 1998 | 30 Jun 2020 |
LYC | Lycksele | Sweden | 25.4 | 18.8 | 212.9 | − 134.6 | − 34.6 | 1 Jan 2008 | 31 Jul 2020 |
MAW | Mawson | Antarctica | 157.6 | 62.88 | − 184.7 | − 44.1 | 6.3 | 1 Jan 1998 | 30 Jun 2020 |
MCQ | Macquarie Island | Australia | 144.5 | 158.95 | − 291.4 | − 278.4 | − 2.6 | 1 Jan 1998 | 30 Jun 2020 |
MGD | Magadan | Russia | 29.949 | 150.728 | − 44.6 | 251.1 | − 718.4 | 1 Jan 2012 | 12 Jul 2020 |
MMB | Memambetsu | Japan | 46.09 | 144.19 | − 47.1 | 207.2 | 144.4 | 1 Jan 1998 | 31 May 2020 |
NAQ | Narsarsuaq | Greenland | 28.84 | 314.558 | − 466.1 | 288.8 | 266.5 | 1 Jan 1998 | 31 May 2020 |
NEW | Newport | United States of America | 41.73 | 242.88 | 125.2 | 20.5 | 114.9 | 1 Jan 1998 | 30 Jun 2020 |
NGK | Niemegk | Germany | 37.93 | 12.68 | 78.1 | 12.3 | − 0.8 | 1 Jan 1998 | 30 Jul 2020 |
NVS | Novosibirsk | Russia | 35.15 | 83.23 | − 18.7 | − 77.6 | − 55.1 | 1 Jan 1998 | 26 Jul 2020 |
PET | Paratunka | Russia | 37.029 | 158.248 | − 134.4 | 293.3 | 251.8 | 1 Jan 1998 | 25 Jul 2020 |
PST | Port Stanley | Falkland Islands | 141.7 | 302.11 | − 32.3 | − 36.1 | − 11.5 | 7 Sep 2005 | 21 Jul 2020 |
SBL | Sable Island | Canada | 46.0679 | 299.9905 | 88.6 | − 11.5 | 9.3 | 1 Jan 2000 | 21 Jul 2020 |
SFS | San Fernando | Spain | 53.333 | 354.055 | − 153.0 | 93.4 | 31.9 | 1 Jan 1998 | 30 Jul 2020 |
SHU | Shumagin | United States of America | 34.65 | 199.54 | − 29.5 | − 415.9 | − 234.4 | 1 Jan 2005 | 25 Jun 2020 |
SIT | Sitka | United States of America | 32.94 | 224.67 | 85.6 | − 27.2 | − 16.0 | 1 Jan 1998 | 30 Jun 2020 |
SJG | San Juan | United States of America | 71.89 | 293.85 | − 127.2 | 51.6 | 131.3 | 1 Jan 1998 | 30 Jun 2020 |
SPT | San Pablo-Toledo | Spain | 50.45 | 355.65 | 26.9 | − 13.7 | 9.1 | 1 Jan 1998 | 31 May 2020 |
TAM | Tamanrasset | Algeria | 67.21 | 5.53 | 59.0 | − 56.5 | − 218.8 | 1 Jan 1998 | 30 Apr 2020 |
THY | Tihany | Hungary | 43.1 | 17.89 | 57.3 | 5.5 | − 12.9 | 1 Jan 1999 | 31 Dec 2018 |
TUC | Tucson | United States of America | 57.82 | 249.27 | − 419.5 | 82.0 | − 265.2 | 1 Jan 1998 | 30 Jun 2020 |
UPS | Uppsala | Sweden | 30.097 | 17.353 | 119.9 | − 151.9 | − 14.5 | 1 Jan 2003 | 31 Jul 2020 |
WIC | Conrad Observatory | Austria | 42.0695 | 15.8657 | 18.3 | − 14.9 | − 2.5 | 1 Jan 2015 | 24 Jul 2020 |
WNG | Wingst | Germany | 36.26 | 9.07 | 73.4 | − 68.0 | 49.0 | 1 Jan 1998 | 30 Jul 2020 |