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Space Science Reviews

, Volume 206, Issue 1–4, pp 91–122 | Cite as

The Mid-Latitude Positive Bay and the MPB Index of Substorm Activity

  • Robert L. McPherron
  • Xiangning Chu
Article

Abstract

Substorms are a major source of magnetic activity. At substorm expansion phase onset a westward current flows through the expanding aurora. This current is the ionospheric closure of the substorm current wedge produced by diversion of tail current along magnetic field lines. At low latitudes the field-aligned currents create a systematic pattern in the north (X) and east (Y) components of the surface magnetic field. The rise and decay in X is called a midlatitude positive bay whose start is a proxy for expansion onset. In this paper we describe a new index called the midlatitude positive bay index (MPB) which monitors the power in the substorm perturbations of X and Y. The index is obtained by removing the main field, storm time variations, and the solar quiet (Sq) variation from the measured field. These are estimated with spline fits and principal component analysis. The residuals of X and Y are high pass filtered to eliminate variations with period longer than 3 hours. The sum of squares of the X and Y power is determined at each of 35 midlatitude stations. The average power in night time stations is the MPB index. The index series is standardized and intervals above a fixed threshold are taken as possible bay signatures. Post processing constrains these to have reasonable values of rise time, strength, and duration. Minima in the index before and after the peak are taken as the start and end of the bay. The MPB and AL indices can be used to identify quiet intervals in the magnetic field.

Keywords

Substorm Substorm current wedge Field-aligned current Quiet day variation Midlatitude positive bay index (MPB) MPB onsets 

Notes

Acknowledgements

The principal author is grateful to the International Space Science Institute (ISSI) for inviting him to take part in the Workshop on “Earth’s Magnetic Field” held in Bern in May 2015. This work was supported by ISSI, NSF GEM 1003854, and NASA NESSF NNX14AO02H. We gratefully acknowledge THEMIS (themis. ssl.berkeley.edu), INTERMAGNET (www.intermagnet.org), GOES, OMNI database (omniweb.gsfc.nasa.gov), SuperMAG (supermag.jhuapl.edu), and their data providers. The authors would also like to thank the NASA NSSDC and NASA VMO centers.

Supplementary material

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References

  1. S.I. Akasofu, S. Chapman, On the asymmetric development of magnetic storm fields in low and middle latitudes. Planet. Space Sci. 12(6), 607–626 (1964). doi: 10.1016/0032-0633(64)90008-X ADSCrossRefGoogle Scholar
  2. S.I. Akasofu, C.I. Meng, A study of polar magnetic substorms. J. Geophys. Res. 74(1), 293–313 (1969). doi: 10.1029/JA074i001p00293 ADSCrossRefGoogle Scholar
  3. S.I. Akasofu, S. Chapman, J.C. Cain, Magnetic field of a model radiation belt numerically computed. J. Geophys. Res. 66(12), 4013 (1961). doi: 10.1029/JZ066i012p04013 ADSCrossRefGoogle Scholar
  4. S.-I. Akasofu, S. Chapman, C.-I. Meng, The polar electrojet. J. Atmos. Terr. Phys. 27(11–12), 1275–1305 (1965). doi: 10.1016/0021-9169(65)90087-5 ADSCrossRefGoogle Scholar
  5. D.R. Barraclough, T.D.G. Clark, S.W.H. Cowley, F.H. Hibberd, R. Hide, D.J. Kerridge, F.J. Lowes, S.R.C. Malin, T. Murphy, H. Rishbeth, S.K. Runcorn, H.C. Soffel, D.N. Stewart, W.F. Stuart, K.A. Whaler, D.E. Winch, 150 years of magnetic observatories: recent researches on world data. Surv. Geophys. 13(1), 47–88 (1992). doi: 10.1007/BF01901951 ADSCrossRefGoogle Scholar
  6. D.R. Brillinger, Measuring association of point processes – case history. Am. Math. Mon. 83(1), 16–22 (1976). doi: 10.2307/2318824 MathSciNetCrossRefMATHGoogle Scholar
  7. M. Caan, R. McPherron, C. Russell, Substorm and interplanetary magnetic field effects on the geomagnetic tail lobes. J. Geophys. Res. 80(1), 191–194 (1975). doi: 10.1029/JA080i001p00191 ADSCrossRefGoogle Scholar
  8. M.N. Caan, R.L. McPherron, C.T. Russell, The statistical magnetic signature of magnetospheric substorms. Planet. Space Sci. 26(3), 269–279 (1978) ADSCrossRefGoogle Scholar
  9. S. Chapman, J. Bartels, Geomagnetism, 2nd edn., vol. 1 (Clarendon, Oxford, 1962) Google Scholar
  10. S. Chapman, V.C.A. Ferraro, A new theory of magnetic storms. Terr. Magn. Atmos. Electr. 36(3), 171–186 (1931). doi: 10.1029/TE036i003p00171 CrossRefMATHGoogle Scholar
  11. X. Chu, Configuration and Generation of Substorm Current Wedge (University of California Los Angeles, Los Angeles, 2015) Google Scholar
  12. X.N. Chu, T.S. Hsu, R.L. McPherron, V. Angelopoulos, Z.Y. Pu, J.J. Weygand, K. Khurana, M. Connors, J. Kissinger, H. Zhang, O. Amm, Development and validation of inversion technique for substorm current wedge using ground magnetic field data. J. Geophys. Res. Space Phys. 119(3), 1909–1924 (2014). doi: 10.1002/2013ja019185 ADSCrossRefGoogle Scholar
  13. X. Chu, R.L. McPherron, T.-S. Hsu, V. Angelopoulos, Solar cycle dependence of substorm occurrence and duration: implications for onset. J. Geophys. Res. Space Phys. 120(4), 2808–2818 (2015). doi: 10.1002/2015ja021104 ADSCrossRefGoogle Scholar
  14. C. Clauer, Y. Kamide, DP 1 and DP 2 current systems for the March 22, 1979 substorms. J. Geophys. Res. 90(A2), 1343–1354 (1985). doi: 10.1029/JA090iA02p01343 ADSCrossRefGoogle Scholar
  15. C. Clauer, R. McPherron, Mapping the local time-universal time development of magnetospheric substorms using mid-latitude magnetic observations. J. Geophys. Res. 79(19), 2811–2820 (1974a). doi: 10.1029/JA079i019p02811 ADSCrossRefGoogle Scholar
  16. C. Clauer, R. McPherron, Variability of mid-latitude magnetic parameters used to characterize magnetospheric substorms. J. Geophys. Res. 79(19), 2898–2900 (1974b). doi: 10.1029/JA079i019p02898 ADSCrossRefGoogle Scholar
  17. C.R. Clauer, R.L. McPherron, The relative importance of the interplanetary electric field and magnetospheric substorms on partial ring current development. J. Geophys. Res. 85, (A12):6747–6759 (1980). doi: 10.1029/JA085iA12p06747 ADSGoogle Scholar
  18. F. Coroniti, R. McPherron, G. Parks, Studies of the magnetospheric substorm, 3: concept of the magnetospheric substorm and its relation to electron precipitation and micropulsations. J. Geophys. Res. 73(5), 1715–1722 (1968). doi: 10.1029/JA073i005p01715 ADSCrossRefGoogle Scholar
  19. S.W.H. Cowley, Magnetosphere-ionosphere interactions: a tutorial review, in Magnetospheric Current Systems. Geophys. Monogr. Ser., vol. 118 (AGU, Washington, 2000), pp. 91–106. doi: 10.1029/GM118p0091 CrossRefGoogle Scholar
  20. W.D. Cummings, Asymmetric ring currents and the low-latitude disturbance daily variation. J. Geophys. Res. 71(19), 4495–4503 (1966) ADSCrossRefGoogle Scholar
  21. T. Davis, M. Sugiura, Auroral electrojet activity index AE and its universal time variations. J. Geophys. Res. 71(3), 785–801 (1966). doi: 10.1029/JZ071i003p00785 ADSCrossRefGoogle Scholar
  22. H.U. Frey, S.B. Mende, V. Angelopoulos, E.F. Donovan, Substorm onset observations by IMAGE-FUV. J. Geophys. Res. 109(A10), 1–6 (2004). doi: 10.1029/2004JA010607 Google Scholar
  23. V.P. Golovkov, N.E. Papitashvili, Y.S. Tyupkin, E.P. Kharin, Separation of geomagnetic field variations into quiet and disturbed components by the method of natural orthogonal components. Geomagn. Aeron. 18(3), 342–344 (1978) Google Scholar
  24. B. Horning, R. McPherron, D. Jackson, Application of linear inverse theory to a line current model of substorm current systems. J. Geophys. Res. 79(34), 5202–5210 (1974). doi: 10.1029/JA079i034p05202 ADSCrossRefGoogle Scholar
  25. T. Iijima, T. Potemra, The amplitude distribution of field-aligned currents at northern high latitudes observed by triad. J. Geophys. Res. 81(13), 2165–2174 (1976a). doi: 10.1029/JA081i013p02165 ADSCrossRefGoogle Scholar
  26. T. Iijima, T. Potemra, Field-aligned currents in the dayside cusp observed by triad. J. Geophys. Res. 81(34), 5971–5979 (1976b). doi: 10.1029/JA081i034p05971 ADSCrossRefGoogle Scholar
  27. T. Iijima, T.A. Potemra, Large-scale characteristics of field-aligned currents associated with substorms. J. Geophys. Res. Space Phys. 83(A2), 599–615 (1978). doi: 10.1029/JA083iA02p00599 ADSCrossRefGoogle Scholar
  28. T. Iyemori, T. Araki, T. Kamei, M. Takeda, Mid-Latitude Geomagnetic Indices ASY and SYM (Provisional). (Kyoto University, Kyoto, 1994) Google Scholar
  29. K. Kauristie, A. Morschhauser, N. Olsen, C. Finlay, R.L. McPherron, J.W. Gjerloev, H.J. Opgenoorth, How geomagnetic indices can help in internal field modelling. Space Sci. Rev. (2016). doi: 10.1007/s11214-016-0301-0 Google Scholar
  30. L. Kepko, R.L. McPherron, O. Amm, S. Apatenkov, W. Baumjohann, J. Birn, M. Lester, R. Nakamura, T.I. Pulkkinen, V. Sergeev, Substorm current wedge revisited. Space Sci. Rev. 190, 1–46 (2014a). doi: 10.1007/s11214-014-0124-9 ADSCrossRefGoogle Scholar
  31. L. Kepko, R.L. McPherron, O. Amm, S. Apatenkov, W. Baumjohann, J. Birn, M. Lester, R. Nakamura, T.I. Pulkkinen, V. Sergeev, Substorm current wedge revisited. Space Sci. Rev. 190(1–4), 1–46 (2014b). doi: 10.1007/s11214-014-0124-9 ADSGoogle Scholar
  32. M.G. Kivelson, C.T. Russell (eds.), Introduction to Space Physics (Cambridge Univ. Press, Cambridge, 1995) Google Scholar
  33. G. Le, J.A. Slavin, R.J. Strangeway, Space Technology 5 observations of the imbalance of regions 1 and 2 field-aligned currents and its implication to the cross-polar cap Pedersen currents. J. Geophys. Res. Space Phys. 115(A7), A07202 (2010). doi: 10.1029/2009JA014979 ADSCrossRefGoogle Scholar
  34. P.N. Mayaud, Derivation, Meaning and Use of Geomagnetic Indices, vol. 22 (American Geophysical Union, Washington, 1980). doi: 10.1029/GM022 CrossRefGoogle Scholar
  35. R.L. McPherron, Substorm related changes in the geomagnetic tail: the growth phase. Planet. Space Sci. 20(9), 1521–1539 (1972) ADSCrossRefGoogle Scholar
  36. R.L. McPherron, The EARTH: its properties, composition and structure, in Encyclopedia Britannica (1987), pp. 545–558 Google Scholar
  37. R.L. McPherron, Earth’s magnetotail, in Magnetotails in the Solar System (Wiley, New York, 2015), pp. 61–84. doi: 10.1002/9781118842324.ch4 Google Scholar
  38. R. McPherron, C. Russell, M. Aubry, Phenomenological model for substorms. J. Geophys. Res. 78(16), 3131–3149 (1973a). doi: 10.1029/JA078i016p03131 ADSCrossRefGoogle Scholar
  39. R.L. McPherron, C.T. Russell, M. Aubry, Satellite studies of magnetospheric substorms on August 15, 1968, 9: phenomenological model for substorms. J. Geophys. Res. 78(16), 3131–3149 (1973b) ADSCrossRefGoogle Scholar
  40. R.L. McPherron, T.S. Hsu, J. Kissinger, X. Chu, V. Angelopoulos, Characteristics of plasma flows at the inner edge of the plasma sheet. J. Geophys. Res. Space Phys. 116, A00I33 (2011). doi: 10.1029/2010ja015923 ADSCrossRefGoogle Scholar
  41. G.D. Mead, Deformation of the geomagnetic field by the solar wind. J. Geophys. Res. 69(7), 1181–1195 (1964). doi: 10.1029/JZ069i007p01181 ADSCrossRefMATHGoogle Scholar
  42. R.T. Merrill, P.L. McFadden, Geomagnetic polarity transitions. Rev. Geophys. 37(2), 201–226 (1999). doi: 10.1029/1998rg900004 ADSCrossRefGoogle Scholar
  43. T. Nagai, R. Nakamura, T. Mukai, T. Yamamoto, A. Nishida, S. Kokubun, Substorms, tail flows and plasmoids. Adv. Space Res. 20(4–5), 961–971 (1997). doi: 10.1016/s0273-1177(97)00504-8 ADSCrossRefGoogle Scholar
  44. P.T. Newell, J.W. Gjerloev, Evaluation of SuperMAG auroral electrojet indices as indicators of substorms and auroral power. J. Geophys. Res. Space Phys. 116, A12211 (2011). doi: 10.1029/2011ja016779 ADSCrossRefGoogle Scholar
  45. A. Nishida, DP 2 and polar substorm. Planet. Space Sci. 19(2), 205–221 (1971) ADSCrossRefGoogle Scholar
  46. W.H. Press, B.P. Flannery, S.A. Teukolsky, W.T. Vettering, Numerical Recipes (Cambridge Univ. Press, New York, 1986) MATHGoogle Scholar
  47. V.A. Sergeev, N.A. Tsyganenko, M.V. Smirnov, A.V. Nikolaev, H.J. Singer, W. Baumjohann, Magnetic effects of the substorm current wedge in a “spread-out wire” model and their comparison with ground, geosynchronous, and tail lobe data. J. Geophys. Res. Space Phys. 116, A07218 (2011). doi: 10.1029/2011ja016471 ADSCrossRefGoogle Scholar
  48. J.A. Slavin, M.F. Smith, E.L. Mazur, D.N. Baker, T. Iyemori, H.J. Singer, E.W. Greenstadt, ISEE 3 plasmoid and TCR observations during an extended interval of substorm activity. Geophys. Res. Lett. 19(8), 825–828 (1992). doi: 10.1029/92gl00394 ADSCrossRefGoogle Scholar
  49. P. Stauning, The polar cap index: a critical review of methods and a new approach. J. Geophys. Res. Space Phys. 118(8), 5021–5038 (2013). doi: 10.1002/jgra.50462 ADSCrossRefGoogle Scholar
  50. M. Sugiura, T. Kamei, Equatorial Dst Index 1957–1986 (ISGI Publications Office, Saint-Maur-des-Fosses, 1991) Google Scholar
  51. O. Troshichev, V.G. Andrezen, S. Vennerstrøm, E. Friis-Christensen, Relationship between the polar cap activity index PC and the auroral zone indices AU, AL, AE. Planet. Space Sci. 36, 1095 (1988) ADSCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2016

Authors and Affiliations

  1. 1.Department of Earth, Planetary, and Space SciencesUniversity of California Los AngelesLos AngelesUSA

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