基于MHD数值模拟的行星际激波传播与预报研究
摘要
在行星际空间中传播的大尺度激波结构有两种,一种与日冕物质抛射(Coronal Mass Ejections, CME)有关,是当CME的抛射速度超过在太阳风中传播的快磁声波波速时激发的；另一种与行星际共转相互作用区(Corotating Interaction Region, CIR)有关,主要由太阳自转所导致的基本沿径向传播的低、高速太阳风流的相互作用而形成。利用二维磁流体力学方程PPM数值计算格式,本文分别针对这两种激波在行星际空间的传播过程进行了计算。
对于由CME驱动的行星际激波,我们将不同参数条件下的大量数值计算得到的MHD激波参数解编制成数据库,并据此构建了可用于CME激波预报的ForSPA模式。利用该模式,给定初始激波强度和所在位置等输入参数后,便可方便地获取激波在0.1-1AU之间,在子午面和赤道面时空位置上的物理特征。我们应用该模式对2002年8月至2006年12月之间的68次激波事件进行了试预报,并与相应的观测结果和其他模式的预报结果作了比较,发现预报效果较好。
在对共转相互作用区及伴随激波的初步研究中,我们主要分析了形成作用区的快慢太阳风的速度对共转激波形成高度的影响。通过参数研究,我们发现：1、低速太阳风的速度不变,则高速太阳风速度的越高,共转激波的形成高度越低；2、高低速太阳风的速度比值不变,则高低速太阳风的速度取值越大,共转激波的形成高度越高。
In the interplanetary space, there exist two types of large-scale shock structures. One is driven by CMEs (Coronal Mass Ejections) with propagating speeds faster than that of the fast magnetosonic wave in the solar wind, the other results from the interaction between the approaching fast and slow solar winds flowing outwards along the same radial direction. Both of these two types of shocks are investigated numerically in this thesis by solving associated ideal magnetohydrodynamic (MHD) equations with the PPM (Piecewise Parabolic Method) scheme.
In the case of CME-driven shocks, we developed a space weather forecasting model, the ForSPA (Forecasting Model of interplanetary Shock PropAgation based on MHD simulation) model, making use of the obtained database of a large number of numerical solutions of CME-shocks propagating in both the solar meridian plane and the equatorial plane. The solutions are given by calculations with prescribed initial shock parameters including the shock strength and the shock location. With ForSPA, we are able to obtain numerical solutions of CME-shocks with freely-specified certain initial parameters, and to estimate the shock arrival time (SAT) as well as other concerned parameters at 1 AU or at the Earth. We then make tentative predictions on SATs for the 68 CME-shock events dated between August 2002 and December 2006, and compare with other contemporary forecasting models of CME-shocks. It is found that the statistical errors of SATs given by ForSPA predictions are in general no larger than that given by other models.
In the preliminary studies on the CIR (Corotating Interaction Regions) shocks, we focus on the effect of the solar wind speed on the formation heights of the shocks. Through two sets of parameter studies, we find that, (1) the formation heights decrease with a larger speed of the fast solar wind while the speed of the slow wind is fixed; (2) the formation heights increase with a larger solar wind speed while the speed ratio of the two wind components is fixed.
对于由CME驱动的行星际激波,我们将不同参数条件下的大量数值计算得到的MHD激波参数解编制成数据库,并据此构建了可用于CME激波预报的ForSPA模式。利用该模式,给定初始激波强度和所在位置等输入参数后,便可方便地获取激波在0.1-1AU之间,在子午面和赤道面时空位置上的物理特征。我们应用该模式对2002年8月至2006年12月之间的68次激波事件进行了试预报,并与相应的观测结果和其他模式的预报结果作了比较,发现预报效果较好。
在对共转相互作用区及伴随激波的初步研究中,我们主要分析了形成作用区的快慢太阳风的速度对共转激波形成高度的影响。通过参数研究,我们发现：1、低速太阳风的速度不变,则高速太阳风速度的越高,共转激波的形成高度越低；2、高低速太阳风的速度比值不变,则高低速太阳风的速度取值越大,共转激波的形成高度越高。
In the interplanetary space, there exist two types of large-scale shock structures. One is driven by CMEs (Coronal Mass Ejections) with propagating speeds faster than that of the fast magnetosonic wave in the solar wind, the other results from the interaction between the approaching fast and slow solar winds flowing outwards along the same radial direction. Both of these two types of shocks are investigated numerically in this thesis by solving associated ideal magnetohydrodynamic (MHD) equations with the PPM (Piecewise Parabolic Method) scheme.
In the case of CME-driven shocks, we developed a space weather forecasting model, the ForSPA (Forecasting Model of interplanetary Shock PropAgation based on MHD simulation) model, making use of the obtained database of a large number of numerical solutions of CME-shocks propagating in both the solar meridian plane and the equatorial plane. The solutions are given by calculations with prescribed initial shock parameters including the shock strength and the shock location. With ForSPA, we are able to obtain numerical solutions of CME-shocks with freely-specified certain initial parameters, and to estimate the shock arrival time (SAT) as well as other concerned parameters at 1 AU or at the Earth. We then make tentative predictions on SATs for the 68 CME-shock events dated between August 2002 and December 2006, and compare with other contemporary forecasting models of CME-shocks. It is found that the statistical errors of SATs given by ForSPA predictions are in general no larger than that given by other models.
In the preliminary studies on the CIR (Corotating Interaction Regions) shocks, we focus on the effect of the solar wind speed on the formation heights of the shocks. Through two sets of parameter studies, we find that, (1) the formation heights decrease with a larger speed of the fast solar wind while the speed of the slow wind is fixed; (2) the formation heights increase with a larger solar wind speed while the speed ratio of the two wind components is fixed.
引文
[1]Sibeck, D.G., Newell, P. T., Pressure-pulse driven surface waves at the magneto-pause: A rebuttal, J. Geophys. Res.,100,21773-21778,1995
[2]Russell, C. T., Zhou X. W., Chi P., et al., Sudden compression of the outer magnetosphere associated with an ionospheric mass ejection. Geophys. Res. Lett., 26:2343-2346,1999
[3]Wu, C. C, Shock wave interaction with the magnetopause, J. Geophys. Res.,105, 7533-7543,2000
[4]Liou, K., Wu, C. C, et al., Midday sub-auroral patchs (MSPs) associated with interplanetary shocks, Geophys. Res. Lett.,29,1771-1774,2002
[5]Takeuchi, T. et al., Geomagnetic negative sudden impulse:interplanetary causes and polarization distribution, J. Geophys. Res.,107,1096-1100,2002
[6]MikiC, Z., Lee, M. A., An Introduction to Theory and Models of CMEs, Shocks, and Solar Energetic Particles, Space. Sci. Rev,123,57-80,2006
[7]Reames, D. V. Acceleration of energetic particles by shock waves from large solar flares, Space Sci. Rev.90,413-491,1999
[8]Feynman, J., and Gabriel, S. B, On space weather consequences and predictions, J. Geophys. Res.105,10543-10564.2000
[9]T'oth, G, Sokolov, I. V., Gombosi,.T. I., Chesney, D. R., Clauer, C. R., De Zeeuw, D. L., et al., Space Weather Modeling Framework:A new tool for the space science community, J. Geophys. Res,110, Cite ID A12226, DOI 10.1029/2005JA011126,2005
[10]Hu, Y. Q., Anisotropic propagation of flare-induced shocks, Chinese Science Bulletin, 43,402-404,1998
[11]Fry, C.D., Dryer, M., Smith, Z., Sun, W., Deehr, C.S., and Akasofu, S.-I, Forecasting solar wind structures and shock arrival times using an ensemble of models, J. Geophys. Res.,108,1070,2003
[12]Dryer, M., Interplanetary shock waves generated by solar flares, Space Sci. Rev.15, 403-468,1974
[13]Dryer, M. and Smart D. F., Dynamical models of coronal transients and interplanetary disturbances, Adv. Space Res,4,291-301,1984
[14]Smart, D. F., Shea, M. A., W. R. Barron, and M. Dryer, A simplified technique for estimating the arrival time of solar flare-initiated shocks, in Proceedings of STIP Workshop on Solar/Interplanetary Intervals, August 4-6,1982, Maynooth, Ireland, edited by M. A. Shea et al.,139-156, Bookcrafters, Inc., Chelsea, Mich.,1984.
[15]Smart, D. F., Shea, M. A., Dryer, M., Quintana, A., Gentile, L. C., Bathhurst A. A., Estimating the arrival time of solar flare-initiated shocks by considering them to be blast waves riding over the solar wind, in Proceedings of the Symposium on Solar-Terrestrial Predictions, edited by P. Simon, G. R. Heckman, and M. A. Shea, 471-481, U.S. Govt. Print. Off., Washington. D. C.,1986.
[16]Smart, D. F., Shea, M. A., A simplified model for timing the arrival of solar-flare-initiated shocks, J. Geophys. Res.,90,183-190,1985..
[17]Lewis, D. and Dryer, M, NOAA/SEL Contract Report, to U.S. Air Weather Service,1987
[18]Dryer, M., Shea, M. A., Smart, D. F., Collard, H. R., Mihalov, J. D., Wolfe, J. H., Warwick, J. R., On the observation of a flare generated shock wave at 9.7 AU by Pioneer 10, J. Geophys. Res.,83,1165-1168,1978.
[19]Wu, S. T., Dryer, M., and Han, S. M., Non-planar MHD model for solar flare-generated disturbances in the heliospheric equatorial plane, Solar Phys,84, 395-418,1983.
[20]Smith, Z., Dryer, M., MHD study of temporal and spatial evolution of simulated interplanetary shocks in the ecliptic plane within 1 AU, Sol. Phys.,129,387-405, 1990.
[21]Smith, Z., Dryer, M., The Interplanetary Shock Propagation Model:A model for predicting solar-flare-caused geomagnetic sudden impulses based on the 21/2 D MHD numerical simulation results from the Interplanetary Global Model (2D IGM), NOAA Tech. Memo., ERL/SEL-89, July 1995.
[22]Feng, X. S., Zhao, X. H., A new prediction method for the arrival time of interplanetary shocks, Solar Physics,238,167-186,2006
[23]Wei, F. S., The blast wave propagating in a moving medium with variable density, Chinese J. Space Sci.2,63-72.,1982
[24]Wei, F. S., Yang, G, Zhang, G, in Chen Biao and C. de Jager (eds.), Proceedings of Kunming Workshop on Solar Physics and Interplanetary Traveling Phenomena, Science Press, Beijing,1.2,1043,1983
[25]Hakamada, K., Akasofu, S. I., Simulation of three-dimensional solar wind disturbances and resulting geomagnetic storms, Space Sci. Rev.,32,3-70,1982
[26]Akasofu, S. I., Predicting geomagnetic storms as a space weather project, in Geophysical Monograph Series, edited by P. Song, G. Siscoe, and H. Singer, AGU, Washington, D. C.,2001
[27]Arge, C. N., Pizzo, V. J., Improvement in the prediction of solar wind conditions using near-real time solar magnetic field updates, J. Geophys. Res.105,10465-10480,2000
[28]Fry, C. D., Sun, W., Deehr, C. S., Dryer. M., Smith, Z., Akasofu, S-I., Tokumaru, M., Kojima, M., Improvements to the HAF solar wind model for space weather predictions, J. Geophys. Res.,106,20 985-21001,2001.
[29]McKenna-Lawlor, S. M. P., Dryer, M., Kartalev, M. D., Smith, Z., Fry, C. D., Sun, W., Deehr, C. S., Kecskemety, K., Kudela, K., Near real-time predictions of the arrival at Earth of flare-related shocks during Solar Cycle 23, J. Geophys. Res,111, A11103, doi:10.1029/2005JA011162.2006
[30]Smith, Z. K., Dryer, M., McKenna-Lawlor, S. M P., Fry, C. D., Deehr, C. S., Sun, W., Operational validation of HAFv2's predictions of interplanetary shock arrivals at Earth: Declining phase of Solar Cycle 23, J. Geophys. Res,114, A05106, doi:10.1029/2008JA013836,2009
[31]Reedy, R. C., Constraints on solar particle events from comparisons of recent events and million-years averages, Solar drivers of interplanetary and terrestrial disturbances ASP conference series,95,1996
[32]Smart, D., Shea, M., PPS73-A computerized'Event Mode'solor proton forecasting technique. Solar-Terrestrial Predictiions Proceeding of a Workshop, Boulder, US A,1,406-427,1979
[33]Feynman, J., Spitale, G., Wang, J. et al., Interplanetary proton fluence model-JPL 1991, J. Geophys. Res.98, A8,13281-13294,1993.
[34]Nymmik R. A., Radiation environment induced by cosmic ray particle fluxes in the international space station orbit according to recent galactic and solar cosmic ray models, Adv. Space Research 21 n.12,1689-1698,1998
[35]Aran A., Sanahuja, B., Lario, D., in'Solar Encounter:Proceedings of the First Solar Orbiter Workshop', p.157, Eds. B. Battrick & H. Sawaya-Lacoste,2001
[36]Aran, A., Sanahuja, B., Lario, D. A first step towards proton flux forecasting, Adv. Space Res.,36,2333-2338,2005
[37]Aran, A., Sanahuja, B., Lario, D., SOLPENCO:A solar particle engineering code, Adv. Space Res,37,1240-1246,2006
[38]Sanahuja, B., Aran, A., Lario, D., An engineering model for solar energetic particles in interplanetary space, ESA/ESTEC, December 2003
[39]Lario D., Sanahuja, B., Heras, A., M., Energetic particle events:efficiency of interplanetary shocks as 50kev [40]Ruffolo, D., Effect of adiabatic deceleration on the focused transport of solar cosmic rays, Astrophysical J,442,861-874,1995
[41]Pizzo, V. J., A Three-Dimensional Model of Corotating Streams in the Solar Wind-Ⅰ. Theoretical Foundations, J. Geophys. Res.83,5,563-5,572,1978
[42]涂传饴等,日地空间物理,P177,科学出版社,1988
[43]Smith, E. J., Wolfre, J. H., Pioneer-10,11 observations of evolving solar wind streams and shocks beyond 1AU, Study of traveling interplanetary phenomena, P227. Shea, M. A., Smart, D. F, Wu, S. T., (eds), D. Reidel Pub. Co., Dordrecht-Holland/Boston-USA, 1977
[44]Collela, P., Woodward, P. R., The piecewise parabolic method (PPM) for gas-dynamical simulations, J. comput. Phys.,54,174-201,1984
[45]Dai, W., Woodward, P. R., A simple Riemann solver and high-order Godunov schemes for hyperbolic systems of conservation laws, J. comput. Phys.,121,51-65,1995
[46]Webber, E. J., Davis, L Jr, The angular momentum of the solar wind, Astrophys. J,148, 217-228,1967
[47]Smith, Z. K., Dryer, M., McKenna-Lawlor, S. M. P., Fry, C. D., Deehr, C. S., Sun, W, Operational validation of HAFv2's predictions of interplanetary shock arrivals at Earth: Dec.lining phase of Solar Cycle 23, J. Geophys. Res,114, A05106, doi:10.1029/2008JA013836,2009
[48]Boyd, T. J. M., Sanderson, J. J., The physics of plasma, Cambridge university press, 2003
[2]Russell, C. T., Zhou X. W., Chi P., et al., Sudden compression of the outer magnetosphere associated with an ionospheric mass ejection. Geophys. Res. Lett., 26:2343-2346,1999
[3]Wu, C. C, Shock wave interaction with the magnetopause, J. Geophys. Res.,105, 7533-7543,2000
[4]Liou, K., Wu, C. C, et al., Midday sub-auroral patchs (MSPs) associated with interplanetary shocks, Geophys. Res. Lett.,29,1771-1774,2002
[5]Takeuchi, T. et al., Geomagnetic negative sudden impulse:interplanetary causes and polarization distribution, J. Geophys. Res.,107,1096-1100,2002
[6]MikiC, Z., Lee, M. A., An Introduction to Theory and Models of CMEs, Shocks, and Solar Energetic Particles, Space. Sci. Rev,123,57-80,2006
[7]Reames, D. V. Acceleration of energetic particles by shock waves from large solar flares, Space Sci. Rev.90,413-491,1999
[8]Feynman, J., and Gabriel, S. B, On space weather consequences and predictions, J. Geophys. Res.105,10543-10564.2000
[9]T'oth, G, Sokolov, I. V., Gombosi,.T. I., Chesney, D. R., Clauer, C. R., De Zeeuw, D. L., et al., Space Weather Modeling Framework:A new tool for the space science community, J. Geophys. Res,110, Cite ID A12226, DOI 10.1029/2005JA011126,2005
[10]Hu, Y. Q., Anisotropic propagation of flare-induced shocks, Chinese Science Bulletin, 43,402-404,1998
[11]Fry, C.D., Dryer, M., Smith, Z., Sun, W., Deehr, C.S., and Akasofu, S.-I, Forecasting solar wind structures and shock arrival times using an ensemble of models, J. Geophys. Res.,108,1070,2003
[12]Dryer, M., Interplanetary shock waves generated by solar flares, Space Sci. Rev.15, 403-468,1974
[13]Dryer, M. and Smart D. F., Dynamical models of coronal transients and interplanetary disturbances, Adv. Space Res,4,291-301,1984
[14]Smart, D. F., Shea, M. A., W. R. Barron, and M. Dryer, A simplified technique for estimating the arrival time of solar flare-initiated shocks, in Proceedings of STIP Workshop on Solar/Interplanetary Intervals, August 4-6,1982, Maynooth, Ireland, edited by M. A. Shea et al.,139-156, Bookcrafters, Inc., Chelsea, Mich.,1984.
[15]Smart, D. F., Shea, M. A., Dryer, M., Quintana, A., Gentile, L. C., Bathhurst A. A., Estimating the arrival time of solar flare-initiated shocks by considering them to be blast waves riding over the solar wind, in Proceedings of the Symposium on Solar-Terrestrial Predictions, edited by P. Simon, G. R. Heckman, and M. A. Shea, 471-481, U.S. Govt. Print. Off., Washington. D. C.,1986.
[16]Smart, D. F., Shea, M. A., A simplified model for timing the arrival of solar-flare-initiated shocks, J. Geophys. Res.,90,183-190,1985..
[17]Lewis, D. and Dryer, M, NOAA/SEL Contract Report, to U.S. Air Weather Service,1987
[18]Dryer, M., Shea, M. A., Smart, D. F., Collard, H. R., Mihalov, J. D., Wolfe, J. H., Warwick, J. R., On the observation of a flare generated shock wave at 9.7 AU by Pioneer 10, J. Geophys. Res.,83,1165-1168,1978.
[19]Wu, S. T., Dryer, M., and Han, S. M., Non-planar MHD model for solar flare-generated disturbances in the heliospheric equatorial plane, Solar Phys,84, 395-418,1983.
[20]Smith, Z., Dryer, M., MHD study of temporal and spatial evolution of simulated interplanetary shocks in the ecliptic plane within 1 AU, Sol. Phys.,129,387-405, 1990.
[21]Smith, Z., Dryer, M., The Interplanetary Shock Propagation Model:A model for predicting solar-flare-caused geomagnetic sudden impulses based on the 21/2 D MHD numerical simulation results from the Interplanetary Global Model (2D IGM), NOAA Tech. Memo., ERL/SEL-89, July 1995.
[22]Feng, X. S., Zhao, X. H., A new prediction method for the arrival time of interplanetary shocks, Solar Physics,238,167-186,2006
[23]Wei, F. S., The blast wave propagating in a moving medium with variable density, Chinese J. Space Sci.2,63-72.,1982
[24]Wei, F. S., Yang, G, Zhang, G, in Chen Biao and C. de Jager (eds.), Proceedings of Kunming Workshop on Solar Physics and Interplanetary Traveling Phenomena, Science Press, Beijing,1.2,1043,1983
[25]Hakamada, K., Akasofu, S. I., Simulation of three-dimensional solar wind disturbances and resulting geomagnetic storms, Space Sci. Rev.,32,3-70,1982
[26]Akasofu, S. I., Predicting geomagnetic storms as a space weather project, in Geophysical Monograph Series, edited by P. Song, G. Siscoe, and H. Singer, AGU, Washington, D. C.,2001
[27]Arge, C. N., Pizzo, V. J., Improvement in the prediction of solar wind conditions using near-real time solar magnetic field updates, J. Geophys. Res.105,10465-10480,2000
[28]Fry, C. D., Sun, W., Deehr, C. S., Dryer. M., Smith, Z., Akasofu, S-I., Tokumaru, M., Kojima, M., Improvements to the HAF solar wind model for space weather predictions, J. Geophys. Res.,106,20 985-21001,2001.
[29]McKenna-Lawlor, S. M. P., Dryer, M., Kartalev, M. D., Smith, Z., Fry, C. D., Sun, W., Deehr, C. S., Kecskemety, K., Kudela, K., Near real-time predictions of the arrival at Earth of flare-related shocks during Solar Cycle 23, J. Geophys. Res,111, A11103, doi:10.1029/2005JA011162.2006
[30]Smith, Z. K., Dryer, M., McKenna-Lawlor, S. M P., Fry, C. D., Deehr, C. S., Sun, W., Operational validation of HAFv2's predictions of interplanetary shock arrivals at Earth: Declining phase of Solar Cycle 23, J. Geophys. Res,114, A05106, doi:10.1029/2008JA013836,2009
[31]Reedy, R. C., Constraints on solar particle events from comparisons of recent events and million-years averages, Solar drivers of interplanetary and terrestrial disturbances ASP conference series,95,1996
[32]Smart, D., Shea, M., PPS73-A computerized'Event Mode'solor proton forecasting technique. Solar-Terrestrial Predictiions Proceeding of a Workshop, Boulder, US A,1,406-427,1979
[33]Feynman, J., Spitale, G., Wang, J. et al., Interplanetary proton fluence model-JPL 1991, J. Geophys. Res.98, A8,13281-13294,1993.
[34]Nymmik R. A., Radiation environment induced by cosmic ray particle fluxes in the international space station orbit according to recent galactic and solar cosmic ray models, Adv. Space Research 21 n.12,1689-1698,1998
[35]Aran A., Sanahuja, B., Lario, D., in'Solar Encounter:Proceedings of the First Solar Orbiter Workshop', p.157, Eds. B. Battrick & H. Sawaya-Lacoste,2001
[36]Aran, A., Sanahuja, B., Lario, D. A first step towards proton flux forecasting, Adv. Space Res.,36,2333-2338,2005
[37]Aran, A., Sanahuja, B., Lario, D., SOLPENCO:A solar particle engineering code, Adv. Space Res,37,1240-1246,2006
[38]Sanahuja, B., Aran, A., Lario, D., An engineering model for solar energetic particles in interplanetary space, ESA/ESTEC, December 2003
[39]Lario D., Sanahuja, B., Heras, A., M., Energetic particle events:efficiency of interplanetary shocks as 50kev
[41]Pizzo, V. J., A Three-Dimensional Model of Corotating Streams in the Solar Wind-Ⅰ. Theoretical Foundations, J. Geophys. Res.83,5,563-5,572,1978
[42]涂传饴等,日地空间物理,P177,科学出版社,1988
[43]Smith, E. J., Wolfre, J. H., Pioneer-10,11 observations of evolving solar wind streams and shocks beyond 1AU, Study of traveling interplanetary phenomena, P227. Shea, M. A., Smart, D. F, Wu, S. T., (eds), D. Reidel Pub. Co., Dordrecht-Holland/Boston-USA, 1977
[44]Collela, P., Woodward, P. R., The piecewise parabolic method (PPM) for gas-dynamical simulations, J. comput. Phys.,54,174-201,1984
[45]Dai, W., Woodward, P. R., A simple Riemann solver and high-order Godunov schemes for hyperbolic systems of conservation laws, J. comput. Phys.,121,51-65,1995
[46]Webber, E. J., Davis, L Jr, The angular momentum of the solar wind, Astrophys. J,148, 217-228,1967
[47]Smith, Z. K., Dryer, M., McKenna-Lawlor, S. M. P., Fry, C. D., Deehr, C. S., Sun, W, Operational validation of HAFv2's predictions of interplanetary shock arrivals at Earth: Dec.lining phase of Solar Cycle 23, J. Geophys. Res,114, A05106, doi:10.1029/2008JA013836,2009
[48]Boyd, T. J. M., Sanderson, J. J., The physics of plasma, Cambridge university press, 2003