Solar cosmic ray events for the period 1561–1994: 1. Identification in polar ice, 1561–1950

The geophysical significance of the thin nitrate-rich layers that have been found in both Arctic and Antarctic firn and ice cores, dating from the period 1561–1991, is examined in detail. It is shown that variations of meteorological origin dominate the record until the snow has consolidated to high-density firn some 30 years after deposition. The thin nitrate layers have a characteristic short timescale ( 30 MeV solar proton fluence. The proton fluences (omnidirectional fluence cm−2) derived from the 70 largest impulsive nitrate events between 1561 and 1950 are tabulated. The proton fluence probability distribution derived from these large impulsive nitrate events are in good agreement with earlier studies of the cumulative probabilities of solar proton events and with the observation of cosmogenic isotopes in moon rocks. The cumulative probability curve derived from the impulsive nitrate events indicates a rapidly decreasing probability of occurrence of >30 MeV solar proton events having an omnidirectional fluence exceeding 6 × 109 cm−2. It is concluded that the impulsive nitrate events are reliable indicators of the occurrence of large fluence solar proton events and that they provide a quantitative measure of these events. It is further concluded that the impulsive nitrate events will permit the study of solar activity for many thousands of years into the past.

[1]  R. Hodgson,et al.  On a curious Appearance seen in the Sun , 1859 .

[2]  G. Brasseur,et al.  Future changes in stratospheric ozone and the role of heterogeneous chemistry , 1990, Nature.

[3]  S. Forbush,et al.  Three Unusual Cosmic-Ray Increases Possibly Due to Charged Particles from the Sun , 1946 .

[4]  H. Kanzawa,et al.  Stratospheric Sudden Cooling after Solar Proton Event over Syowa Station, Antarctica. , 1992 .

[5]  K. Mccracken.  A correlation between the emission of white light and cosmic radiation by a solar flare , 1959 .

[6]  Donald V. Reames,et al.  Particle acceleration at the Sun and in the heliosphere , 2013 .

[7]  E. Parker,et al.  Solar Cosmic Rays of February, 1956 and Their Propagation through Interplanetary Space , 1956 .

[8]  F. Vitt,et al.  A comparison of sources of odd nitrogen production from 1974 through 1993 in the Earth's middle atmosphere as calculated using a two‐dimensional model , 1996 .

[9]  M. Hayashi,et al.  Nitric Acid Trihydrate Particle Formation in the Polar Stratosphere and Its Effect on Nitric Acid Transport to the Troposphere , 1991 .

[10]  R. Mcpeters,et al.  Effect of solar proton events on the middle atmosphere during the past two solar cycles as computed using a two‐dimensional model , 1990 .

[11]  R. Mcpeters,et al.  The effects of the October 1989 solar proton events on the stratosphere as computed using a three-dimensional model , 1993 .

[12]  S. Self,et al.  The volcanic explosivity index (VEI) an estimate of explosive magnitude for historical volcanism , 1982 .

[13]  M. Shea,et al.  The Flux and Fluence of Major Solar Proton Events and their Record in Antarctic Snow , 1993 .

[14]  J. Frederick,et al.  Production of odd nitrogen in the stratosphere and mesosphere: An intercomparison of source strengths , 1980 .

[15]  E. Cliver,et al.  An estimate of the maximum speed of the solar wind, 1938-1989 , 1990 .

[16]  E. Zeller,et al.  Anomalous nitrate concentrations in polar ice cores—Do they result from solar particle injections into the polar atmosphere? , 1995 .

[17]  L. Thomason,et al.  Use of stratospheric aerosol properties as diagnostics of Antarctic vortex processes , 1993 .

[18]  F. Vitt,et al.  Computed contributions to odd nitrogen concentrations in the Earth's polar middle atmosphere by energetic charged particles. , 2000 .

[19]  M. Shea,et al.  Solar cosmic ray events for the period 1561–1994: 2. The Gleissberg periodicity , 2001 .

[20]  Linwood B. Callis,et al.  NOy formed by precipitating electron events in 1991 and 1992: Descent into the stratosphere as observed by ISAMS , 1998 .

[21]  P. Mayewski,et al.  Glaciochemistry of polar ice cores: A review , 1997 .

[22]  R. Reedy.  Constraints on solar particle events from comparisons of recent events and million-year averages , 1995 .

[23]  M. Gussenhoven,et al.  Systematics of the equatorward diffuse auroral boundary , 1983 .

[24]  P. Laj,et al.  Modified HNO3 seasonality in volcanic layers of a polar ice core: Snow-pack effect or photochemical perturbation? , 1993 .

[25]  M. Shea,et al.  A summary of major solar proton events , 1990 .

[26]  E. Zeller,et al.  Evidence of individual solar proton events in Antarctic snow , 1990 .

[27]  P. V. Velthoven,et al.  On the magnitude of transport out of the Antarctic polar vortex , 1997 .

[28]  O. Shumilov,et al.  Enhancement of stratospheric aerosols after solar proton event , 1996 .

[29]  R. C. Carrington.  Description of a Singular Appearance seen in the Sun on September 1, 1859 , 1859 .

[30]  T. Dunkerton,et al.  On the Mean Meridional Mass Motions of the Stratosphere and Mesosphere , 1978 .

[31]  L. Křivský,et al.  Solar activity, aurorae and climate in Central Europe in the last 1000 years. , 1988 .

[32]  D. Baker,et al.  A 2‐D model simulation of downward transport of NOy into the stratosphere: Effects on the 1994 austral spring O3and NOy , 1996 .

[33]  D. K. Bailey.  Polar-cap absorption , 1964 .

[34]  M. A. Shea,et al.  Fifty Years of Cosmic Radiation Data , 2000 .