Knowledge of the long-term variability of solar activity is of both astrophysical and geoscientific interest. Reconstructions of solar activity over multiple millennia are traditionally based on cosmogenic isotopes 14C or 10Be measured in natural terrestrial archives, but the two isotopes exhibit significant differences on millennial time scales, so that our knowledge of solar activity at this time scale remains somewhat uncertain. Here we present a new potential proxy of solar activity on the centennial-millennial time scale, based on a chemical tracer, viz. nitrate content in an ice core drilled at Talos Dome (Antarctica). We argue that this location is optimal for preserving the solar signal in the nitrate content during the Holocene. By using the firn core from the same location we show that the 11-year and Gleissberg cycles are present with the variability of 10 - 25 % in nitrate content in the pre-industrial epoch. This is consistent with the results of independent efforts of modeling HNO 3 and NO y in Antarctic near surface air. However, meteorological noise on the interannual scale makes it impossible to resolve individual solar cycles. Based on different processes of formation and transport compared to cosmogenic isotopes, it provides new, independent insight into long-term solar activity and helps resolve the uncertainties related to cosmogenic isotopes as diagnostics of solar activity.

Nitrate in Polar Ice: A New Tracer of Solar Variability / R. Traversi; I.G. Usoskin; S.K. Solanki; S. Becagli; M. Frezzotti; M. Severi; B. Stenni; R. Udisti. - In: SOLAR PHYSICS. - ISSN 0038-0938. - ELETTRONICO. - 280:(2012), pp. 237-254. [10.1007/s11207-012-0060-3]

Nitrate in Polar Ice: A New Tracer of Solar Variability

TRAVERSI, RITA;BECAGLI, SILVIA;SEVERI, MIRKO;UDISTI, ROBERTO
2012

Abstract

Knowledge of the long-term variability of solar activity is of both astrophysical and geoscientific interest. Reconstructions of solar activity over multiple millennia are traditionally based on cosmogenic isotopes 14C or 10Be measured in natural terrestrial archives, but the two isotopes exhibit significant differences on millennial time scales, so that our knowledge of solar activity at this time scale remains somewhat uncertain. Here we present a new potential proxy of solar activity on the centennial-millennial time scale, based on a chemical tracer, viz. nitrate content in an ice core drilled at Talos Dome (Antarctica). We argue that this location is optimal for preserving the solar signal in the nitrate content during the Holocene. By using the firn core from the same location we show that the 11-year and Gleissberg cycles are present with the variability of 10 - 25 % in nitrate content in the pre-industrial epoch. This is consistent with the results of independent efforts of modeling HNO 3 and NO y in Antarctic near surface air. However, meteorological noise on the interannual scale makes it impossible to resolve individual solar cycles. Based on different processes of formation and transport compared to cosmogenic isotopes, it provides new, independent insight into long-term solar activity and helps resolve the uncertainties related to cosmogenic isotopes as diagnostics of solar activity.
2012
280
237
254
R. Traversi; I.G. Usoskin; S.K. Solanki; S. Becagli; M. Frezzotti; M. Severi; B. Stenni; R. Udisti
File in questo prodotto:
File Dimensione Formato  
Traversi_SP_2012.pdf

Accesso chiuso

Tipologia: Versione finale referata (Postprint, Accepted manuscript)
Licenza: Tutti i diritti riservati
Dimensione 843.91 kB
Formato Adobe PDF
843.91 kB Adobe PDF   Richiedi una copia

I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificatore per citare o creare un link a questa risorsa: https://hdl.handle.net/2158/774722
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 44
  • ???jsp.display-item.citation.isi??? 46
social impact