eCite Digital Repository

No coincident nitrate enhancement events in polar ice cores following the largest known solar storms


Mekhaldi, F and McConnell, JR and Adolphi, F and Arienzo, MM and Chellman, NJ and Maselli, OJ and Moy, AD and Plummer, CT and Sigl, M and Muscheler, R, No coincident nitrate enhancement events in polar ice cores following the largest known solar storms, Journal of Geophysical Research: Atmospheres, 122, (21) pp. 11,900-11,913. ISSN 2169-897X (2017) [Refereed Article]


Copyright Statement

2017. American Geophysical Union

DOI: doi:10.1002/2017JD027325


Knowledge on the occurrence rate of extreme solar storms is strongly limited by the relatively recent advent of satellite monitoring of the Sun. To extend our perspective of solar storms prior to the satellite era and because atmospheric ionization induced by solar energetic particles (SEPs) can lead to the production of odd nitrogen, nitrate spikes in ice cores have been tentatively used to document both the occurrence and intensity of past SEP events. However, the reliability of the use of nitrate in ice records as a proxy for SEP events is strongly debated. This is partly due to equivocal detection of nitrate spikes in single ice cores and possible alternative sources, such as biomass burning plumes. Here we present new continuous high-resolution measurements of nitrate and of the biomass burning species ammonium and black carbon, from several Antarctic and Greenland ice cores. We investigate periods covering the two largest known SEP events of 775 and 994 Common Era as well as the Carrington event and the hard SEP event of February 1956. We report no coincident nitrate spikes associated with any of these benchmark events. We also demonstrate the low reproducibility of the nitrate signal in multiple ice cores and confirm the significant relationship between biomass burning plumes and nitrate spikes in individual ice cores. In the light of these new data, there is no line of evidence that supports the hypothesis that ice cores preserve or document detectable amounts of nitrate produced by SEPs, even for the most extreme events known to date.

Item Details

Item Type:Refereed Article
Keywords:ice cores, nitrate, solar storms
Research Division:Earth Sciences
Research Group:Physical geography and environmental geoscience
Research Field:Glaciology
Objective Division:Environmental Policy, Climate Change and Natural Hazards
Objective Group:Understanding climate change
Objective Field:Understanding climate change not elsewhere classified
UTAS Author:Moy, AD (Dr Andrew Moy)
UTAS Author:Plummer, CT (Mr Christopher Plummer)
ID Code:122198
Year Published:2017
Web of Science® Times Cited:12
Deposited By:CRC-Antarctic Climate & Ecosystems
Deposited On:2017-11-06
Last Modified:2022-06-29
Downloads:105 View Download Statistics

Repository Staff Only: item control page