On the Polar Bias in Ice Core 10Be Data
(2023) In Journal of Geophysical Research: Atmospheres 128(4).- Abstract
Cosmogenic radionuclide records from polar ice cores provide unique insights into past cosmic ray flux variations. They allow reconstructions of past solar activity, space weather, and geomagnetic field changes, and provide insights into past carbon cycle changes. However, all these applications rely on the proportionality of the ice core radionuclide records to the global mean production rate changes. This premise has been long debated from a model and data-perspective. Here, we address this issue through atmospheric mixing model experiments and comparison to independent data. We find that all mixing scenarios, which do not assume complete tropospheric mixing, result in a polar bias. This bias is more prominent for geomagnetic field... (More)
Cosmogenic radionuclide records from polar ice cores provide unique insights into past cosmic ray flux variations. They allow reconstructions of past solar activity, space weather, and geomagnetic field changes, and provide insights into past carbon cycle changes. However, all these applications rely on the proportionality of the ice core radionuclide records to the global mean production rate changes. This premise has been long debated from a model and data-perspective. Here, we address this issue through atmospheric mixing model experiments and comparison to independent data. We find that all mixing scenarios, which do not assume complete tropospheric mixing, result in a polar bias. This bias is more prominent for geomagnetic field changes than solar modulation changes. The most likely scenario, supported by independent geomagnetic field records and marine 10Be during the Laschamps geomagnetic field minimum, results in a dampening of geomagnetic field induced changes by 23%–37% and an enhancement of solar-induced changes by 7%–8%. During the Holocene, we do not find conclusive evidence for a polar bias. We propose a correction function that allows deconvolving the glacial ice core record in order to restore proportionality to the global mean signal.
(Less)
- author
- Adolphi, F. LU ; Herbst, K. LU ; Nilsson, A. LU and Panovska, S.
- organization
- publishing date
- 2023-02-27
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- atmospheric mixing, cosmogenic radionuclide, ice core, polar bias
- in
- Journal of Geophysical Research: Atmospheres
- volume
- 128
- issue
- 4
- article number
- e2022JD038203
- publisher
- Wiley-Blackwell
- external identifiers
-
- scopus:85148662034
- ISSN
- 2169-897X
- DOI
- 10.1029/2022JD038203
- language
- English
- LU publication?
- yes
- id
- adefd9b6-776d-4b54-8074-210a104034e8
- date added to LUP
- 2023-03-15 12:38:56
- date last changed
- 2023-03-15 12:38:56
@article{adefd9b6-776d-4b54-8074-210a104034e8,
abstract = {{<p>Cosmogenic radionuclide records from polar ice cores provide unique insights into past cosmic ray flux variations. They allow reconstructions of past solar activity, space weather, and geomagnetic field changes, and provide insights into past carbon cycle changes. However, all these applications rely on the proportionality of the ice core radionuclide records to the global mean production rate changes. This premise has been long debated from a model and data-perspective. Here, we address this issue through atmospheric mixing model experiments and comparison to independent data. We find that all mixing scenarios, which do not assume complete tropospheric mixing, result in a polar bias. This bias is more prominent for geomagnetic field changes than solar modulation changes. The most likely scenario, supported by independent geomagnetic field records and marine <sup>10</sup>Be during the Laschamps geomagnetic field minimum, results in a dampening of geomagnetic field induced changes by 23%–37% and an enhancement of solar-induced changes by 7%–8%. During the Holocene, we do not find conclusive evidence for a polar bias. We propose a correction function that allows deconvolving the glacial ice core record in order to restore proportionality to the global mean signal.</p>}},
author = {{Adolphi, F. and Herbst, K. and Nilsson, A. and Panovska, S.}},
issn = {{2169-897X}},
keywords = {{atmospheric mixing; cosmogenic radionuclide; ice core; polar bias}},
language = {{eng}},
month = {{02}},
number = {{4}},
publisher = {{Wiley-Blackwell}},
series = {{Journal of Geophysical Research: Atmospheres}},
title = {{On the Polar Bias in Ice Core <sup>10</sup>Be Data}},
url = {{http://dx.doi.org/10.1029/2022JD038203}},
doi = {{10.1029/2022JD038203}},
volume = {{128}},
year = {{2023}},
}