noaa-forcing-10436 Antarctic Last Millennium 10Be Stack and Solar Irradiance Reconstruction Delaygue, G.; Bard, E. Antarctic Last Millennium 10Be Stack and Solar Irradiance Reconstruction 2010-04-16 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/10436 Investigator G. Delaygue Investigator E. Bard earth science paleoclimate ice cores 10Be,bulk ice,null,standard deviation unit,null,ice cores,composited,null,N,variations relative to the 843-1876 AD average earth science paleoclimate climate forcing age,null,null,year Common Era,null,climate forcing,null,null,N,null earth science paleoclimate climate forcing solar modulation potential,null,null,megavolt,null,climate forcing,null,null,N,assuming a 70% contribution of the mid-latitudes to Be-10 production earth science paleoclimate climate forcing solar irradiance,null,null,watt per square meter,null,climate forcing,null,null,N,assuming a 0.08% decrease at the Maunder Minimum earth science paleoclimate climate forcing solar modulation potential,null,null,megavolt,null,climate forcing,null,null,N,assuming all Be-10 produced at high latitudes earth science paleoclimate climate forcing solar geoscientificInformation Solar Forcing Reconstruction 695 AD 1982 AD 1255 cal yr BP -32 cal yr BP Complete -77.32 -77.32 38.7 38.7 3810 3810 Continent Antarctica Dome Fuji>LATITUDE -77.32>LONGITUDE 38.7 None Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site. English DOC/NOAA/NESDIS/NCEI National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce https://www.ncdc.noaa.gov/data-access/paleoclimatology-data DATA Center Contact Bruce Bauer bruce.a.bauer@noaa.gov paleo@noaa.gov 303-497-6280 303-497-6513

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Boulder CO 80305-3328 USA online ASCII Delaygue, G. and E. Bard. 2010. An Antarctic view of Beryllium-10 and solar activity for the past millennium. Climate Dynamics, Published online 1 April 2010. DOI: 10.1007/s00382-010-0795-1

Beryllium-10 in ice provides a valuable proxy of solar activity. However, complex production pathways, atmospheric transport, and deposition processes impede its quantitative interpretation. Here, we examine the influence of deposition processes on two Be-10 ice core records from Central Antarctica (South Pole and Dome Fuji stations), covering the last millennium. We try to quantify how Be-10 variations in ice relate to variations in Be-10 production, and the bias associated to this relationship. An independent bias estimation is provided by comparing atmospheric radiocarbon variations reconstructed from tree rings and deduced from Be-10 variations. Both techniques suggest an uncertainty of the order of 10% in Be-10 production. This uncertainty estimate does not account for the geographical origin of Be-10, which remains a major issue. Because both Be-10 records are so similar, we propose to average them as a means to decrease the unshared (non solar) variability. This average record provides a new reconstruction of solar modulation parameter PHI and total solar irradiance over the last ~1,300 years. The lowest solar activity is found during the so-called Spörer Minimum (around AD 1450). The highest activities are found during the 8th century and over the last decades: as shown in previous studies, our results suggest that the recent solar activity is not exceptionally high for the last millennium. STUDY NOTES: Two Antarctic records of Be-10 concentrations covering the last millennium are normalized and averaged in order to smooth out non-forced variability. This stack is corrected for geomagnetic variations and converted into solar modulation parameter PHI and total solar irradiance (TSI) over the period of years 695-1982 AD. Stack of Be-10 Antarctic records published by Raisbeck et al. 1990 and Horiuchi et al. 2008, using the C-14 adjusted timescale for the latter. The stack is corrected for geomagnetic variations reconstructed by Korte et al. 2009 with the production sensitivity of Wagner et al. 2000. The solar modulation parameter PHI is calculated following McCracken et al. 2004 method, i.e. by calibrating the stack to an average level of 645 MV over the period 1944-1966 AD. The sensitivity of the Be-10 production to PHI is from Webber and Higbie 2003, assuming that Be-10 is produced at 70% in mid-latitudes and 30% locally ("mix" case) or purely locally ("local" case). Total Solar Irradiance (TSI) is calculated from either of the PHI time series, assuming an average modern maximum of 1365.5 W/m**2 (year 1969 AD) and a 0.08% decrease at the Maunder Minimum (year 1692 AD) (most likely value of IPCC AR4 p.192).

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/solar_variability/delaygue2010be10.xls GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/solar_variability/delaygue2010be10.txt USA/NOAA DIF Version 9.8.4 2018-12-11 2018-12-11