A 600‐year annual ¹⁰Be record from the NGRIP ice core, Greenland

Abstract

Despite the extensive use of 10Be as the most significant information source on past solar activity, there has been only one record (Dye‐3, Greenland) providing annual resolution over several centuries. Here we report a new annual resolution 10Be record spanning the period 1389–1994 AD, measured in an ice core from the NGRIP site in Greenland. NGRIP and Dye‐3 10Be exhibits similar long‐term variability, although occasional short term differences between the two sites indicate that at least two high resolution 10Be records are needed to assess local variations and to confidently reconstruct past solar activity. A comparison with sunspot and neutron records confirms that ice core 10Be reflects solar Schwabe cycle variations, and continued 10Be variability suggests cyclic solar activity throughout the Maunder and Spörer grand solar activity minima. Recent 10Be values are low; however, they do not indicate unusually high recent solar activity compared to the last 600 years.

Influence of the Schwabe/Hale solar cycles on climate change during the Maunder Minimum

“…The profile is characterized by the sharp peak of cosmic ray flux at solar cycle minima when the magnetic polarity of the Sun is negative, resulting in the enhancement of the Hale cycle in cosmic ray variation. This profile has been recently supported by the beryllium-10 record from Greenland ice core (Berggren et al, 2009). In the record of beryllium-10, three sharp peaks are recognized at the beginning of the Maunder Minimum, ∼1700AD and in between.…”

Synchronized Northern Hemisphere climate change and solar magnetic cycles during the Maunder Minimum

“…Normally the tilt angle does not approach to ∼0 even at the minima of the solar cycle, but this may happen when solar activity is extremely low such as during the Maunder Minimum. The possibility of annualscale enhancements of GCR flux at solar minima of negative polarity is supported by a 10 Be record from the NGRIP ice core in Greenland (38). The record shows quasi-periodic steep peaks of 10 Be flux around the Maunder Minimum (open circles in Fig.…”

Solar change and climate: an update in the light of the current exceptional solar minimum

“…The rise of open solar flux since the MM ( §8) has been inferred to give the long-term decline in GCRs, as shown by the cosmogenic isotopes, for example, in the recently published new ice core data (Berggren et al 2009). It has been postulated that these GCRs increase low-altitude cloud for which the dominant effect on the energy balance is due to the change in the albedo.…”