Harvard-Smithsonian Center for Astrophysics findet Zyklen mit Perioden um 2300 und 1000 Jahren in globalen Klimaarchiven

Im Juli 2014-Heft der angesehenen Fachzeitschrift Earth-Science Reviews erscheint ein Artikel einer Forschergruppe um Willie Soon vom Harvard-Smithsonian Center for Astrophysics im US-amerikanischen Cambridge (Massachusetts), in dem es um klimatische Zyklen und ihre möglichen solaren Auslöser geht. Im Rahmen einer umfangreichen Datenanalyse identifizierten die Wissenschaftler gleich drei wichtige Zyklen, von denen wir in unserem Buch den 2300-Jahres-Hallstatt sowie den 1000-Jahres-Eddyzyklus vorgestellt haben. Bei weiteren Zyklen im Bereich von 1500-1800 Jahren ist noch unklar, ob es sich um klimasysteminterne Ozeanzyklen oder abgeleitete Sonnenzyklen handelt.

Im Folgenden die Kurzfassung der Arbeit:

A review of Holocene solar-linked climatic variation on centennial to millennial timescales: Physical processes, interpretative frameworks and a new multiple cross-wavelet transform algorithm

We report on the existence and nature of Holocene solar and climatic variations on centennial to millennial timescales. We introduce a new solar activity proxy, based on nitrate (NO3) concentration from the Talos Dome ice core, East Antarctica. We also use a new algorithm for computing multiple-cross wavelet spectra in time–frequency space that is generalized for multiple time series (beyond two). Our results provide a new interpretive framework for relating Holocene solar activity variations on centennial to millennial timescales to co-varying climate proxies drawn from a widespread area around the globe. Climatic proxies used represent variation in the North Atlantic Ocean, Western Pacific Warm Pool, Southern Ocean and the East Asian monsoon regions. Our wavelet analysis identifies fundamental solar modes at 2300-yr (Hallstattzeit), 1000-yr (Eddy), and 500-yr (unnamed) periodicities, leaves open the possibility that the 1500–1800-yr cycle may either be fundamental or derived, and identifies intermediary derived cycles at 700-yr and 300-yr that may mark rectified responses of the Atlantic thermohaline circulation to external solar modulation and pacing. Dating uncertainties suggest that the 1500-yr and 1800-yr cycles described in the literature may represent either the same or two separate cycles, but in either case, and irrespective too of whether it is a fundamental or derived mode in the sense of Dima and Lohmann (2009), the 1500–1800-yr periodicity is widely represented in a large number of paleoclimate proxy records. It is obviously premature to reject possible links between changing solar activity at these multiple scales and the variations that are commonly observed in paleoclimatic records.