Empfehlenswert! Ich habe hier seit einigen Jahren zu dem Thema das schwankende Sonnenaktivität ursächlich sind für Klimaschwankungen auf der Erde statt CO2.
"Die Sonne ist der Motor des irdischen Klimas. Ohne ihre Energie gäbe es keine Ozeane, keine Atmosphäre und kein Leben. Trotzdem spielt die Sonne in vielen aktuellen Klimadiskussionen nur eine Nebenrolle. Häufig wird argumentiert, dass die Schwankungen der Sonnenleistung zu gering seien, um relevante Klimaänderungen auszulösen.
Eine neue im Juli 2026 im Fachblatt Heritage veröffentlichte wissenschaftliche Arbeit aus Italien zeigt nun, dass diese Betrachtungsweise möglicherweise zu kurz greift. Die Autoren untersuchten die Klimageschichte des Mittelmeerraums über einen Zeitraum von rund 2.000 Jahren und fanden Hinweise darauf, dass Veränderungen der Sonnenaktivität mit langfristigen Schwankungen der Niederschlagsverteilung verbunden waren. Dabei geht es nicht um eine simple Aussage wie „mehr Sonne bedeutet wärmeres Klima“. Das Klimasystem ist wesentlich komplexer. Die Sonne kann über verschiedene Prozesse die atmosphärische Zirkulation beeinflussen – und damit verändern, wo, wann und wie viel Niederschlag fällt. ..."
From the abstract:
"This study presents a meta-analysis of relatively high-resolution paleohydrological proxies derived from geological archives in Sardinia and in the Italian Peninsula–Sicily over the last 2000 years, with particular emphasis on the Medieval Warm Period (MWP) and the Little Ice Age (LIA).
The investigated climate proxies, ranging from annual-decadal to centennial resolution, include terrestrial and marine sediment cores, glaciers, pollen spectra, speleothems, lake-level fluctuations, as well as sedimentary and geomorphological inventories.
Such datasets were analyzed through holistic and stratigraphic approaches along West–East and North–South transects across the central Mediterranean. Limited temporal resolution and incomplete stratigraphic continuity of several paleoclimatic records from the investigated regions thwart full reconstructions of paleohydrological trends.
Nevertheless, the presented meta-analysis has enabled:
(1) the recognition of reliable paleoclimatic correlations between the two regions, which exhibit long-lasting anti-phase hydroclimatic trends (wetter conditions in Sardinia and drier conditions in central Italy during the MWP, with the opposite pattern during the LIA); and
(2) the identification of the North Atlantic Oscillation (NAO) as the primary driver of these paleohydrological variations.
The significance of this anti-phase pattern is discussed in the context of the North–South and West–East climatic dipoles identified in the Mediterranean region during the middle to late Holocene.
Furthermore, we assessed the potential of the investigated paleohydrological network to:
(1) compare reconstructed hydrological patterns with mean temperature and precipitation records derived from empirical and model-based climate reconstructions in southern Europe and the Mediterranean; and
(2) identify gaps in data coverage that currently limit our understanding of high-resolution spatiotemporal hydrological variability and dynamics
The hydroclimatic pattern in Sardinia and in the Italian Peninsula–Sicily has exhibited marked spatio-temporal divergences, with major hydroclimatic transitions coincident with well-known solar minima over the last millennium, thus suggesting a possible cause-and-effect relationship. The interpretations presented in this study provide a framework for understanding how changes in the paleoclimatic variability of water resources may have influenced different regions of Italy since the Middle Ages, potentially affecting societal transitions as well as historical and socioeconomic dynamics.
Comparison of the multidecadal-to-centennial reconstructions of paleohydrological patterns is presented for both areas, pending the development of new, higher-resolution, and more precisely dated proxies from the Italian records. Their importance is emphasized in order to improve reconstructions of past climate variability and to enhance assessments of future climate trajectories."
No comments:
Post a Comment