Wie die Sonne Einfluss auf das europäische Klima nimmt

Das gigantische Kernfusionskraftwerk der Sonne versorgt die Erde zuverlässig mit Energie. Die gängige Lehrmeinung des IPCC ist jedoch, dass Schwankungen der Sonnenaktivität keinerlei Auswirkungen auf das Klima der Erde haben. Einige Klimawissenschaftler widersprechen dem IPCC und sehen sehr wohl einen signifikanten Einfluss der Sonne auf das Erdklima.

Am 1. Juli 2019 erschien in Advances in Space Research eine Studie von Bhargawa & Sing:

Solar irradiance, climatic indicators and climate change – An empirical analysis

Since the Sun is the main source of energy for our planet therefore even a slight change in its output energy can make a huge difference in the climatic conditions of the terrestrial environment. The rate of energy coming from the Sun (solar irradiance) might affect our climate directly by changing the rate of solar heating of the Earth and the atmosphere and indirectly by changing the cloud forming processes. In the present paper, based on stability test of Vector Auto Regressive (VAR) model, we have used the impulse response functions and the variance decomposition method for the analysis of climate variability. We have examined the possible connections among the solar irradiance and some climate indicators, viz., the global temperature anomaly, the global mean sea level, the global sea-ice extent and the global precipitation anomaly occurred during last forty years (1978–2017). In our investigation, we have observed that the impact of solar irradiance on the global surface temperature level in next decade will increase by ∼4.7% while the global mean sea level will increase about 0.67%. In the meantime, we have noticed about 5.3% decrement in the global sea-ice extent for the next decade. In case of the global precipitation anomaly we have not observed any particular trend just because of the variable climatic conditions. We also have studied the effect of CO2 as anthropogenic forcing where we have observed that the global temperature in the next decade will increase by 2.7%; mean sea level will increase by 6.4%. Increasing abundance in CO2 will be responsible for about 0.43% decrease in the sea-ice extent while there will not be any change in the precipitation pattern.

Im Mai 2018 hatten bereits Chassiot et al. eine charakteristische Millenniumszyklik aus dem Zentralmassif Frankreichs berichtet, die offenbar von solaren Schwankungen und Ozeanzyklen angetrieben wird:

A 7000-year environmental history and soil erosion record inferred from the deep sediments of Lake Pavin (Massif Central, France)

A 14-m long sedimentary sequence (core PAV12) was collected in the deepest part of Lake Pavin, a maar lake located in the French Massif Central. The PAV12 sedimentary sequence documents the lake’s environmental evolution since its formation 7000 years ago. The relationships between the catchment’s vegetation cover, erosion processes and changes in trophic status were shown using a multi-proxy characterization of mineral and organic fractions supported by palynological data. The record shows a succession of lithological units starting at the base with volcanoclastic material corresponding to the early stage of Lake Pavin. The deposition of organic-rich and diatomaceous sedimentary units above volcanoclastic material indicates an evolution toward a pristine lacustrine state. The Late Holocene environmental history of this lake is marked by two tipping points reflecting major environmental disturbances at ca. 4000 cal BP and after the deposition of erosive mass-wasting deposits (MWDs) at 1350 cal BP (AD 600) and 650 cal BP (AD 1300). The upper unit of core PAV12, which corresponds to the past 700 years, indicates that one of these MWDs was likely the driving force behind a major limnological change marked by a shift in redox-sensitive elements (i.e., current meromictic lacustrine state). The palynological diagram indicates a forested catchment where woodland clearances and agro-pastoral activities have remained limited except over the last 700 years. These findings suggest restricted human impact within the watershed compared to other regional archives. The reconstruction of the Lake Pavin erosion record determined from titanium and red amorphous particle fluxes highlights phases of enhanced erosion at ca. 6.5–5.5, 4.1–3.8, 3.5, 2.8–2.6, 1.6–1.4 cal kyr BP and during the Little Ice Age (LIA). A comparison between this erosion record, palaeoenvironmental archives from Western Europe and palaeoclimatic data supports an Atlantic signal driving precipitation patterns over Lake Pavin at centennial to millennial timescales. The influence of local human activities, even on a small scale, cannot be completely discounted as their impact on erosional processes may be amplified in a steep catchment such as that found in Lake Pavin.

Aus den Conclusions:

[…] Consequently, the Lake Pavin erosion record appears primarily related to hydroclimatic fluctuations. The matching of enhanced terrigenous inputs with NAO negative phases and low TSI values supports both Atlantic and solar forcing at a centennial to millennial scale over the Holocene.

Auch das rumänische Klima scheint einer solaren Beeinflussung zu unterliegen, wie Sfica et al. 2018 dokumentierten:

Solar signal on regional scale: A study of possible solar impact upon Romania’s climate

The topic of this paper is to investigate whether a solar signal can be identified in the variation of climatic parameters at regional scale. This was done using eight climate parameters recorded in Romania during 1961–2013 which corresponds with four cycles of solar activity. The methodology is based on trend, composite and wavelet analysis. A weak solar influence with a clear spatial pattern was identified, especially during the cold season, on temperature and cloud cover. During the warm season, the influence seems to be spurious. A clear difference between the north-eastern Romania and the rest of the country was found in the response of local climate to solar trigger. The mountain chain induces persistent disparities in the distribution of the most parameters, which supports the fact that orography is an important feature to be considered when analysing solar imprint at regional scale. Possible mechanisms for the solar influence on climate at regional and local scale are proposed.

Aus dem März 2019 stammt dieses Paper von Moreno et al., das sich mit dem Klimawandel in Portugal beschäftigt. In diesem Fall moduliert die Sonne die Temperaturen von Frühling und Sommer sowie die Nordatlantische Oszillation (NAO:

Foraminiferal evidence of major environmental changes driven by the sun-climate coupling in the western Portuguese coast (14th century to present)

New paleoclimatic data from the Casa Branca salt marsh, in the southwest coast of Portugal, are compared with records previously published on the northwest coast (Caminha salt marsh) to offer a more comprehensive overview of the environmental evolution of the west Iberian margin over the last six centuries. These reconstructions are based on the foraminiferal records of two dated sediment cores retrieved from the high marsh settings and supported by geochemical-sedimentological data. Both marshes were originally formed in the AD 1300s, between the Medieval Climatic Anomaly (MCA) and the Little Ice Age (LIA), highlighting a major episode of increased sediment supply in lower estuaries linked to climate-driven changes in continental runoff. Afterwards, the two marshes evolved under different climatic regimes as reflected by their foraminiferal assemblages. The environmental conditions are characterized by higher salinity in Casa Branca (southwest), with Jadammina macrescens and Trochammina inflata as dominant species, than in Caminha (northwest), where Haplophragmoides spp. dominates. We suggest that a long-term trend of a net gain in evapotranspiration at Casa Branca inducing a higher marsh salinity baseline may explain this microfaunal contrast. Trochammina inflata seems to be a good indicator of drier periods in the studied area, connected to key events of aeolian large-dust input to the southwest coast of Portugal. The influence of the most important climate drivers was assessed, namely external (solar) and internal (North Atlantic Oscillation – NAO) forcings. Spectral and wavelet transform coherence analyses were used to detect solar footprints on foraminiferal and climate-related time series. A main significant quasi-periodicity was identified within the range of the secular Gleissberg cycle of solar activity modulating the annual NAO and regional spring-summer (simulated) temperatures after AD 1700. This stronger solar-climate coupling may be related to the known upward secular trend in the total solar irradiance after the Maunder Minimum.