An dieser Stelle sind wissenschaftliche Studien gesammelt, die sich mit dem Thema Solarstrahlung und w:globale Erwärmung beschäftigen.
Die Frage, wie stark die globale Erwärmung durch solare Aktivitäten beeinflusst wird, hat auch Einfluss auf die berechnete Klimawirksamkeit von w:Treibhausgasen. Aus diesem Grund habe ich auf dieser Benutzerseite alle relevanten wissenschaftlichen Studien zum Thema gesammelt, anhand deren Wikipedia-Artikel ausgerichtet werden können.
Bereitgestellt sind immer die Autor/innen, der Titel, der Abstract sowie ein Link zur Studie, wenn verfügbar.
Neueste Studien bitte oben anfügen!
Foukal et al.[Bearbeiten]
Foukal, P., C. Fröhlich, H. Spruit und T. M. L. Wigley (2006): Variations in solar luminosity and their effect on the Earth's climate, in: Nature, 443, S. 161-166, 14. September, doi:10.1038/nature05072, siehe Abstract online
"Variations in the Sun's total energy output (luminosity) are caused by changing dark (sunspot) and bright structures on the solar disk during the 11-year sunspot cycle. The variations measured from spacecraft since 1978 are too small to have contributed appreciably to accelerated global warming over the past 30 years. In this Review, we show that detailed analysis of these small output variations has greatly advanced our understanding of solar luminosity change, and this new understanding indicates that brightening of the Sun is unlikely to have had a significant influence on global warming since the seventeenth century. Additional climate forcing by changes in the Sun's output of ultraviolet light, and of magnetized plasmas, cannot be ruled out. The suggested mechanisms are, however, too complex to evaluate meaningfully at present."
<ref name="Foukal et al. 2006">Foukal, P., C. Fröhlich, H. Spruit und T. M. L. Wigley (2006): ''Variations in solar luminosity and their effect on the Earth's climate'', in: Nature, 443, S. 161-166, 14. September, doi:10.1038/nature05072, siehe Abstract [http://www.nature.com/nature/journal/v443/n7108/abs/nature05072.html online]</ref>
Scafetta, N. und B. J. West (2006): Phenomenological solar contribution to the 1900–2000 global surface warming, in: Geophysical Research Letters, 33, L05708, doi:10.1029/2005GL025539, siehe Abstract online
"We study the role of solar forcing on global surface temperature during four periods of the industrial era (1900–2000, 1900–1950, 1950–2000 and 1980–2000) by using a sun-climate coupling model based on four scale-dependent empirical climate sensitive parameters to solar variations. We use two alternative total solar irradiance satellite composites, ACRIM and PMOD, and a total solar irradiance proxy reconstruction. We estimate that the sun contributed as much as 45–50% of the 1900–2000 global warming, and 25–35% of the 1980–2000 global warming. These results, while confirming that anthropogenic-added climate forcing might have progressively played a dominant role in climate change during the last century, also suggest that the solar impact on climate change during the same period is significantly stronger than what some theoretical models have predicted."
<ref name="Scafetta/West 2006">Scafetta, N. und B. J. West (2006): '''Phenomenological solar contribution to the 1900–2000 global surface warming''', in: Geophysical Research Letters, 33, L05708, doi:10.1029/2005GL025539, siehe Abstract [http://www.agu.org/pubs/crossref/2006/2005GL025539.shtml online]</ref>
Braun et al.[Bearbeiten]
Holger Braun, Marcus Christl, Stefan Rahmstorf, Andrey Ganopolski, Augusto Mangini, Claudia Kubatzki, Kurt Roth and Bernd Kromer (2005): Possible solar origin of the 1,470-year glacial climate cycle demonstrated in a coupled model, in: Nature 438, S. 208-211, 10. November, doi:10.1038/nature04121, siehe Abstract online
"Many palaeoclimate records from the North Atlantic region show a pattern of rapid climate oscillations, the so-called Dansgaard–Oeschger events, with a quasi-periodicity of approx. 1,470 years for the late glacial period. Various hypotheses have been suggested to explain these rapid temperature shifts, including internal oscillations in the climate system and external forcing, possibly from the Sun. But whereas pronounced solar cycles of approx. 87 and approx. 210 years are well known, a approx. 1,470-year solar cycle has not been detected8. Here we show that an intermediate-complexity climate model with glacial climate conditions simulates rapid climate shifts similar to the Dansgaard–Oeschger events with a spacing of 1,470 years when forced by periodic freshwater input into the North Atlantic Ocean in cycles of approx. 87 and approx. 210 years. We attribute the robust 1,470-year response time to the superposition of the two shorter cycles, together with strongly nonlinear dynamics and the long characteristic timescale of the thermohaline circulation. For Holocene conditions, similar events do not occur. We conclude that the glacial 1,470-year climate cycles could have been triggered by solar forcing despite the absence of a 1,470-year solar cycle."
<ref name="Braun et al. 2005"> Holger Braun, Marcus Christl, Stefan Rahmstorf, Andrey Ganopolski, Augusto Mangini, Claudia Kubatzki, Kurt Roth and Bernd Kromer (2005): ''Possible solar origin of the 1,470-year glacial climate cycle demonstrated in a coupled model'', in: Nature 438, S. 208-211, 10. November, doi:10.1038/nature04121, siehe Abstract [http://www.nature.com/nature/journal/v438/n7065/abs/nature04121.html online]</ref>
Muscheler et al.[Bearbeiten]
Muscheler, Raimund, Fortunat Joos, Simon A. Müller und Ian Snowball (2005): How unusual is today’s solar activity?, in: Nature, Vol. 436, 28. Juli, S. E3-E4 (PDF)
<ref name="Muscheler et al. 2005">Muscheler, Raimund, Fortunat Joos, Simon A. Müller und Ian Snowball (2005): ''How unusual is today’s solar activity?'', in: Nature, Vol. 436, 28. Juli, S. E3-E4 [http://www.cgd.ucar.edu/ccr/raimund/publications/Muscheler_et_al_Nature2005.pdf (PDF)]</ref>
Dewitte et al.[Bearbeiten]
Dewitte S., D. Crommelynck, S. Mekaoui und A. Joukoff (2005): Measurement and uncertainty of the long-term total solar irradiance trend, in: Solar Physics, 224, S. 209-216, siehe Abstract online
"A possible long-term trend of the total solar irradiance could be a natural cause for climate variations on Earth. Measurement of the total solar irradiance with space radiometers started in 1978. We present a new total solar irradiance composite, with an uncertainty of ± 0.35 W m−2. From the minimum in 1995 to the maximum in 2002 the total solar irradiance increased by 1.6 W m−2. In between the minima of 1987 and 1995 the total solar irradiance increased by 0.15 W m−2."
<ref name="Dewitte et al. 2005">Dewitte S., D. Crommelynck, S. Mekaoui und A. Joukoff (2005): ''Measurement and uncertainty of the long-term total solar irradiance trend'', in: Solar Physics, 224, S. 209-216, siehe Abstract [http://www.springerlink.com/content/j801527210384164/ online]</ref>
Wang et al.[Bearbeiten]
Wang, Y.-M., J.L. Lean, und N.R. Sheeley, Jr. (2005): Modeling the Sun's Magnetic Field and Irradiance since 1713, in: The Astrophysical Journal, Volume 625, Issue 1, pp. 522-538, doi: 10.1086/429689, siehe Abstract online
"We use a flux transport model to simulate the evolution of the Sun's total and open magnetic flux over the last 26 solar cycles (1713-1996). Polar field reversals are maintained by varying the meridional flow speed between 11 and 20 m s-1, with the poleward-directed surface flow being slower during low-amplitude cycles. If the strengths of the active regions are fixed but their numbers are taken to be proportional to the cycle amplitude, the open flux is found to scale approximately as the square root of the cycle amplitude. However, the scaling becomes linear if the number of active regions per cycle is fixed but their average strength is taken to be proportional to the cycle amplitude. Even with the inclusion of a secularly varying ephemeral region background, the increase in the total photospheric flux between the Maunder minimum and the end of solar cycle 21 is at most ~one-third of its minimum-to-maximum variation during the latter cycle. The simulations are compared with geomagnetic activity and cosmogenic isotope records and are used to derive a new reconstruction of total solar irradiance (TSI). The increase in cycle-averaged TSI since the Maunder minimum is estimated to be ~1 W m-2. Because the diffusive decay rate accelerates as the average spacing between active regions decreases, the photospheric magnetic flux and facular brightness grow more slowly than the sunspot number and TSI saturates during the highest amplitude cycles."
Fröhlich, C., and J. Lean (2004): Solar radiative output and its variability: Evidence and mechanisms, in: Astronomy and Astrophysics Review, 12, S. 273-320, DOI: 10.1007/s00159-004-0024-1 (PDF)
"Electromagnetic radiation from the Sun is Earth’s primary energy source. Space-based radiometric measurements in the past two decades have begun to establish the nature, magnitude and origins of its variability. An 11-year cycle with peak-topeak amplitude of order 0.1 % is now well established in recent total solar irradiance observations, as are larger variations of order 0.2 % associated with the Sun’s 27-day rotation period. The ultraviolet, visible and infrared spectral regions all participate in these variations, with larger changes at shorter wavelengths. Linkages of solar radiative output variations with solar magnetism are clearly identified.Active regions alter the local radiance, and their wavelength-dependent contrasts relative to the quiet Sun control the relative spectrum of irradiance variability. Solar radiative output also responds to subsurface convection and to eruptive events on the Sun. On the shortest time scales, total irradiance exhibits five minute fluctuations of amplitude ≈ 0.003 %, and can increase to as much as 0.015 % during the very largest solar flares. Unknown is whether multidecadal changes in solar activity produce longer-term irradiance variations larger than observed thus far in the contemporary epoch. Empirical associations with solar activity proxies suggest reduced total solar irradiance during the anomalously low activity in the seventeenth century Maunder Minimum relative to the present. Uncertainties in understanding the physical relationships between direct magnetic modulation of solar radiative output and heliospheric modulation of cosmogenic proxies preclude definitive historical irradiance estimates, as yet."
<ref name="Fröhlich/Lean 2004">Fröhlich, C., and J. Lean (2004): ''Solar radiative output and its variability: Evidence and mechanisms'', in: Astronomy and Astrophysics Review, 12, S. 273-320, DOI: 10.1007/s00159-004-0024-1 [http://supernova.ist.utl.pt/~dario/artigos/Lean_2004.pdf#search=%22%22Solar%20radiative%20output%20and%20its%20variability%3A%20Evidence%20and%20mechanisms%22 (PDF)]</ref>
Solanki et al.[Bearbeiten]
Solanki, Sami, I.G. Usoskin, B. kromer, M. Schüssler und J. Beer (2004): Unusual activity of the Sun during recent decades compared to the previous 11,000 years, in: Nature, Vol. 431, 28 Oktober, S. 1084-1087 (PDF)
"Direct observations of sunspot numbers are available for the past four centuries, but longer time series are required, for example, for the identification of a possible solar influence on climate and for testing models of the solar dynamo. Here we report a reconstruction of the sunspot number covering the past 11,400 years, based on dendrochronologically dated radiocarbon concentrations. We combine physics-based models for each of the processes connecting the radiocarbon concentration with sunspot number. According to our reconstruction, the level of solar activity during the past 70 years is exceptional, and the previous period of equally high activity occurred more than 8,000 years ago.We find that during the past 11,400 years the Sun spent only of the order of 10% of the time at a similarly high level of magnetic activity and almost all of the earlier high-activity periods were shorter than the present episode. Although the rarity of the current episode of high average sunspot numbers may indicate that the Sun has contributed to the unusual climate change during the twentieth century, we point out that solar variability is unlikely to have been the dominant cause of the strong warming during the past three decades."
<ref name="Solanki et al. 2004">Solanki, Sami, I.G. Usoskin, B. kromer, M. Schüssler und J. Beer (2004): ''Unusual activity of the Sun during recent decades compared to the previous 11,000 years'', in: Nature, Vol. 431, 28 Oktober, S. 1084-1087 [http://cc.oulu.fi/%7Eusoskin/personal/nature02995.pdf (PDF)]</ref>
Damon, Paul E. (2004): Pattern of Strange Errors Plagues Solar Activity and Terrestrial Climate Data, in: Eos, Vol. 85, No. 39, S. 370, 374 (PDF)
<ref>Damon, Paul E. (2004): ''Pattern of Strange Errors Plagues Solar Activity and Terrestrial Climate Data'', in: Eos, Vol. 85, No. 39, S. 370, 374 [http://www.realclimate.org/damon&laut_2004.pdf (PDF)]</ref>
Max Planck Society[Bearbeiten]
Max Planck Society (2004): How Strongly Does the Sun Influence the Global Climate? Press Release, 2. August, siehe online
"Since the middle of the last century, the Sun is in a phase of unusually high activity, as indicated by frequent occurrences of sunspots, gas eruptions, and radiation storms. Researchers at the Max Planck Institute for Solar System Research (MPS) in Katlenburg-Lindau (Germany) and at the University of Oulu (Finland) have come to this conclusion after they have succeeded in reconstructing the solar activity based on the sunspot frequency since 850 AD. To this end, they have combined historical sunspot records with measurements of the frequency of radioactive isotopes in ice cores from Greenland and the Antarctic. As the scientists have reported in the renowned scientific journal, Physical Review Letters, since 1940 the mean sunspot number is higher than it has ever been in the last thousand years and two and a half times higher than the long term average. The temporal variation in the solar activity displays a similarity to that of the mean temperature of the Earth. These scientific results therefore bring the influence of the Sun on the terrestrial climate, and in particular its contribution to the global warming of the 20th century, into the forefront of current interest. However, researchers at the MPS have shown that the Sun can be responsible for, at most, only a small part of the warming over the last 20-30 years. They took the measured and calculated variations in the solar brightness over the last 150 years and compared them to the temperature of the Earth. Although the changes in the two values tend to follow each other for roughly the first 120 years, the Earth’s temperature has risen dramatically in the last 30 years while the solar brightness has not appreciably increased in this time."
<ref name="MPS 2004">Max Planck Society (2004): ''How Strongly Does the Sun Influence the Global Climate?'' Press Release, 2. August, siehe [http://www.mpg.de/english/illustrationsDocumentation/documentation/pressReleases/2004/pressRelease20040802/ online]</ref>
Stott et al.[Bearbeiten]
Stott, Peter A., Gareth S. Jones und John F.B. Mitchell (2003): Do Models Underestimate the Solar Contribution to Recent Climate Change? In: Journal of Climate, Volume 16, Dezember, S. 4079-4093 (PDF)
"Current attribution analyses that seek to determine the relative contributions of different forcing agents to observed near-surface temperature changes underestimate the importance of weak signals, such as that due to changes in solar irradiance. Here a new attribution method is applied that does not have a systematic bias against weak signals.
It is found that current climate models underestimate the observed climate response to solar forcing over the twentieth century as a whole, indicating that the climate system has a greater sensitivity to solar forcing than do models. The results from this research show that increases in solar irradiance are likely to have had a greater influence on global-mean temperatures in the first half of the twentieth century than the combined effects of changes in anthropogenic forcings. Nevertheless the results confirm previous analyses showing that greenhouse gas increases explain most of the global warming observed in the second half of the twentieth century."
<ref>Stott, Peter A., Gareth S. Jones und John F.B. Mitchell (2003): Do Models Underestimate the Solar Contribution to Recent Climate Change? In: Journal of Climate, Volume 16, Dezember, S. 4079-4093 [http://climate.envsci.rutgers.edu/pdf/StottEtAl.pdf (PDF)]</ref>
Solanki, S.K. und N.A. Krivova (2003): Can solar variability explain global warming since 1970?, in: Journal of Geophysical Research, Vol. 108, No. A5, 1200, doi:10.1029/2002JA009753, siehe Abstract online
"The magnitude of the Sun's influence on climate has been a subject of intense debate. Estimates of this magnitude are generally based on assumptions regarding the forcing due to solar irradiance variations and climate modeling. This approach suffers from uncertainties that are difficult to estimate. Such uncertainties are introduced because the employed models may not include important but complex processes or mechanisms or may treat these in too simplified a manner. Here we take a more empirical approach. We employ time series of the most relevant solar quantities, the total and UV irradiance between 1856 and 1999 and the cosmic rays flux between 1868 and 1999. The time series are constructed using direct measurements wherever possible and reconstructions based on models and proxies at earlier times. These time series are compared with the climate record for the period 1856 to 1970. The solar records are scaled such that statistically the solar contribution to climate is as large as possible in this period. Under this assumption we repeat the comparison but now including the period 1970–1999. This comparison shows without requiring any recourse to modeling that since roughly 1970 the solar influence on climate (through the channels considered here) cannot have been dominant. In particular, the Sun cannot have contributed more than 30% to the steep temperature increase that has taken place since then, irrespective of which of the three considered channels is the dominant one determining Sun-climate interactions: tropospheric heating caused by changes in total solar irradiance, stratospheric chemistry influenced by changes in the solar UV spectrum, or cloud coverage affected by the cosmic ray flux."
<ref name="Solanki et al. 2003">Solanki, S.K. und N.A. Krivova (2003): ''Can solar variability explain global warming since 1970?'', in: Journal of Geophysical Research, Vol. 108, No. A5, 1200, doi:10.1029/2002JA009753, siehe Abstract [http://www.agu.org/pubs/crossref/2003/2002JA009753.shtml online]</ref>
Shindell/Schmidt et al.[Bearbeiten]
Shindell, D.T., G.A. Schmidt, R.L. Miller und M.E. Mann (2003): Volcanic and solar forcing of climate change during the preindustrial era, in: Journal of Climate 16, S. 4094-4107, doi:10.1175/1520-0442(2003)016<4094:VASFOC>2.0.CO;2 (PDF)
"The climate response to variability in volcanic aerosols and solar irradiance, the primary forcings during the preindustrial era, is examined in a stratosphere-resolving general circulation model. The best agreement with historical and proxy data is obtained using both forcings, each of which has a significant effect on global mean temperatures. However, their regional climate impacts in the Northern Hemisphere are quite different. While the short-term continental winter warming response to volcanism is well-known, we show that due to opposing dynamical and radiative effects, the long-term (decadal mean) regional response is not significant compared to unforced variability for either the winter or the annual average. In contrast, the long-term regional response to solar forcing greatly exceeds unforced variability for both time-averages, as the dynamical and radiative effects reinforce one another, and produces climate anomalies similar to those seen during the Little Ice Age. Thus, long-term regional changes during the preindustrial appear to have been dominated by solar forcing."
<ref name="Shindell/Schmidt et al. 2003">Shindell, D.T., G.A. Schmidt, R.L. Miller und M.E. Mann (2003): '''Volcanic and solar forcing of climate change during the preindustrial era''', in: Journal of Climate 16, S. 4094-4107, doi:10.1175/1520-0442(2003)016<4094:VASFOC>2.0.CO;2 [http://pubs.giss.nasa.gov/docs/2003/2003_ShindellSchmidtMM.pdf (PDF)]</ref>
Schmitt, D. and M. Schüssler (2003): Klimaveräanderung – Treibhauseffekt oder Sonnenaktivität? Max-Planck-Institut für Aeronomie (PDF)
<ref name="Schmitt/Schüssler 2003">Schmitt, D. and M. Schüssler (2003): Klimaveräanderung – Treibhauseffekt oder Sonnenaktivität? Max-Planck-Institut für Aeronomie [http://www.mps.mpg.de/dokumente/publikationen/pa/pa_0301_klima.pdf (PDF)]</ref>
Lean et al.[Bearbeiten]
Lean, J.L, Y.-M. Wang und N.R. Sheeley Jr. (2002): The effect of increasing solar activity on the Sun's total and open magnetic flux during multiple cycles: Implications for solar forcing of climate, in: Geophysical Research Letters, VOl. 29, No. 24, doi: 10.1029/2002GL015880, siehe Abstract online
"We investigate the relationship between solar irradiance and cosmogenic isotope variations by simulating with a flux transport model the effect of solar activity on the Sun's total and open magnetic flux. As the total amount of magnetic flux deposited in successive cycles increases, the polar fields build up, producing a secular increase in the open flux that controls the interplanetary magnetic field which modulates the cosmic ray flux that produces cosmogenic isotopes. Non-axisymmetric fields at lower latitudes decay on time scales of less than a year; as a result the total magnetic flux at the solar surface, which controls the Sun's irradiance, lacks an upward trend during cycle minima. This suggests that secular increases in cosmogenic and geomagnetic proxies of solar activity may not necessarily imply equivalent secular trends in solar irradiance. Questions therefore arise about the interpretation of Sun-climate relationships, which typically assume that the proxies imply radiative forcing."
Laut, P und J. Gundermann (2000): Is there a correlation between solar cycle lengths and terrestrial temperatures? Old claims and new results, siehe Abstract online
"The present analysis was triggered by continuing claims in the Danish public climate debate (1) that terrestrial temperatures are almost exclusively determined by solar activity, (2) that the human influence until now has been negligible and (3) that there is no need to reduce manmade greenhouse gas emissions. To support these claims usually reference is made to the "strikingly good agreement" between solar cycle lengths and Northern Hemisphere land temperatures which was described by Friis-Christensen and Lassen (1991 and 1995) and attracted wordwide attention. We attempt to verify these claims. This question is, of course, of vital importance for national energy policies. Our present work demonstrates that an alternative analysis of the underlying physical data leads to figures that do not support the claims mentioned above."
<ref name="Laut/Gunderman 2000">Laut, P und J. Gundermann (2000): ''Is there a correlation between solar cycle lengths and terrestrial temperatures? Old claims and new results?'', siehe Abstract [http://md1.csa.com/partners/viewrecord.php?requester=gs&collection=TRD&recid=A0225479AH&q=&uid=788898035&setcookie=yes online]</ref>
P. Theyll und Frits Lassen (1999): Solar forcing of the Northern hemisphere land air temperature: New data. Danish Meteorological Institute, Scientific Report 99-9 (PDF)
"It has previously been demonstrated that the mean land air temperature of the Northern hemisphere could adequately be associated with a long-term variation of solar activity as given by the length of the approximately 11- year solar cycle. Adding new temperature data for the 1990’s and expected values for the next sunspot extrema we test whether the solar cycle length model is still adequate. We find that the residuals are now inconsistent with the pure solar model. We conclude that since around 1990 the type of Solar forcing that is described by the solar cycle length model no longer dominates the long-term variation of the Northern hemisphere land air temperature."
<ref name="Thejll/Lassen 1999">P. Theyll und Frits Lassen (1999): ''Solar forcing of the Northern hemisphere land air temperature: New data''. Danish Meteorological Institute, Scientific Report 99-9 [http://www.dmi.dk/dmi/sr99-9.pdf (PDF)]</ref>