Klaus Fraedrich

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Power-law scaling of near surface air temperature fluctuations and its geographical distribution is analyzed in 100-yr observations and in a 1000-yr simulation of the present-day climate with a complex atmosphere-ocean model. In observations and simulation detrended fluctuation analysis leads to the scaling exponent alpha approximately 1 over the oceans,(More)
Many applications in the evaluation of climate impacts and environmental policy require detailed spatiotemporal projections of future climate. To capture feedbacks from impacted natural or socio-economic systems requires interactive two-way coupling, but this is generally computationally infeasible with even moderately complex general circulation models(More)
The ability of analysing atmospheric dynamics by idealized experiments using a simplified circulation model is illustrated in three related studies. The investigations focus on the organization of localized strom tracks, their impact on low-frequency variability, and on the response to external thermal forcing. A localized storm track in agreement with(More)
[1] Boundary layer turbulence plays a central role in determining the strength of the overall atmospheric circulation by affecting the intensity of exchange of heat, mass, and momentum at the Earth’s surface. It is often parameterized using the bulk formula, in which the vonKarman parameter plays a critical role. Here we conducted a range of sensitivity(More)
The impact of mountains and ice sheets on the large-scale circulation of the world’s oceans is investigated in a series of simulations with a new coupled ocean–atmosphere model [Oregon State University–University of Victoria model (OSUVic)], in which the height of orography is scaled from 1.5 times the actual height (at T42 resolution) to 0 (no mountains).(More)
[1] The low frequency variability of the near surface temperature in a climate simulation is compared with Greenland ice core dO time series during the holocene. The simulation is performed with the coupled CSIRO atmosphere-ocean model under present-day conditions. The variability, analyzed by the detrended fluctuation analysis, reveals power-law scaling of(More)
Valerio Lucarini,a,b,c* Klaus Fraedrichd and Frank Lunkeitd aDepartment of Meteorology, University of Reading, UK bDepartment of Mathematics, University of Reading, UK cDepartment of Physics, University of Bologna, Italy dMeteorologisches Institut, KlimaCampus, University of Hamburg, Germany *Correspondence to: Valerio Lucarini, Department of Meteorology,(More)
A general circulation model of the Martian Atmosphere is coupled with a 3-dimensional polythermal ice-sheet model of the polar ice caps. With this combination a series of experiments is carried out to investigate the impact of long-term obliquity change on the Martian north polar ice cap (NPC). The behaviour of the NPC is tested under obliquities of y 1⁄4(More)