Magnetic Instabilities in Stellar Atmospheres [PDF]
International Astronomical Union Colloquium, 1983 ABSTRACT.The extensive theory for magnetohydrodynamic instability of a flux tube is briefly reviewed, together with its application to tokamaks and solar flares. In a star a single coronal loop whose footprints are anchored in the dense photosphere may become unstable to the kink instability when it is twisted too much.
openaire +1 more source
Climate Change Increases the Potential for Extreme Wildfires
Geophysical Research Letters, 2019 Pyrocumulonimbus (pyroCb) wildfires cause devastation in many regions globally. Given that fire‐atmosphere coupling is associated with pyroCbs, future changes in coincident high index values of atmospheric instability and dryness (C‐Haines) and near ...
Giovanni Di Virgilio +6 more
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Radiative levitation: a likely explanation for pulsations in the unique hot O subdwarf star SDSS J160043.6+074802.9 [PDF]
, 2008 Context. SDSS J160043.6+074802.9 (J1600+0748 for short) is the only hot sdO star for which unambiguous multiperiodic luminosity variations have been reported so far.
Andersen, M. +6 more
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Nature Communications, 2020 Machine learning has been used to represent small-scale processes, such as clouds, in atmospheric models but this can lead to instability in simulations of climate.
Janni Yuval, Paul A. O’Gorman
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Filamentational Instability of Partially Coherent Femtosecond Optical Pulses in Air
, 2006 The filamentational instability of spatially broadband femtosecond optical pulses in air is investigated by means of a kinetic wave equation for spatially incoherent photons.
Bergé +21 more
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Spectroscopic analysis of DA white dwarfs with 3D model atmospheres [PDF]
, 2013 We present the first grid of mean three-dimensional (3D) spectra for pure-hydrogen (DA) white dwarfs based on 3D model atmospheres. We use CO5BOLD radiation-hydrodynamics 3D simulations instead of the mixing-length theory for the treatment of convection.
Freytag, B. +3 more
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Enhancing the fire weather index with atmospheric instability information
Environmental Research Letters, 2020 The Fire Weather Index (FWI) is widely used to assess the meteorological fire danger in several ecosystems worldwide. One shortcoming of the FWI is that only surface weather conditions are considered, despite the important role often played by ...
Miguel M Pinto +4 more
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A Climatology of the Tropospheric Thermal Stratification Using Saturation Potential Vorticity [PDF]
, 2007 The condition of convective neutrality is assessed in the troposphere by calculating the saturation potential vorticity P* from reanalysis data. Regions of the atmosphere in which saturation entropy is constant along isosurfaces of absolute angular ...
Korty, Robert L., Schneider, Tapio
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Accelerating the spin-up of the coupled carbon and nitrogen cycle model in CLM4 [PDF]
Geoscientific Model Development, 2015 The commonly adopted biogeochemistry spin-up process in an Earth system model (ESM) is to run the model for hundreds to thousands of years subject to periodic atmospheric forcing to reach dynamic steady state of the carbon–nitrogen (CN) models. A variety
Y. Fang, C. Liu, L. R. Leung
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Self-Organization of Atmospheric Macroturbulence into Critical States of Weak Nonlinear Eddy–Eddy Interactions [PDF]
, 2006 It is generally held that atmospheric macroturbulence can be strongly nonlinear. Yet weakly nonlinear models successfully account for scales and structures of baroclinic eddies in Earth's atmosphere.
Schneider, Tapio, Walker, Christopher C.
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