Prominence condensation and magnetic levitation in a coronal loop     

G. Van Hoven  Y. Mok  J. F. Drake 《Solar physics》1992,140(2):269-287

We describe the results of a model dynamic simulation of the formation and support of a narrow prominence at the apex of a coronal magnetic loop or arcade. The condensation process proceeds via an initial radiative cooling and pressure drop, and a secondary siphon flow from the dense chromospheric ends. The anti-buoyancy effect as the prominence forms causes a bending of the confining magnetic field, which propagates toward the semi-rigid ends of the magnetic loop. Thus, a wide magnetic hammock or well (of the normal-polarity Kippenhahn-Schlüter-type) is formed, which supports the prominence at or near the field apex. The simplicity of this 1.5-dimensional model, with its accompanying diagnostics, allows one to comprehend the various contributions to the nonlinear dynamics of prominence condensation and levitation.  相似文献   

The relevance of the ballooning approximation for magnetic,thermal, and coalesced magnetothermal instabilities     

R. A. M. Van der Linden  M. Goossens  A. W. Hood 《Solar physics》1992,140(2):317-342

Approximate solutions of the linearized non-adiabatic MHD equations, obtained using the ballooning method, are compared with exact numerical solutions of the full equations (including the effects of optically thin plasma radiation). It is shown that the standard ballooning method, developed within the framework of ideal linear MHD, can be generalized to non-ideal linear MHD. The localized (ballooning) spectrum has to be used with caution, but can give valuable (though limited) information on non-ideal stability.The numerical analysis also confirms and quantifies the interesting connection between magnetic and thermal instabilities. The existence of such a coupling is inherent in many qualitative discussions of magnetic disruptions. Finally, the hitherto unrecognized role of the thermal continuum in the unstable part of the magnetothermal spectrum is investigated.Research Assistant of the National Fund for Scientific Research, Belgium.  相似文献   

REDD+ politics in the media: a case from Nepal     

Dil B. Khatri  Thuy Thu Pham  Monica Di Gregorio  Rahul Karki  Naya S. Paudel  Maria Brockhaus  Ramesh Bhushal 《Climatic change》2016,138(1-2):309-323

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How climate metrics affect global mitigation strategies and costs: a multi-model study     

Mathijs J. H. M. Harmsen  Maarten van den Berg  Volker Krey  Gunnar Luderer  Adriana Marcucci  Jessica Strefler  Detlef P. Van Vuuren 《Climatic change》2016,135(2):203-209

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How well can a convection-permitting climate model reproduce decadal statistics of precipitation,temperature and cloud characteristics?     

Erwan Brisson  Kwinten Van Weverberg  Matthias Demuzere  Annemarie Devis  Sajjad Saeed  Martin Stengel  Nicole P. M. van Lipzig 《Climate Dynamics》2016,47(9-10):3043-3061

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Extreme air–sea interaction over the North Atlantic subpolar gyre during the winter of 2013–2014 and its sub-surface legacy     

Jeremy P. Grist  Simon A. Josey  Zoe L. Jacobs  Robert Marsh  Bablu Sinha  Erik Van Sebille 《Climate Dynamics》2016,46(11-12):4027-4045

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Green growth and climate change: conceptual and empirical considerations     

Miklós Antal  Jeroen C.J.M. Van Den Bergh 《Climate Policy》2016,16(2):165-177

The feasibility of green growth is studied in the context of climate change. As carbon emissions are easier to quantify than many other types of environmental pressure, it will be possible to reach a more definite conclusion about the likelihood of green growth than has been possible in the long-standing historical debate on growth versus the environment. We calculate the rate of decoupling between gross domestic product (GDP) and GHG emissions needed to achieve internationally agreed climate targets. Next, eight arguments are considered that together suggest that fast decoupling will be very difficult. Subsequently, we examine the main lines of research used by proponents of green growth to support their viewpoint, including theoretical arguments, exercises with integrated assessment models, and studies of the environmental Kuznets curve hypothesis. It will be concluded that decoupling as a main or single strategy to combine economic and environmental aims should be judged as taking a very large risk with our common future. To minimize this risk we need to seriously consider reducing our dependence on growth. This requires a fundamental change of focus in both economic research and policy.

Policy relevance

Currently, green growth is the only strategy of mainstream economists and policy makers to address climate change. This article demonstrates that such an exclusive focus is very risky due to the scale of the challenge and the existence of various barriers to the fast decoupling of GHG emissions from economic output. It seems that the only option to combine environmental and economic objectives is reducing the dependence of our economies on growth. Finding strategies in line with this requires a fundamental change of focus in both economic research and policy.  相似文献   

Optimized strategy for the calibration of superconducting gravimeters at the one per mille level     

Michel Van Camp  Bruno Meurers  Olivier de Viron  Thomas Forbriger 《Journal of Geodesy》2016,90(1):91-99

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High-resolution simulations for Vietnam - methodology and evaluation of current climate     

Jack Katzfey  Kim Nguyen  John McGregor  Peter Hoffmann  Suppiah Ramasamy  Hiep Van Nguyen  Mai Van Khiem  Thang Van Nguyen  Kien Ba Truong  Thang Van Vu  Hien Thuan Nguyen  Tran Thuc  Doan Ha Phong  Bang Thanh Nguyen  Tan Phan-Van  Trung Nguyen-Quang  Thanh Ngo-Duc  Long Trinh-Tuan 《Asia-Pacific Journal of Atmospheric Sciences》2016,52(2):91-106

To assist the government of Vietnam in its efforts to better understand the impacts of climate change and prioritise its adaptation measures, dynamically downscaled climate change projections were produced across Vietnam. Two Regional Climate Models (RCMs) were used: CSIRO’s variable-resolution Conformal-Cubic Atmospheric Model (CCAM) and the limited-area model Regional Climate Model system version 4.2 (RegCM4.2). First, global CCAM simulations were completed using bias- and variance-corrected sea surface temperatures as well as sea ice concentrations from six Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate models. This approach is different from other downscaling approaches as it does not use any atmospheric fields from the GCMs. The global CCAM simulations were then further downscaled to 10 km using CCAM and to 20 km using RegCM4.2. Evaluations of temperature and precipitation for the current climate (1980-2000) were completed using station data as well as various gridded observational datasets. The RCMs were able to reproduce reasonably well most of the important characteristics of observed spatial patterns and annual cycles of temperature. Average and minimum temperatures were well simulated (biases generally less than 1oC), while maximum temperatures had biases of around 1oC. For precipitation, although the RCMs captured the annual cycle, RegCM4.2 was too dry in Oct.-Nov. (-60% bias), while CCAM was too wet in Dec.- Mar. (130% bias). Both models were too dry in summer and too wet in winter (especially in northern Vietnam). The ability of the ensemble simulations to capture current climate increases confidence in the simulations of future climate.  相似文献   

Vertical fault systems in the tectonosphere geoelectrical section in petroliferous domains of Sakhalin Island (Russia) and Gulf of Tonkin (Vietnam): Evidence from magnetotelluric sounding     

V. M. Nikiforov  G. N. Shkabarnya  A. Yu. Zhukovin  V. B. Kaplun  N. A. Palshin  I. M. Varentsov  Do Huy Cuong  Phung Van Phach  Hoang Van Vuong  S. S. Starzhinsky 《Russian Journal of Pacific Geology》2016,10(6):395-407

The transverse current anomalies evident from magnetotelluric sounding (MTS) data in the transition zone from the Asian continent to the Pacific Ocean and a geoelectrical model suitable for explaining these effects are discussed. Using simulation results and new MTS data on Sakhalin and northern Vietnam, ultra-deep fluid–fault system (UDFFS) models are constructed, comprising steeply dipping low-resistivity and high-resistivity linear bodies which penetrate through the whole section of the lithosphere, continuing deep into the asthenosphere. The structure of these systems reflects the development of deep and ultra-deep fault zones, along which mantle-originated fluids may migrate through sediments to reach the surface. This allows the anisotropic–conductive fractured structures adjacent to these faults to be considered as being most favorable for hydrocarbon accumulations.  相似文献