Experimental estimation of the local energy balance of the potential-confining electrons in tandem-mirror plasmas

2006 ◽  
Vol 77 (10) ◽  
pp. 10F302
Author(s):  
T. Numakura ◽  
T. Cho ◽  
J. Kohagura ◽  
M. Hirata ◽  
R. Minami ◽  
...  
Keyword(s):  
Energy Balance ◽  
Local Energy ◽  
Tandem Mirror ◽  
Experimental Estimation

Evaluating and Improving Parameterizations of the Variance of Temperature Fluctuations Over Heterogeneous Landscapes for Surface Boundary Conditions in Atmospheric Models

2021 ◽  
Author(s):  
Tyler Waterman ◽  
Gabriel Katul ◽  
Andy Bragg ◽  
Nathaniel Chaney
Keyword(s):  
Energy Balance ◽  
Boundary Conditions ◽  
Weather Prediction ◽  
Potential Temperature ◽  
Temperature Fluctuations ◽  
Higher Order ◽  
Parameterization Scheme ◽  
Surface Boundary ◽  
Local Energy ◽  
Temperature Variance

<p>The implementation of higher-order turbulence closure schemes in Earth system models (e.g., the Cloud Layers Unified by Binormals; CLUBB) aims to improve the modeling of convection and radiative transfer in numerical weather prediction and climate models. However, the added value of these schemes is constrained by the specification of boundary conditions on higher-order statistics. At the land surface, many of the higher order turbulence statistics that are required as boundary conditions are parameterized using formulations more appropriate for stationary and planar-homogeneous flow in the absence of subsidence. A case in point is the variance of the potential temperature fluctuations.  Because of the additive nature of variances arising from non-uniformity in surface heating, current parameterizations are not readily generalizable. The current scheme used in CLUBB, as well as other models, relies on limited studies over uniform terrain, with the variance entirely determined by local sensible heat flux, friction velocity, and the Obukhov stability parameter without regard to local site characteristics. This presentation aims to address this weakness by leveraging the National Ecological Observation Network (NEON) network of eddy covariance towers to validate the current parameterization scheme for potential temperature variance, as well as propose improvements for more heterogeneous terrain.</p><p>The turbulence fluctuations of temperature at 39 NEON sites are processed and quality controlled, removing points occurring at night, while precipitation is falling, and with sub-zero temperatures. Results overall indicate the current scheme performs well, especially over flat homogeneous terrain where local flux relationships dominate. When there is sufficiently heterogeneous, rough terrain or non-closure of the local energy balance, however, existing schemes fail to accurately estimate the variances in temperature. In these cases, the parameterization needs to be modified, and initial results suggest simple adjustments can yield improvements and reduce error close to that of the uniform sites with local energy balance closure. The successful improvement of the temperature variance parameterization scheme implies high potential for similar, new, empirically derived parameterizations for the surface boundaries for other higher order turbulent statistics (e.g. temperature skewness) in atmospheric turbulence models.</p>

scholarly journals Measurements of the local energy balance over a coral reef flat, Heron Island, southern Great Barrier Reef, Australia

2010 ◽  
Vol 115 (D19) ◽  
Author(s):  
Hamish A. McGowan ◽  
Andrew P. Sturman ◽  
Melissa C. MacKellar ◽  
Andrew H. Wiebe ◽  
David T. Neil
Keyword(s):  
Coral Reef ◽  
Energy Balance ◽  
Great Barrier Reef ◽  
Reef Flat ◽  
Local Energy ◽  
Barrier Reef

Local Energy Balance

2013 ◽  
pp. 119-138 ◽  
Author(s):  
Pierre Kastendeuch
Keyword(s):  
Energy Balance ◽  
Local Energy

Analysis of the energy balance of the local energy supply system based on the bioenergy complex

2020 ◽  
Author(s):  
Qawaqzeh Mohamed ◽  
Alexander Lazurenko ◽  
Alexander Miroshnyk ◽  
Serhii Dudnikov ◽  
Alexander Savchenko ◽  
...  
Keyword(s):  
Energy Balance ◽  
Energy Supply ◽  
Supply System ◽  
Local Energy ◽  
Energy Supply System

scholarly journals Bjerknes Compensation in Meridional Heat Transport under Freshwater Forcing and the Role of Climate Feedback

2017 ◽  
Vol 30 (14) ◽  
pp. 5167-5185 ◽  
Author(s):  
Haijun Yang ◽  
Qin Wen ◽  
Jie Yao ◽  
Yuxing Wang
Keyword(s):  
Energy Balance ◽  
Heat Transport ◽  
Meridional Overturning Circulation ◽  
Hadley Cell ◽  
Climate Feedback ◽  
Local Energy ◽  
Surface Temperature Change ◽  
Local Climate ◽  
Freshwater Forcing ◽  
The Tropics

Using a coupled Earth climate model, freshwater forcing experiments are performed to study the Bjerknes compensation (BJC) between meridional atmosphere heat transport (AHT) and meridional ocean heat transport (OHT). Freshwater hosing in the North Atlantic weakens the Atlantic meridional overturning circulation (AMOC) and thus reduces the northward OHT in the Atlantic significantly, leading to a cooling (warming) in the surface layer in the Northern (Southern) Hemisphere. This results in an enhanced Hadley cell and northward AHT. Meanwhile, the OHT in the Indo-Pacific is increased in response to the Hadley cell change, partially offsetting the reduced OHT in the Atlantic. Two compensations occur here: compensation between the AHT and the Atlantic OHT, and that between the Indo-Pacific OHT and the Atlantic OHT. The AHT change undercompensates the OHT change by about 60% in the extratropics, while the former overcompensates the latter by about 30% in the tropics due to the Indo-Pacific change. The BJC can be understood from the viewpoint of large-scale circulation change. However, the intrinsic mechanism of BJC is related to the climate feedback of the Earth system. The authors’ coupled model experiments confirm that the occurrence of BJC is an intrinsic requirement of local energy balance, and local climate feedback determines the extent of BJC, consistent with previous theoretical results. Even during the transient period of climate change, the BJC is well established when the ocean heat storage is slowly varying and its change is much weaker than the net local heat flux change at the ocean surface. The BJC can be deduced from the local climate feedback. Under the freshwater forcing, the overcompensation in the tropics is mainly caused by the positive longwave feedback related to clouds, and the undercompensation in the extratropics is due to the negative longwave feedback related to surface temperature change. Different dominant feedbacks determine different BJC scenarios in different regions, which are in essence constrained by local energy balance.

Magnetohydrodynamic wave propagation and local energy balance

1992 ◽  
Vol 45 (6) ◽  
pp. 3962-3971
Author(s):  
Klaus Elsässer ◽  
Hamid Saleem
Keyword(s):  
Wave Propagation ◽  
Energy Balance ◽  
Local Energy ◽  
Magnetohydrodynamic Wave

Effects of Ambipolar Diffusion on Prominence Thread Models

1994 ◽  
Vol 144 ◽  
pp. 315-321 ◽  
Author(s):  
M. G. Rovira ◽  
J. M. Fontenla ◽  
J.-C. Vial ◽  
P. Gouttebroze
Keyword(s):  
Energy Balance ◽  
Transition Region ◽  
Ambipolar Diffusion ◽  
Line Profiles ◽  
Balance Equations ◽  
Model Calculations ◽  
Partial Frequency ◽  
Frequency Redistribution ◽  
Partial Frequency Redistribution ◽  
Theoretical Structure

AbstractWe have improved previous model calculations of the prominence-corona transition region including the effect of the ambipolar diffusion in the statistical equilibrium and energy balance equations. We show its influence on the different parameters that characterize the resulting prominence theoretical structure. We take into account the effect of the partial frequency redistribution (PRD) in the line profiles and total intensities calculations.

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