scholarly journals Reply to “Comments on ‘Global and Regional Entropy Production by Radiation Estimated from Satellite Observations’”

2021 ◽  
Vol 34 (9) ◽  
pp. 3729-3731
Author(s):  
Seiji Kato ◽  
Fred G. Rose
Keyword(s):  
Entropy Production ◽  
Energy Input ◽  
Satellite Observations ◽  
Balance Model ◽  
Irreversible Processes ◽  
Entropy Production Rate ◽  
Radiative Processes ◽  
Primary Contribution ◽  
State Assumption ◽  
Production Change

AbstractThis reply addresses a comment on the study by Kato and Rose (herein referred to as KR2020). The comment raises four points of criticism. These are 1) on notations used, 2) on a steady-state assumption made, 3) on the result of entropy production change with Earth’s albedo, and 4) disputing the statement that a simple energy balance model cannot produce absorption temperature change with Earth’s albedo. We concur on points 2 and 3 raised by the comment and recognize the significance of entropy storage due to ocean heating in the analysis of how entropy production changes with the shortwave absorptivity of Earth. Once entropy storage is considered, the results of KR2020 indicate that the increase of entropy production rate by irreversible processes, including by radiative processes, is smaller than the increase of entropy storage when absorptivity is increased. This is a manifestation of the primary contribution of positive top-of-atmosphere net irradiances (i.e., energy input to Earth) to heating the ocean and is consistent with an energy budget perspective. Once entropy storage is separated, the entropy production by irreversible processes increases with the shortwave absorptivity.

scholarly journals Between Waves and Diffusion: Paradoxical Entropy Production in an Exceptional Regime

Entropy ◽  
2018 ◽  
Vol 20 (11) ◽  
pp. 881 ◽  
Author(s):  
Karl Hoffmann ◽  
Kathrin Kulmus ◽  
Christopher Essex ◽  
Janett Prehl
Keyword(s):  
Entropy Production ◽  
Production Rate ◽  
Fractional Diffusion ◽  
Diffusion Equations ◽  
Irreversible Processes ◽  
Entropy Production Rate ◽  
Continuous Space ◽  
One Dimensional ◽  
Fractional Diffusion Equations ◽  
And Diffusion

The entropy production rate is a well established measure for the extent of irreversibility in a process. For irreversible processes, one thus usually expects that the entropy production rate approaches zero in the reversible limit. Fractional diffusion equations provide a fascinating testbed for that intuition in that they build a bridge connecting the fully irreversible diffusion equation with the fully reversible wave equation by a one-parameter family of processes. The entropy production paradox describes the very non-intuitive increase of the entropy production rate as that bridge is passed from irreversible diffusion to reversible waves. This paradox has been established for time- and space-fractional diffusion equations on one-dimensional continuous space and for the Shannon, Tsallis and Renyi entropies. After a brief review of the known results, we generalize it to time-fractional diffusion on a finite chain of points described by a fractional master equation.

A Criteria for Size Separation Using Maximum Entropy Production

2009 ◽  
Author(s):  
Chuan-ping Liu ◽  
Li Wang ◽  
Min Jia ◽  
Lige Tong
Keyword(s):  
Entropy Production ◽  
Maximum Entropy ◽  
Stable State ◽  
Irreversible Processes ◽  
Entropy Production Rate ◽  
Absolute Maximum ◽  
Kinetic Temperature ◽  
Granular Mixture ◽  
Maximum Entropy Production ◽  
Size Separation

In order to study analytically the nature of the size separation in granular mixture, we present the maximum entropy production principle based on kinetic temperature of granular mixture. For simplicity we apply this principle to size separation of a sphere binary mixture in vibrated bed, and we find a new thermodynamic mechanism of size separation phenomenon. With the irreversible processes such as elastic collisions and frictions, the kinetic energy is dissipated rapidly in system, which induces the entropy production. By the fact that the entropy production rate always has the absolute maximum at the stable state of granular mixture, we find the crossover from “Brazil Nut Effect” to its reverse by changing particles size and density, and our result is about satisfied with Schnautz’s experiment.

scholarly journals Comprehensive Criteria for the Extrema in Entropy Production Rate for Heat Transfer in the Linear Region of Extended Thermodynamics Framework

Axioms ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 113
Author(s):  
George D. Verros
Keyword(s):  
Heat Transfer ◽  
Entropy Production ◽  
Production Rate ◽  
Time Derivative ◽  
Local Heat Transfer ◽  
Extended Thermodynamics ◽  
Irreversible Processes ◽  
Entropy Production Rate ◽  
Transfer Coefficients ◽  
Linear Region

In this work comprehensive criteria for detecting the extrema in entropy production rate for heat transfer by conduction in a uniform body under a constant volume in the linear region of Extended Thermodynamics Framework are developed. These criteria are based on calculating the time derivative of entropy production rate with the aid of well-established engineering principles, such as the local heat transfer coefficients. By using these coefficients, the temperature gradient is replaced by the difference of this quantity. It is believed that the result of this work could be used to further elucidate irreversible processes.

scholarly journals Global and Regional Entropy Production by Radiation Estimated from Satellite Observations

2020 ◽  
Vol 33 (8) ◽  
pp. 2985-3000 ◽  
Author(s):  
Seiji Kato ◽  
Fred G. Rose
Keyword(s):  
Entropy Production ◽  
Longwave Radiation ◽  
Shortwave Radiation ◽  
Irreversible Processes ◽  
Earth System ◽  
Cloud Properties ◽  
The Earth ◽  
Planetary Albedo ◽  
State Assumption ◽  
Humidity Profiles

AbstractVertical profiles of shortwave and longwave irradiances computed with satellite-derived cloud properties and temperature and humidity profiles from reanalysis are used to estimate entropy production. Entropy production by shortwave radiation is computed by the absorbed irradiance within layers in the atmosphere and by the surface divided by their temperatures. Similarly, entropy production by longwave radiation is computed by emitted irradiance to space from layers in the atmosphere and surface divided by their temperatures. Global annual mean entropy production by shortwave absorption and longwave emission to space are, respectively, 0.852 and 0.928 W m−2 K−1. With a steady-state assumption, entropy production by irreversible processes within the Earth system is estimated to be 0.076 W m−2 K−1 and by nonradiative irreversible processes to be 0.049 W m−2 K−1. Both global annual mean entropy productions by shortwave absorption and longwave emission to space increase with increasing shortwave absorption (i.e., with decreasing the planetary albedo). The increase of entropy production by shortwave absorption is, however, larger than the increase of entropy production by longwave emission to space. The result implies that global annual mean entropy production by irreversible processes decreases with increasing shortwave absorption. Input and output temperatures derived by dividing the absorbed shortwave irradiance and emitted longwave irradiance to space by respective entropy production are, respectively, 282 and 259 K, which give the Carnot efficiency of the Earth system of 8.5%.

scholarly journals Comments on “Global and Regional Entropy Production by Radiation Estimated from Satellite Observations”

2021 ◽  
Vol 34 (9) ◽  
pp. 3721-3728
Author(s):  
Goodwin Gibbins ◽  
Joanna D. Haigh
Keyword(s):  
Entropy Production ◽  
Balance Model ◽  
Entropy Production Rate ◽  
Solar Absorption ◽  
Transfer Processes ◽  
Global Rate ◽  
The Mean ◽  
Convective Model ◽  
Conceptual Relationship ◽  
Nonradiative Processes

AbstractA recent paper by Kato and Rose reports a negative correlation between the annual mean entropy production rate of the climate and the absorption of solar radiation in the CERES SYN1deg dataset, using the simplifying assumption that the system is steady in time. It is shown here, however, that when the nonsteady interannual storage of entropy is accounted for, the dataset instead implies a positive correlation; that is, global entropy production rates increase with solar absorption. Furthermore, this increase is consistent with the response demonstrated by an energy balance model and a radiative–convective model. To motivate this updated analysis, a detailed discussion of the conceptual relationship between entropy production, entropy storage, and entropy flows is provided. The storage-corrected estimate for the mean global rate of entropy production in the CERES dataset from all irreversible transfer processes is 81.9 mW m−2 K−1 and from only nonradiative processes is 55.2 mW m−2 K−1 (observations from March 2000 to February 2018).

scholarly journals Entropy Production Rates of the Climate

2020 ◽  
Vol 77 (10) ◽  
pp. 3551-3566
Author(s):  
Goodwin Gibbins ◽  
Joanna D. Haigh
Keyword(s):  
Entropy Production ◽  
Production Rate ◽  
Climate Changes ◽  
Climate System ◽  
Transfer Entropy ◽  
Irreversible Processes ◽  
Solar Radiation Management ◽  
Entropy Production Rate ◽  
Production Rates ◽  
Radiation Management

AbstractThere is ongoing interest in the global entropy production rate as a climate diagnostic and predictor, but progress has been limited by ambiguities in its definition; different conceptual boundaries of the climate system give rise to different internal production rates. Three viable options are described, estimated, and investigated here, two—the material and the total radiative (here “planetary”) entropy production rates—that are well established and a third that has only recently been considered but appears very promising. This new option is labeled the “transfer” entropy production rate and includes all irreversible processes that transfer heat within the climate, radiative, and material, but not those involved in the exchange of radiation with space. Estimates in three model climates put the material rate in the range 27–48 mW m−2 K−1, the transfer rate at 67–76 mW m−2 K−1, and the planetary rate at 1279–1312 mW m−2 K−1. The climate relevance of each rate is probed by calculating their responses to climate changes in a simple radiative–convective model. An increased greenhouse effect causes a significant increase in the material and transfer entropy production rates but has no direct impact on the planetary rate. When the same surface temperature increase is forced by changing the albedo instead, the material and transfer entropy production rates increase less dramatically and the planetary rate also registers an increase. This is pertinent to solar radiation management as it demonstrates the difficulty of reversing greenhouse gas–mediated climate changes by albedo alterations. It is argued that the transfer perspective has particular significance in the climate system and warrants increased prominence.

The mechanics of granitoid systems and maximum entropy production rates

2010 ◽  
Vol 368 (1910) ◽  
pp. 53-93 ◽  
Author(s):  
Bruce E. Hobbs ◽  
Alison Ord
Keyword(s):  
Entropy Production ◽  
Maximum Entropy ◽  
Melt Inclusions ◽  
Selection Process ◽  
Finite Thickness ◽  
Control Valve ◽  
Entropy Production Rate ◽  
Constitutive Behaviour ◽  
Maximum Entropy Production ◽  
Physical Height

A model for the formation of granitoid systems is developed involving melt production spatially below a rising isotherm that defines melt initiation. Production of the melt volumes necessary to form granitoid complexes within 10 4 –10 7 years demands control of the isotherm velocity by melt advection. This velocity is one control on the melt flux generated spatially just above the melt isotherm, which is the control valve for the behaviour of the complete granitoid system. Melt transport occurs in conduits initiated as sheets or tubes comprising melt inclusions arising from Gurson–Tvergaard constitutive behaviour. Such conduits appear as leucosomes parallel to lineations and foliations, and ductile and brittle dykes. The melt flux generated at the melt isotherm controls the position of the melt solidus isotherm and hence the physical height of the Transport/Emplacement Zone. A conduit width-selection process, driven by changes in melt viscosity and constitutive behaviour, operates within the Transport Zone to progressively increase the width of apertures upwards. Melt can also be driven horizontally by gradients in topography; these horizontal fluxes can be similar in magnitude to vertical fluxes. Fluxes induced by deformation can compete with both buoyancy and topographic-driven flow over all length scales and results locally in transient ‘ponds’ of melt. Pluton emplacement is controlled by the transition in constitutive behaviour of the melt/magma from elastic–viscous at high temperatures to elastic–plastic–viscous approaching the melt solidus enabling finite thickness plutons to develop. The system involves coupled feedback processes that grow at the expense of heat supplied to the system and compete with melt advection. The result is that limits are placed on the size and time scale of the system. Optimal characteristics of the system coincide with a state of maximum entropy production rate.

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