scholarly journals Annual Southern Ocean heat flux measured for first time

Eos ◽  
2012 ◽  
Vol 93 (44) ◽  
pp. 452-452
Author(s):  
Colin Schultz
Keyword(s):  
Heat Flux ◽  
Southern Ocean ◽  
First Time

scholarly journals Assessing Surface Heat Flux Products with In Situ Observations over the Australian Sector of the Southern Ocean

2019 ◽  
Vol 36 (9) ◽  
pp. 1849-1861
Author(s):  
Vidhi Bharti ◽  
Eric Schulz ◽  
Christopher W. Fairall ◽  
Byron W. Blomquist ◽  
Yi Huang ◽  
...  
Keyword(s):  
Heat Flux ◽  
Southern Ocean ◽  
Sensible Heat Flux ◽  
Surface Heat ◽  
Surface Fluxes ◽  
Heat Fluxes ◽  
Atmospheric Composition ◽  
Systematic Bias ◽  
Positive Bias

Given the large uncertainties in surface heat fluxes over the Southern Ocean, an assessment of fluxes obtained by European Centre for Medium-Range Weather Forecasts interim reanalysis (ERA-Interim) product, the Australian Integrated Marine Observing System (IMOS) routine observations, and the Objectively Analyzed Air–Sea Heat Fluxes (OAFlux) project hybrid dataset is performed. The surface fluxes are calculated using the COARE 3.5 bulk algorithm with in situ data obtained from the NOAA Physical Sciences Division flux system during the Clouds, Aerosols, Precipitation, Radiation, and Atmospheric Composition over the Southern Ocean (CAPRICORN) experiment on board the R/V Investigator during a voyage (March–April 2016) in the Australian sector of the Southern Ocean (43°–53°S). ERA-Interim and OAFlux data are further compared with the Southern Ocean Flux Station (SOFS) air–sea flux moored surface float deployed for a year (March 2015–April 2016) at ~46.7°S, 142°E. The results indicate that ERA-Interim (3 hourly at 0.25°) and OAFlux (daily at 1°) estimate sensible heat flux H s accurately to within ±5 W m−2 and latent heat flux H l to within ±10 W m−2. ERA-Interim gives a positive bias in H s at low latitudes (<47°S) and in H l at high latitudes (>47°S), and OAFlux displays consistently positive bias in H l at all latitudes. No systematic bias with respect to wind or rain conditions was observed. Although some differences in the bulk flux algorithms are noted, these biases can be largely attributed to the uncertainties in the observations used to derive the flux products.

scholarly journals New records of isopod species of the Antarctic Specially Managed Area No. 1, Admiralty Bay, South Shetland Islands

2017 ◽  
Vol 38 (3) ◽  
pp. 409-419
Author(s):  
Karol Zemko ◽  
Krzysztof Pabis ◽  
Jacek Siciński ◽  
Magdalena Błażewicz
Keyword(s):  
Southern Ocean ◽  
New Records ◽  
South Shetland Islands ◽  
Small Scale ◽  
King George Island ◽  
Admiralty Bay ◽  
Shetland Islands ◽  
The Antarctic ◽  
First Time ◽  
Marine Basins

AbstractAdmiralty Bay (King George Island) is an Antarctic Specially Managed Area and one the most thoroughly studied small-scale marine basins in the Southern Ocean. Our study provides new data on the isopod fauna in this glacially affected fjord. Twelve species of isopods were recorded in this basin for the first time. Six of them were found for the first time in the region of the South Shetland Islands. The highest number of species new for Admiralty Bay were found in the families Munnopsidae (4 species) and Munnidae (3 species).

A Comparison of Southern Ocean Air–Sea Buoyancy Flux from an Ocean State Estimate with Five Other Products

2011 ◽  
Vol 24 (24) ◽  
pp. 6283-6306 ◽  
Author(s):  
Ivana Cerovečki ◽  
Lynne D. Talley ◽  
Matthew R. Mazloff
Keyword(s):  
Heat Flux ◽  
Southern Ocean ◽  
Heat Loss ◽  
Large Scale ◽  
Heat Fluxes ◽  
Buoyancy Flux ◽  
Western Boundary ◽  
Turbulent Heat ◽  
Radiative Fluxes ◽  
State Estimate

Abstract The authors have intercompared the following six surface buoyancy flux estimates, averaged over the years 2005–07: two reanalyses [the recent ECMWF reanalysis (ERA-Interim; hereafter ERA), and the National Centers for Environmental Prediction (NCEP)–NCAR reanalysis 1 (hereafter NCEP1)], two recent flux products developed as an improvement of NCEP1 [the flux product by Large and Yeager and the Southern Ocean State Estimate (SOSE)], and two ad hoc air–sea flux estimates that are obtained by combining the NCEP1 or ERA net radiative fluxes with turbulent flux estimates using the Coupled Ocean–Atmosphere Response Experiment (COARE) 3.0 bulk formulas with NCEP1 or ERA input variables. The accuracy of SOSE adjustments of NCEP1 atmospheric fields (which SOSE uses as an initial guess and a constraint) was assessed by verification that SOSE reduces the biases in the NCEP1 fluxes as diagnosed by the Working Group on Air–Sea Fluxes (Taylor), suggesting that oceanic observations may be a valuable constraint to improve atmospheric variables. Compared with NCEP1, both SOSE and Large and Yeager increase the net ocean heat loss in high latitudes, decrease ocean heat loss in the subtropical Indian Ocean, decrease net evaporation in the subtropics, and decrease net precipitation in polar latitudes. The large-scale pattern of SOSE and Large and Yeager turbulent heat flux adjustment is similar, but the magnitude of SOSE adjustments is significantly larger. Their radiative heat flux adjustments patterns differ. Turbulent heat fluxes determined by combining COARE bulk formulas with NCEP1 or ERA should not be combined with unmodified NCEP1 or ERA radiative fluxes as the net ocean heat gain poleward of 25°S becomes unrealistically large. The other surface flux products (i.e., NCEP1, ERA, Large and Yeager, and SOSE) balance more closely. Overall, the statistical estimates of the differences between the various air–sea heat flux products tend to be largest in regions with strong ocean mesoscale activity such as the Antarctic Circumpolar Current and the western boundary currents.

Fundamental Roles of Nonevaporating Film and Ultrahigh Heat Flux Associated With Nanoscale Meniscus Evaporation in Nucleate Boiling

2013 ◽  
Vol 135 (6) ◽  
Author(s):  
Shalabh C. Maroo ◽  
J. N. Chung
Keyword(s):  
Heat Flux ◽  
Contact Line ◽  
Nucleate Boiling ◽  
Complex Problem ◽  
Moving Contact Line ◽  
Moving Contact ◽  
Three Phase ◽  
Dynamics Simulations ◽  
Hamaker Constants ◽  
First Time

The three-phase moving contact line present at the base of a bubble in nucleate boiling has been a widely researched topic over the past few decades. It has been traditionally divided into three regions: nonevaporating film (order of nanometers), evaporating film (order of microns), and bulk meniscus (order of millimeters). This multiscale nature of the contact line has made it a challenging and complex problem, and led to an incomplete understanding of its dynamic behavior. The evaporating film and bulk meniscus regions have been investigated rigorously through analytical, numerical and experimental means; however, studies focused on the nonevaporating film region have been very sparse. The nanometer length scale and the fluidic nature of the nonevaporating film has limited the applicability of experimental techniques, while its numerical analysis has been questionable due to the presumed continuum behavior and lack of known input parameters, such as the Hamaker constant. Thus in order to gain fundamental insights and understanding, we have used molecular dynamics simulations to study the formation and characteristics of the nonevaporating film for the first time in published literature, and outlined a technique to obtain Hamaker constants from such simulations. Further, in this review, we have shown that the nonevaporating film can exist in a metastable state of reduced/negative liquid pressures. We have also performed molecular simulations of nanoscale meniscus evaporation, and shown that the associated ultrahigh heat flux is comparable to the maximum-achievable kinetic limit of evaporation. Thus, the nonevaporating film and its adjacent nanoscale regions have a significant impact on the overall macroscale dynamics and heat flux behavior of nucleate boiling, and hence should be included in greater details in nucleate boiling simulations and analysis.

scholarly journals Time-Mean Flow as the Prevailing Contribution to the Poleward Heat Flux across the Southern Flank of the Antarctic Circumpolar Current: A Case Study in the Fawn Trough, Kerguelen Plateau

2013 ◽  
Vol 43 (3) ◽  
pp. 583-601 ◽  
Author(s):  
H. Sekma ◽  
Y.-H. Park ◽  
F. Vivier
Keyword(s):  
Heat Flux ◽  
Southern Ocean ◽  
Antarctic Circumpolar Current ◽  
Mean Flow ◽  
Kerguelen Plateau ◽  
The Mean ◽  
The Cross ◽  
Circumpolar Current ◽  
The Antarctic ◽  
Southern Flank

Abstract The major mechanisms of the oceanic poleward heat flux in the Southern Ocean are still in debate. The long-standing belief stipulates that the poleward heat flux across the Antarctic Circumpolar Current (ACC) is mainly due to mesoscale transient eddies and the cross-stream heat flux by time-mean flow is insignificant. This belief has recently been challenged by several numerical modeling studies, which stress the importance of mean flow for the meridional heat flux in the Southern Ocean. Here, this study analyzes moored current meter data obtained recently in the Fawn Trough, Kerguelen Plateau, to estimate the cross-stream heat flux caused by the time-mean flow and transient eddies. It is shown that the poleward eddy heat flux in this southern part of the ACC is negligible, while that from the mean flow is overwhelming by two orders of magnitude. This is due to the unusual anticlockwise turning of currents with decreasing depth, which is associated with significant bottom upwelling engendered by strong bottom currents flowing over the sloping topography of the trough. The circumpolar implications of these local observations are discussed in terms of the depth-integrated linear vorticity budget, which suggests that the six topographic features along the southern flank of the ACC equivalent to the Fawn Trough case would yield sufficient poleward heat flux to balance the oceanic heat loss in the subpolar region. As eddy activity on the southern flank of the ACC is too weak to transport sufficient heat poleward, the nonequivalent barotropic structure of the mean flow in several topographically constricted passages should accomplish the required task.

Application of Ambarzumian’s Method to Radiant Interchange in a Rectangular Cavity

1974 ◽  
Vol 96 (2) ◽  
pp. 191-196 ◽  
Author(s):  
A. L. Crosbie ◽  
T. R. Sawheny
Keyword(s):  
Differential Equation ◽  
Heat Flux ◽  
Integral Equation ◽  
Differential Equations ◽  
Ordinary Differential Equations ◽  
Nonlinear Integral Equation ◽  
Initial Conditions ◽  
Rectangular Cavity ◽  
Wide Range ◽  
First Time

Ambarzumian’s method had been used for the first time to solve a radiant interchange problem. A rectangular cavity is defined by two semi-infinite parallel gray surfaces which are subject to an exponentially varying heat flux, i.e., q = q0 exp(−mx). Instead of solving the integral equation for the radiosity for each value of m, solutions for all values of m are obtained simultaneously. Using Ambarzumian’s method, the integral equation for the radiosity is first transformed into an integro-differential equation and then into a system of ordinary differential equations. Initial conditions required to solve the differential equations are the H functions which represent the radiosity at the edge of the cavity for various values of m. This H function is shown to satisfy a nonlinear integral equation which is easily solved by iteration. Numerical results for the H function and radiosity distribution within the cavity are presented for a wide range of m values.

scholarly journals Экспериментальное исследование пленочного кипения недогретой воды методом градиентной теплометрии

2019 ◽  
Vol 45 (6) ◽  
pp. 10
Author(s):  
С.З. Сапожников ◽  
В.Ю. Митяков ◽  
А.В. Митяков ◽  
В.В. Субботина
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Time Distribution ◽  
Unit Area ◽  
Flux Measurement ◽  
Film Boiling ◽  
Subcooled Water ◽  
Water Based ◽  
First Time ◽  
The Relationship

AbstractThe process of subcooled water boiling is qualitatively described based on data obtained using gradient heat flux measurement. The proposed method was used for the first time for measuring the heat flux per unit area during film boiling that takes place on the endface of a cylinder submerged in subcooled water. Based on these results, the time distribution of the heat flux per unit area are constructed and the relationship between the heat flux per unit area and heat-transfer coefficient is estimated.

scholarly journals MEASURING THE PRE-HEATING TEMPERATURE OF THE PLATES SURFACE WITH IMPACT GAS IN THE WELDING GAP DURING EXPLOSION WELDING

2021 ◽  
pp. 5-11
Author(s):  
S. V. Khaustov ◽  
V. V. Pai ◽  
Ya. L. Lukyanov ◽  
S. V. Kuz’min ◽  
V. I. Lysak ◽  
...  
Keyword(s):  
Heat Flux ◽  
Satisfactory Agreement ◽  
Heating Temperature ◽  
Theoretical Calculations ◽  
Explosion Welding ◽  
Compressed Gas ◽  
Experimental Values ◽  
First Time

A technique for measuring the heat flux from the shock-compressed gas in front of the point of contact to the surface of the colliding plates has been developed. The experimental values of the heat flux are obtained, which are in satisfactory agreement with theoretical calculations. For the first time experimentally proved a significant effect of preheating of plates before collision for various materials. The effect consists in heating the surface of the plates, depending on their dimensions and properties, up to 1000 ° C and above.

scholarly journals Brief Communication: An exclusive example of surface latent heat flux variation before Russia M6.1 earthquake

2014 ◽  
Vol 2 (1) ◽  
pp. 347-359
Author(s):  
Y. Jie ◽  
G. Guangmeng
Keyword(s):  
Heat Flux ◽  
Latent Heat ◽  
Latent Heat Flux ◽  
Satellite Image ◽  
High Temporal Resolution ◽  
Flux Variation ◽  
Daily Data ◽  
Surface Latent Heat Flux ◽  
First Time ◽  
Very High

Abstract. Recently surface latent heat flux (SLHF) data is widely used to study the anomalies before earthquakes. Most researches use the daily SLHF data, here we use both daily data and high temporal resolution (four times one day) SLHF data, and compare the SLHF change with satellite image at the first time. We check the data from 1 September to 30 October 2011 and the result shows that there is really a very high SLHF anomaly (bigger than 2 σ) just 5 days before the M6.1 Russia earthquake which occurred on 14 October 2011. It should be considered as a preseismic precursor if judged with previously published methods. But our comparison between SLHF change and satellite image shows that the SLHF anomaly is just caused by a thick cloud. This result tells us that scientists must know the data's meaning before they use it, if not, they may get a wrong conclusion. Based on this example, we suggest that previously published SLHF anomaly before earthquake should be reanalyzed by our method to exclude the false anomaly.

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