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Basis functions for shallow-water temperature profiles based on the internal-wave eigenmodes
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作者 Qianqian Li Shoulian Cao +2 位作者 Yu Luo Kai Zhang Fanlin Yang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第2期56-64,共9页
The shallow-water temperature profile is typically parameterized using a few empirical orthogonal function(EOF)coefficients.However,when the experimental area is poorly known or highly variable,the adaptability of the... The shallow-water temperature profile is typically parameterized using a few empirical orthogonal function(EOF)coefficients.However,when the experimental area is poorly known or highly variable,the adaptability of the EOFs will be significantly reduced.In this study,a new set of basis functions,generated by combining the internal-wave eigenmodes with the average temperature gradient,is developed for characterizing the temperature perturbations.Temperature profiles recorded by a thermistor chain in the South China Sea in 2015 are processed and analyzed.Compared to the EOFs,the new set of basis functions has higher reconstruction accuracy and adaptability;it is also more stable in ocean regions that have internal waves. 展开更多
关键词 temperature profile basis function internal-wave eigenmode EOF sound speed profile
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Retrieving Atmospheric Temperature Profiles from AMSU-A Data with Neural Networks 被引量:15
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作者 姚志刚 陈洪滨 林龙福 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第4期606-616,共11页
Back propagation neural networks are used to retrieve atmospheric temperature profiles from NOAA-16 Advanced Microwave Sounding Unit-A (AMSU-A) measurements over East Asia. The collocated radiosonde observation and AM... Back propagation neural networks are used to retrieve atmospheric temperature profiles from NOAA-16 Advanced Microwave Sounding Unit-A (AMSU-A) measurements over East Asia. The collocated radiosonde observation and AMSU-A data over land in 2002-2003 are used to train the network, and the data over land in 2004 are used to test the network. A comparison with the multi-linear regression method shows that the neural network retrieval method can significantly improve the results in all weather conditions. When an offset of 0.5 K or a noise level of ±0.2 K is added to all channels simultaneously, the increase in the overall root mean square (RMS) error is less than 0.1 K. Furthermore, an experiment is conducted to investigate the effects of the window channels on the retrieval. The results indicate that the brightness temperatures of window channels can provide significantly useful information on the temperature retrieval near the surface. Additionally, the RMS errors of the profiles retrieved with the trained neural network are compared with the errors from the International Advanced TOVS (ATOVS) Processing Package (IAPP). It is shown that the network-based algorithm can provide much better results in the experiment region and comparable results in other regions. It is also noted that the network can yield remarkably better results than IAPP at the low levels and at about the 250-hPa level in summer skies over ocean. Finally, the network-based retrieval algorithm developed herein is applied in retrieving the temperature anomalies of Typhoon Rananim from AMSU-A data. 展开更多
关键词 AMSU-A neural network temperature profiles RETRIEVAL
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The Impact of AIRS Atmospheric Temperature and Moisture Profiles on Hurricane Forecasts: Ike(2008) and Irene(2011) 被引量:4
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作者 ZHENG Jing Jun LI +2 位作者 Timothy J.SCHMIT Jinlong LI Zhiquan LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第3期319-335,共17页
Atmospheric InfraRed Sounder (AIRS) measurements are a valuable supplement to current observational data,especially over the oceans where conventional data are sparse.In this study,two types of AIRS-retrieved temper... Atmospheric InfraRed Sounder (AIRS) measurements are a valuable supplement to current observational data,especially over the oceans where conventional data are sparse.In this study,two types of AIRS-retrieved temperature and moisture profiles,the AIRS Science Team product (SciSup) and the single field-of-view (SFOV) research product,were evaluated with European Centre for Medium-Range Weather Forecasts (ECMWF) analysis data over the Atlantic Ocean during Hurricane Ike (2008) and Hurricane Irene (2011).The evaluation results showed that both types of AIRS profiles agreed well with the ECMWF analysis,especially between 200 hPa and 700 hPa.The average standard deviation of both temperature profiles was approximately 1 K under 200 hPa,where the mean AIRS temperature profile from the AIRS SciSup retrievals was slightly colder than that from the AIRS SFOV retrievals.The mean SciSup moisture profile was slightly drier than that from the SFOV in the mid troposphere.A series of data assimilation and forecast experiments was then conducted with the Advanced Research version of the Weather Research and Forecasting (WRF) model and its three-dimensional variational (3DVAR) data assimilation system for hurricanes Ike and Irene.The results showed an improvement in the hurricane track due to the assimilation of AIRS clear-sky temperature profiles in the hurricane environment.In terms of total precipitable water and rainfall forecasts,the hurricane moisture environment was found to be affected by the AIRS sounding assimilation.Meanwhile,improving hurricane intensity forecasts through assimilating AIRS profiles remains a challenge for further study. 展开更多
关键词 AIRS data assimilation temperature profile moisture profile hurricane forecast WRF 3DVAR
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Estimating the Retrievability of Temperature Profiles from Satellite Infrared Measurements 被引量:3
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作者 黄静 邱崇践 +1 位作者 马刚 张艳武 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2006年第2期224-234,共11页
A method is developed to assess retrievability, namely the retrieval potential for atmospheric temperature profiles, from satellite infrared measurements in clear-sky conditions. This technique is based upon generaliz... A method is developed to assess retrievability, namely the retrieval potential for atmospheric temperature profiles, from satellite infrared measurements in clear-sky conditions. This technique is based upon generalized linear inverse theory and empirical orthogonal function analysis. Utilizing the NCEP global temperature reanalysis data in January and July from 1999 to 2003, the retrievabilities obtained with the Atmospheric Infrared Sounder (AIRS) and the High Resolution Infrared Radiation Sounder/3 (HIRS/3) sounding channel data are derived respectively for each standard pressure level on a global scale. As an incidental result of this study, the optimum truncation number in the method of generalized linear inverse is deduced too. The results show that the retrievabilities of temperature obtained with the two datasets are similar in spatial distribution and seasonal change characteristics. As for the vertical distribution, the retrievabilities are low in the upper and lower atmosphere, and high between 400 hPa and 850 hPa. For the geographical distribution, the retrievabilities are low in the low-latitude oceanic regions and in some regions in Antarctica, and relatively high in mid-high latitudes and continental regions. Compared with the HIRS/3 data, the retrievability obtained with the AIRS data can be improved by an amount between 0.15 and 0.40. 展开更多
关键词 meteorological satellites generalized linear inverses temperature profiles EOF analysis retrievability
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One-Dimensional Variational Retrieval of Temperature and Humidity Profiles from the FY4A GIIRS 被引量:4
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作者 Qiumeng XUE Li GUAN Xiaoning SHI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第3期471-486,共16页
A physical retrieval approach based on the one-dimensional variational(1 D-Var) algorithm is applied in this paper to simultaneously retrieve atmospheric temperature and humidity profiles under both clear-sky and part... A physical retrieval approach based on the one-dimensional variational(1 D-Var) algorithm is applied in this paper to simultaneously retrieve atmospheric temperature and humidity profiles under both clear-sky and partly cloudy conditions from FY-4 A GIIRS(geostationary interferometric infrared sounder) observations. Radiosonde observations from upper-air stations in China and level-2 operational products from the Chinese National Satellite Meteorological Center(NSMC)during the periods from December 2019 to January 2020(winter) and from July 2020 to August 2020(summer) are used to validate the accuracies of the retrieved temperature and humidity profiles. Comparing the 1 D-Var-retrieved profiles to radiosonde data, the accuracy of the temperature retrievals at each vertical level of the troposphere is characterized by a root mean square error(RMSE) within 2 K, except for at the bottom level of the atmosphere under clear conditions. The RMSE increases slightly for the higher atmospheric layers, owing to the lack of temperature sounding channels there.Under partly cloudy conditions, the temperature at each vertical level can be obtained, while the level-2 operational products obtain values only at altitudes above the cloud top. In addition, the accuracy of the retrieved temperature profiles is greatly improved compared with the accuracies of the operational products. For the humidity retrievals, the mean RMSEs in the troposphere in winter and summer are both within 2 g kg^(–1). Moreover, the retrievals performed better compared with the ERA5 reanalysis data between 800 h Pa and 300 h Pa both in summer and winter in terms of RMSE. 展开更多
关键词 temperature and humidity profiles one-dimensional variational(1D-Var) GIIRS hyperspectral data
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Comparisons of the temperature and humidity profiles of reanalysis products with shipboard GPS sounding measurements obtained during the 2018 Eastern Indian Ocean Open Cruise 被引量:4
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作者 WANG Lei BAO Qing +4 位作者 LI Jinxiao WANG Dongxiao LIU Yimin WU Guoxiong WU Xiaofei 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第3期177-183,共7页
It is important to be able to characterize the thermal conditions over the equatorial Indian Ocean for both weather forecasting and climate prediction. This study compared the equatorial eastern Indian Ocean (EEIO) te... It is important to be able to characterize the thermal conditions over the equatorial Indian Ocean for both weather forecasting and climate prediction. This study compared the equatorial eastern Indian Ocean (EEIO) temperature and relative humidity profiles from three reanalysis products (JRA-55, MERRA2, and FGOALS-f2) with shipboard global positioning system (GPS) sounding measurements obtained during the Eastern Indian Ocean Open Cruise in spring 2018. The FGOALS-f2 reanalysis product is based on the initialization module of a sub-seasonal to seasonal prediction system with a nudging-based data assimilation method. The results indicated that:(1) both JRA-55 and MERRA2 were reliable in characterizing the temperature profile from 850 to 600 hPa, with a maximum deviation of about <0.5℃. Both datasets showed a large negative deviation below 825 hPa, with a maximum bias of about 2℃ at 1000 hPa and 1.5℃ at 900 hPa, respectively.(2) JRA-55 showed good performance in characterizing the relative humidity profile above 850 hPa, with a maximum deviation of < 8%, while it showed much wetter conditions below 850 hPa. MERRA2 overestimated the relative humidity in the middle to lower troposphere, with a maximum deviation of about 15% at 925 hPa.(3) The FGOALS-f2 reanalysis product more accurately reproduced the temperature profile in the marine atmospheric boundary layer over the EEIO than that in JRA-55 and MERRA2, but showed much wetter conditions than the GPS sounding observations, with a maximum deviation of up to 20% at 600 hPa. Future applications of GPS sounding datasets are discussed. 展开更多
关键词 GPS sounding measurements equatorial eastern Indian Ocean temperature and humidity profiles reanalysis datasets characterization of performance
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Horizontal convection in a rectangular enclosure driven by a linear temperature profile 被引量:1
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作者 Tianyong YANG Bofu WANG +2 位作者 Jianzhao WU Zhiming LU Quan ZHOU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2021年第8期1183-1190,共8页
The horizontal convection in a square enclosure driven by a linear temperature profile along the bottom boundary is investigated numerically by using a finite difference method.The Prandtl number is fixed at 4.38,and ... The horizontal convection in a square enclosure driven by a linear temperature profile along the bottom boundary is investigated numerically by using a finite difference method.The Prandtl number is fixed at 4.38,and the Rayleigh number Ra ranges from107 to 1011.The convective flow is steady at a relatively low Rayleigh number,and no thermal plume is observed,whereas it transits to be unsteady when the Rayleigh number increases beyond the critical value.The scaling law for the Nusselt number Nu changes from Rossby’s scaling Nu~Ra^(1/5)in a steady regime to Nu~Ra^(1/4)in an unsteady regime,which agrees well with the theoretically predicted results.Accordingly,the Reynolds number Re scaling varies from Re~Ra^(3/11)to Re~Ra^(2/5).The investigation on the mean flows shows that the thermal and kinetic boundary layer thickness and the mean temperature in the bulk zone decrease with the increasing Ra.The intensity of fluctuating velocity increases with the increasing Ra. 展开更多
关键词 horizontal convection linear temperature profile turbulent heat transfer boundary layer
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The Study of In-Orbit Calibration Accuracy of NOAA Satellite Infrared Sounder and Its Effect on Temperature Profile Retrievals 被引量:1
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作者 董超华 刘全华 +1 位作者 黎光清 张凤英 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1990年第2期211-219,共9页
The calibration accuracy of High Resolution Infrared Radiation Sounder Mod. 2 (HIRS / 2) on NOAA-10 satellite is analyzed in this paper. The non-linear effect in the linear calibration curve induces a deviation of 1.5... The calibration accuracy of High Resolution Infrared Radiation Sounder Mod. 2 (HIRS / 2) on NOAA-10 satellite is analyzed in this paper. The non-linear effect in the linear calibration curve induces a deviation of 1.5 degrees (k) of brightness temperature in the tenth channel (8.3 um, water vapor absorption) of the HIRS/2 and the non-linear effect affects the other channels to a different extent. Based on analyzing non- linearity in two-point calibration curve, a tri-point calibration equation is given. A numerical test of effects of the linear and non-linear calibration models on the accuracy of atmospheric temperature retrievals is carried out. 展开更多
关键词 In The Study of In-Orbit Calibration Accuracy of NOAA Satellite Infrared Sounder and Its Effect on temperature profile Retrievals NOAA CLI
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Simulated Sensitivity of the Tropical Cyclone Eyewall Replacement Cycle to the Ambient Temperature Profile
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作者 Xulin MA Jie HE Xuyang GE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第9期1047-1056,共10页
In this study, the impacts of the environmental temperature profile on the tropical cyclone eyewall replacement cycle are examined using idealized numerical simulations. It is found that the environmental thermal cond... In this study, the impacts of the environmental temperature profile on the tropical cyclone eyewall replacement cycle are examined using idealized numerical simulations. It is found that the environmental thermal condition can greatly affect the formation and structure of a secondary eyewall and the intensity change during the eyewall replacement cycle. Simulation with a warmer thermal profile produces a larger moat and a prolonged eyewall replacement cycle. It is revealed that the enhanced static stability greatly suppresses convection, and thus causes slow secondary eyewall formation. The possible processes influencing the decay of inner eyewall convection are investigated. It is revealed that the demise of the inner eyewall is related to a choking effect associated with outer eyewall convection, the radial distribution of moist entropy fluxes within the moat region, the enhanced static stability in the inner-core region, and the interaction between the inner and outer eyewalls due to the barotropic instability. This study motivates further research into how environmental conditions influence tropical cyclone dynamics and thermodynamics. 展开更多
关键词 tropical cyclone eyewall replacement cycle ambient temperature profile
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Research on temperature profiles of honeycomb regenerator with asymptotic analysis
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作者 艾元方 《Journal of Chongqing University》 CAS 2006年第2期77-82,共6页
An asymptotic semi-analytical method for heat transfer in counter-flow honeycomb regenerator is proposed. By introducing a combined heat-transfer coefficient between the gas and solid phase, a heat transfer model is b... An asymptotic semi-analytical method for heat transfer in counter-flow honeycomb regenerator is proposed. By introducing a combined heat-transfer coefficient between the gas and solid phase, a heat transfer model is built based on the thin-walled assumption. The dimensionless thermal equation is deduced by considering solid heat conduction along the passage length. The asymptotic analysis is used for the small parameter of heat conduction term in equation. The first order asymptotic solution to temperature distribution under weak solid heat conduction is achieved after Laplace transformation through the multiple scales method and the symbolic manipulation function in MATLAB. Semi-analytical solutions agree with tests and finite-difference numerical results. It is proved possible for the asymptotic analysis to improve the effectiveness, economics and precision of thermal research on regenerator. 展开更多
关键词 honeycomb regenerator temperature profile asymptotic analysis
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Observation of Electron Temperature Profile in HL-1M Tokamak
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作者 曹建勇 徐德明 丁玄同 《Plasma Science and Technology》 SCIE EI CAS CSCD 2000年第1期87-93,共7页
In this paper, the principle and method of the electron temperature measurement by means of electron cyclotron emission (ECE) have been discribed. Several results under different conditions on HL-IM tokamak have been ... In this paper, the principle and method of the electron temperature measurement by means of electron cyclotron emission (ECE) have been discribed. Several results under different conditions on HL-IM tokamak have been given. The hollow profile of electron temperature appears in some stages, such as current rising, pellet injection and impurity concentration in the plasma centre. When the bias voltage is applied, the electron temperature profile become steeper. All of the phenomena are related with the transport in plasma centre. 展开更多
关键词 TE Observation of Electron temperature profile in HL-1M Tokamak mode HL
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A Three-Dimensional Satellite Retrieval Method for Atmospheric Temperature and Moisture Profiles
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作者 张蕾 邱崇践 黄建平 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第5期897-904,共8页
A three-dimensional variational method is proposed to simultaneously retrieve the 3-D atmospheric temperature and moisture profiles from satellite radiance measurements. To include both vertical structure and the hori... A three-dimensional variational method is proposed to simultaneously retrieve the 3-D atmospheric temperature and moisture profiles from satellite radiance measurements. To include both vertical structure and the horizontal patterns of the atmospheric temperature and moisture, an EOF technique is used to decompose the temperature and moisture field in a 3-D space. A number of numerical simulations are conducted and they demonstrate that the 3-D method is less sensitive to the observation errors compared to the 1-D method. When the observation error is more than 2.0 K, to get the best results, the truncation number for the EOF's expansion have to be restricted to 2 in the 1-D method, while it can be set as large as 40 in a 3-D method. This results in the truncation error being reduced and the retrieval accuracy being improved in the 3-D method. Compared to the 1-D method, the rms errors of the 3-D method are reduced by 48% and 36% for the temperature and moisture retrievals, respectively. Using the real satellite measured brightness temperatures at 0557 UTC 31 July 2002, the temperature and moisture profiles are retrieved over a region (20°-45°N, 100°- 125°E) and compared with 37 collocated radiosonde observations. The results show that the retrieval accuracy with a 3-D method is significantly higher than those with the 1-D method. 展开更多
关键词 atmospheric temperature and moisture profile RETRIEVAL EOF three-dimensional method satellite radiance
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Temperature Profiles of a Vertical, 7-Element Bundle Cooled with Supercritical Freon-12
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作者 Graham Richards Igor Pioro +2 位作者 Glenn Harvel Alexsei Shelegov Pavel Kirillov 《Journal of Energy and Power Engineering》 2013年第2期207-218,共12页
A set of experimental data obtained at the Institute of Physics and Power Engineering in a vertical bundle cooled with supercritical R-12 was analyzed. The test section was a 7-element bundle installed in a hexagonal ... A set of experimental data obtained at the Institute of Physics and Power Engineering in a vertical bundle cooled with supercritical R-12 was analyzed. The test section was a 7-element bundle installed in a hexagonal flow channel with three grid spacers. Data was collected at pressures of approximately 4.65 MPa for several different combinations of wall and bulk-fluid temperatures that were below, at, or above pseudocritical conditions. Analysis of the data has confirmed that there are three distinct heat-transfer regimes for forced convention in supercritical fluids: (1) normal heat transfer, (2) deteriorated heat transfer, and (3) enhanced heat transfer. It was also confirmed that the effects of spacers are evident which was previously observed in sub-critical experimental data. This work compares the wall and bulk fluid temperature data of the experiments to predictions based upon current 1-D correlations for heat transfer in supercritical fluids. 展开更多
关键词 Heat transfer fluid properties supercritical pressures Freon-12 temperature profiles.
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Temperature Profiles in the Flow Channel of a Natural Convection Solar Air Heater
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作者 K.S. Ong B.T. Tan 《Journal of Energy and Power Engineering》 2011年第2期129-134,共6页
An experimental investigation was conducted to measure the temperature variation across the flow channel and to determine the performance of a natural convection solar air heater at various tilt angles from 15, 30 and... An experimental investigation was conducted to measure the temperature variation across the flow channel and to determine the performance of a natural convection solar air heater at various tilt angles from 15, 30 and 45°. The results of the temperature profile across the air gap showed that heat transfer from the absorber plate to the air stream was mainly by convection. At a particular section, mean air temperature could be calculated from the arithmetic mean of the temperature profile across the air gap to within ± 2 ℃. The axial air temperature distribution was non linear and did not increase much beyond 1 m of collector length. It tended to decrease towards the end of the collector. Overall glass, absorber plate and mean air temperatures over the entire length of the solar air heater could be determined by averaging the mean axial temperatures to within ± 2 ℃. The heater performed better as inclination increased. 展开更多
关键词 Solar air heater natural convection inclination effects temperature profile across air gap axial temperature distribution.
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Comprehensive Examination of Solar Panel Design: A Focus on Thermal Dynamics
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作者 Kajal Sheth Dhvanil Patel 《Smart Grid and Renewable Energy》 2024年第1期15-33,共19页
In the 21st century, the deployment of ground-based Solar Photovoltaic (PV) Modules has seen exponential growth, driven by increasing demands for green, clean, and renewable energy sources. However, their usage is con... In the 21st century, the deployment of ground-based Solar Photovoltaic (PV) Modules has seen exponential growth, driven by increasing demands for green, clean, and renewable energy sources. However, their usage is constrained by certain limitations. Notably, the efficiency of solar PV modules on the ground peaks at a maximum of 25%, and there are concerns regarding their long-term reliability, with an expected lifespan of approximately 25 years without failures. This study focuses on analyzing the thermal efficiency of PV Modules. We have investigated the temperature profile of PV Modules under varying environmental conditions, such as air velocity and ambient temperature, utilizing Computational Fluid Dynamics (CFD). This analysis is crucial as the efficiency of PV Modules is significantly impacted by changes in the temperature differential relative to the environment. Furthermore, the study highlights the effect of airflow over solar panels on their temperature. It is found that a decrease in the temperature of the PV Module increases Open Circuit Voltage, underlining the importance of thermal management in optimizing solar panel performance. 展开更多
关键词 Solar Photovoltaic (PV) Modules Thermal Efficiency Analysis Open Circuit Voltage Computational Fluid Dynamics (CFD) Solar Panel temperature profile
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Vertical multiple-layer structure of temperature and turbulent diffusivity in the South China Sea 被引量:2
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作者 Xin He Changrong Liang +4 位作者 Yang Yang Guiying Chen Xiaodong Shang Xiaozhou He Penger Tong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第10期14-21,共8页
We report field measurements of vertical profiles of the turbulent diffusivity and temperature at different stations in the South China Sea(SCS).Our study shows that the measured turbulent diffusivity follows a power-... We report field measurements of vertical profiles of the turbulent diffusivity and temperature at different stations in the South China Sea(SCS).Our study shows that the measured turbulent diffusivity follows a power-law distribution with a varying exponent in water layers.Similar multiple-layer scaling regimes were also observed from the temperature fluctuations.Combining turbulent diffusivity and temperature fluctuations,the vertical structure of temperature was revealed.Furthermore,we discussed the temperature profiles in each layer.A constant function of a dimensionless temperature profile was found in water layers that have identical turbulence conditions.Our results reveal the multiple-layer structure of temperature in the SCS.This study contributes to the understanding of the vertical structure of multiple layers in the SCS and provides clues for exploring the physical mechanism for maintaining the temperature structure. 展开更多
关键词 temperature profile turbulent diffusivity South China Sea multiple layers
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A model for universal spatial variations of temperature fluctuations inturbulent Rayleigh-Bénard convection 被引量:2
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作者 Xiaozhou He Eberhard Bodenschatz Guenter Ahlers 《Theoretical & Applied Mechanics Letters》 CSCD 2021年第2期102-104,共3页
We propose a theoretical model for spatial variations of the temperature varianceσ2(z,r)(z is the dis-tance from the sample bottom and r the radial coordinate)in turbulent Rayleigh-Bénard convection(RBC).Adaptin... We propose a theoretical model for spatial variations of the temperature varianceσ2(z,r)(z is the dis-tance from the sample bottom and r the radial coordinate)in turbulent Rayleigh-Bénard convection(RBC).Adapting the“attached-eddy”modelofshearflowtothe plumesofRBC,wederivedanequationforσ2 which is based on the universal scaling of the normalized RBC temperature spectra.This equation in-cludes both logarithmic and power-law dependences on z/λth,whereλth is the thermal boundary layer thickness.The equation parameters depend on r and the Prandtl number Pr,but have only an extremelyweak dependence on the Rayleigh number Ra Thus our model provides a near-universal equation for thetemperature variance profile in turbulent RBC. 展开更多
关键词 Rayleigh-Bénard convection temperature variance profile Attached-eddy Law of wall
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Observed features of temperature, salinity and current in central Chukchi Sea during the summer of 2012 被引量:3
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作者 HE Yan LIU Na +3 位作者 CHEN Hongxia TENG Fei LIN Lina WANG Huiwu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第5期51-59,共9页
During the summer of 2012, the fifth CHINARE Arctic Expedition was carried out, and a submersible mooring system was deployed in M5 station located at (69°30.155'N,169°00.654'W) and recovered 50d later. ... During the summer of 2012, the fifth CHINARE Arctic Expedition was carried out, and a submersible mooring system was deployed in M5 station located at (69°30.155'N,169°00.654'W) and recovered 50d later. A set of temperature, salinity and current profile records was acquired. The characteristics of these observations are analyzed in this paper. Some main results are achieved as below. (1) Temperature generally decreases while salinity generally increases with increasing depth. The average values of all records are 2.98℃ and 32.21 psu. (2) Salinity and temperature are well negatively correlated, and the correlation coefficient between them is -0.84. However, they did not always vary synchronously. Their co-variation featured different characters during different significant periods. (3) The average velocity for the whole water column is 141 mm/s with directional angle of 347.1°. The statistical distribution curve of velocity record number gets narrower with increasing depth. More than 85% of the recorded velocities are northward, and the mean magnitudes of dominated northward velocities are 100-150 mm/s. (4) Rotary spectrum analysis shows that motions with low frequency take a majority of energy in all layers. The most significant energy peaks for all layers are around 0.012 cph (about 3.5 d period), while the tidal motion in mooring area is nonsignificant. (5) Velocities in all layers feature similar and synchronous temporal variations, except for the slight decrease in magnitude and leftward twist from top to bottom. The directions of velocity correspond well to those of Surface wind. The average northward volume transport per square meter is 0.1-0.2 m3/s under southerly wind, but about -0.2 m3/s during northerly wind burst. 展开更多
关键词 Chukchi Sea submersible mooring measurement 1 ong-term observations temperature and salinity velocity profile
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Spatial resolved temperature measurement based on absorption spectroscopy using a single tunable diode laser 被引量:3
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作者 Xilong Yu Fei Li Lihong Chen Xinyu Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第1期147-149,共3页
A novel method based on wavelength-multiplexed line-of-sight absorption and profile fitting for nonuniform flow field measurement is reported. A wavelength scanning combing laser temperature and current modulation WMS... A novel method based on wavelength-multiplexed line-of-sight absorption and profile fitting for nonuniform flow field measurement is reported. A wavelength scanning combing laser temperature and current modulation WMS scheme is used to implement the wavelength-multi- plexed-profile fitting method. Second harmonic (2f) signal of eight H20 transitions features near 7,170 cm^-1 are measured in one period using a single tunable diode laser. Spatial resolved temperature distribution upon a CH4/air premixed flat flame burner is obtained. The result validates the feasibility of strategy for non-uniform flow field diagnostics by means of WMS-2f TDLAS. 展开更多
关键词 WMS-2fTDLAS - profile fitting Spatial resolved - temperature measurement
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ACCURACY OF THE RETRIEVED TEMPERATURE AND HUMIDITY FIELDS FOR TYPHOON HAIYAN UTILIZING THE ADVANCED TECHNOLOGY MICROWAVE SOUNDER 被引量:1
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作者 盛文杰 刘健文 黄江平 《Journal of Tropical Meteorology》 SCIE 2017年第4期408-416,共9页
One-dimensional retrieval was performed on Typhoon Haiyan utilizing the advanced technology microwave sounder onboard the satellite Suomi NPP to retrieve the temperature and water vapor profiles of the typhoon.Compari... One-dimensional retrieval was performed on Typhoon Haiyan utilizing the advanced technology microwave sounder onboard the satellite Suomi NPP to retrieve the temperature and water vapor profiles of the typhoon.Comparisons of the retrieved profiles and ECMWF reanalysis were made to assess the results. The main conclusions are as follows.(1) The results have high spatial resolution and therefore can precisely represent the temperature and humidity distribution of the typhoon.(2) The retrieved temperature is low in the areas of low temperature and high in the areas of high temperature; similar patterns are observed for humidity. This means that systematic revision may be needed during routine application.(3) The results of the retrieved temperature and humidity profiles are generally accurate, which is quite important for typhoon monitoring. 展开更多
关键词 1-D VAR retrieving algorithm temperature and humidity profiles ATMS NPP Typhoon Haiyan
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