In mountainous surfaces,land surface temperature(LST)plays a vital role in surface energy budget and vegetation-soil ecosystems.Despite advancements in retrieving LST from thermal infrared measurements at various spat...In mountainous surfaces,land surface temperature(LST)plays a vital role in surface energy budget and vegetation-soil ecosystems.Despite advancements in retrieving LST from thermal infrared measurements at various spatial and temporal scales,accurately estimating LST for complex terrain remains challenging.This challenge arises from the conflict between the topographic effect and the assumption of flatten surface in many existing studies.In the absence of a simple and practical model for the topographic effect on the directional anisotropies of LST(LSTDA)over mountainous areas,the equivalent slope method is introduced to bridge the gap between studies conducted on flat surfaces and complex terrain.The proposed thermal equivalent slope kernel-driven(TESKD)model is validated using measurements and simulations from an unmanned aerial vehicle(UAV)system and a 3-dimensional raytracing model,respectively.Results indicate the following:(a)Under varying topographic conditions,vegetation cover,and solar zenith angles,there is a significant impact of topography on LSTDA.The average effect is greater than 0.5 K and can reach up to 1.5 K at the higher solar zenith angle(50°).(b)Based on UAV data,TESKD provides a better explanation and fitting effect for LSTDA in 3 typical mountainous surfaces including valley,peak,and solo-slope,with an average root mean square error(RMSE)of 0.27 K and an average coefficient of determinations of 0.628 of the 3 conditions,compared to a flat model(0.35 K and 0.335).(c)Based on simulations,TESKD exhibits more than a 30%improvement in accuracy,and for sparsely vegetated surfaces,the difference in RMSE can be up to 0.8 K when considering the topographic effect compared to not considering it.The new model can help to understand the radiative transfer process in heterogeneous mountainous surfaces and serves as a valuable tool for studies associated with water and carbon cycles.展开更多
According to the data characteristics of Landsat thematic mapper （TM） and MODIS, a new fu sion algorithm about thermal infrared data has been proposed in the article based on improving wave let reconstruction. Under...According to the data characteristics of Landsat thematic mapper （TM） and MODIS, a new fu sion algorithm about thermal infrared data has been proposed in the article based on improving wave let reconstruction. Under the domain of neighborhood wavelet reconstruction, data of TM and MO DIS are divided into three layers using wavelet decomposition. The texture information of TM data is retained by fusing highfrequency information. The neighborhood correction coefficient method （NC CM） is set up based on the search neighborhood of a certain size to fuse lowfrequency information. Thermal infrared value of MODIS data is reduced to the space value of TM data by applying NCCM. The data with high spectrum, high spatial and high temporal resolution, are obtained through the al gorithm in the paper. Verification results show that the texture information of TM data and high spec tral information of MODIS data could be preserved well by the fusion algorithm. This article could provide technical support for high precision and fast extraction of the surface environment parame ters.展开更多
Volcanic eruption is one of the most serious geological disasters,however,a host of facts have proven that the Changbai Mountains volcano is a modern dormant one and has ever erupted disastrously. With the rapid devel...Volcanic eruption is one of the most serious geological disasters,however,a host of facts have proven that the Changbai Mountains volcano is a modern dormant one and has ever erupted disastrously. With the rapid development of remote sensing technology,space monitoring of volcanic activities has already become possible,particularly in the application of thermal infrared remote sensing. The paper,through the detailed analysis of geothermal anomaly factors such as heat radiation,heat conduction and convection,depicts the monitoring principles by which volcano activities would be monitored efficiently and effectively. Reasons for abrupt geothermal anomaly are mainly analyzed,and transmission mechanism of geothermal anomaly in the volcanic regions is explained. Also,a variety of noises disturbing the transmission of normal geothermal anomaly are presented. Finally,some clues are given based on discussing thermal infrared remote sensing monitoring mechanism toward the volcanic areas.展开更多
The components of urban surface cover are diversified,and component temperature has greater physical significance and application values in the studies on urban thermal environment.Although the multi-angle retrieval a...The components of urban surface cover are diversified,and component temperature has greater physical significance and application values in the studies on urban thermal environment.Although the multi-angle retrieval algorithm of component temperature has been matured gradually,its application in the studies on urban thermal environment is restricted due to the difficulty in acquiring urban-scale multi-angle thermal infrared data.Therefore,based on the existing multi-source multi-band remote sensing data,access to appropriate urban-scale component temperature is an urgent issue to be solved in current studies on urban thermal infrared remote sensing.Then,a retrieval algorithm of urban component temperature by multi-source multi-band remote sensing data on the basis of MODIS and Landsat TM images was proposed with expectations achieved in this work,which was finally validated by the experiment on urban images of Changsha,China.The results show that：1） Mean temperatures of impervious surface components and vegetation components are the maximum and minimum,respectively,which are in accordance with the distribution laws of actual surface temperature; 2） High-accuracy retrieval results are obtained in vegetation component temperature.Moreover,through a contrast between retrieval results and measured data,it is found that the retrieval temperature of impervious surface component has the maximum deviation from measured temperature and its deviation is greater than 1 ℃,while the deviation in vegetation component temperature is relatively low at 0.5 ℃.展开更多
Aiming at two Dayao earthquakes with magnitude more than 6 occurred in 2003 in Yunnan Province, we analyzed and interpreted the NOAA satellite thermal infrared images of 1999, 2003 and 2004 in Chuandian region, and al...Aiming at two Dayao earthquakes with magnitude more than 6 occurred in 2003 in Yunnan Province, we analyzed and interpreted the NOAA satellite thermal infrared images of 1999, 2003 and 2004 in Chuandian region, and also calculated the annual variation of brightness temperature of the hot belt along Honghe fault to explore the formation cause of the high temperature belt and its relation to the earthquakes. The results show that the high temperature belt along Honghe fault is caused by geographic environment factors, such as water system and terrain. But the annual average brightness temperature of the belt in earthquake year of 2003 is clearly higher than that in no earthquake years of 1999 and 2004, this maybe indicates that the thermal activities of Honghe fault increase in earthquake years, and can cause the annual variation anomaly of brightness temperature. We can detect and monitor this thermal activities of Honghe fault before earthquake by analyzing and comparing the relative changes of thermal infrared brightness temperature of the hot belt in different years.展开更多
The calefacient phenomenon in the vicinity of the epicenter before an earthquake has observed. It shows that ther exists some abnormal information of heat radiation in the seismogenic zone. It might be helpful to open...The calefacient phenomenon in the vicinity of the epicenter before an earthquake has observed. It shows that ther exists some abnormal information of heat radiation in the seismogenic zone. It might be helpful to open up a new research field of survey the hot omen of earthquake and to improve the capability of earthquake prediction by using the satellite remote sensing technology.展开更多
MODerate resolution atmospheric TRANsmission(MODTRAN)is a commercial remote sensing(RS)software package that has been widely used to simulate radiative transfer of electromagnetic radiation through the Earth’s atmosp...MODerate resolution atmospheric TRANsmission(MODTRAN)is a commercial remote sensing(RS)software package that has been widely used to simulate radiative transfer of electromagnetic radiation through the Earth’s atmosphere and the radiation observed by a remote sensor.However,when very large RS datasets must be processed in simulation applications at a global scale,it is extremely time-consuming to operate MODTRAN on a modern workstation.Under this circumstance,the use of parallel cluster computing to speed up the process becomes vital to this time-consuming task.This paper presents PMODTRAN,an implementation of a parallel task-scheduling algorithm based on MODTRAN.PMODTRAN was able to reduce the processing time of the test cases used here from over 4.4 months on a workstation to less than a week on a local computer cluster.In addition,PMODTRAN can distribute tasks with different levels of granularity and has some extra features,such as dynamic load balancing and parameter checking.展开更多
The Large Field of View Airborne Infrared Scanner is a newly developed multi-spectral instrument that collects images from the near-infrared to long-wave infrared channels.Its data can be used for land surface tempera...The Large Field of View Airborne Infrared Scanner is a newly developed multi-spectral instrument that collects images from the near-infrared to long-wave infrared channels.Its data can be used for land surface temperature(LST)retrieval and environmental monitoring.Before data application,quality assessment is an essential procedure for a new instrument.In this paper,based on the data collected by the scanner near the Yellow River in Henan Province,the geometric and radiometric qualities of the images are first evaluated.The absolute geolocation accuracy of the ten bands of the scanner is approximately 5.1 m.The ground sampling distance is found to be varied with the whisk angles of the scanner and the spatial resolution of the images.The band-to-band registration accuracy between band one and the other nine bands is approximately 0.25 m.The length and angle deformations of the ten bands are approximately 0.67%and 0.3°,respectively.The signal-to-noise ratio(SNR)and relative radiometric calibration accuracy of bands 4,9,and 10 are relatively better than those of the other bands.Secondly,the radiative transfer equation(RTE)method is used to retrieve the LST from the data of the scanner.Measurements of in situ samples are collected to evaluate the retrieved LST.Neglecting the samples with unreasonable retrieved LST,the bias and RMSE between in situ LST measured by CE312 radiometer and retrieved LST are−0.22 K and 0.94 K,and the bias and RMSE are 0.27 K and 1.59 K for the InfReC R500-D thermal imager,respectively.Overall,the images of the Large Field of View Airborne Infrared Scanner yield a relatively satisfactory accuracy for both LST retrieval and geometric and radiometric qualities.展开更多
基金supported in part by the Chinese Natural Science Foundation Project(42130111,42271362,2020YFA0608703,and 41930111).
文摘In mountainous surfaces,land surface temperature(LST)plays a vital role in surface energy budget and vegetation-soil ecosystems.Despite advancements in retrieving LST from thermal infrared measurements at various spatial and temporal scales,accurately estimating LST for complex terrain remains challenging.This challenge arises from the conflict between the topographic effect and the assumption of flatten surface in many existing studies.In the absence of a simple and practical model for the topographic effect on the directional anisotropies of LST(LSTDA)over mountainous areas,the equivalent slope method is introduced to bridge the gap between studies conducted on flat surfaces and complex terrain.The proposed thermal equivalent slope kernel-driven(TESKD)model is validated using measurements and simulations from an unmanned aerial vehicle(UAV)system and a 3-dimensional raytracing model,respectively.Results indicate the following:(a)Under varying topographic conditions,vegetation cover,and solar zenith angles,there is a significant impact of topography on LSTDA.The average effect is greater than 0.5 K and can reach up to 1.5 K at the higher solar zenith angle(50°).(b)Based on UAV data,TESKD provides a better explanation and fitting effect for LSTDA in 3 typical mountainous surfaces including valley,peak,and solo-slope,with an average root mean square error(RMSE)of 0.27 K and an average coefficient of determinations of 0.628 of the 3 conditions,compared to a flat model(0.35 K and 0.335).(c)Based on simulations,TESKD exhibits more than a 30%improvement in accuracy,and for sparsely vegetated surfaces,the difference in RMSE can be up to 0.8 K when considering the topographic effect compared to not considering it.The new model can help to understand the radiative transfer process in heterogeneous mountainous surfaces and serves as a valuable tool for studies associated with water and carbon cycles.
基金Supported by the National Natural Science Foundation of China(No.41101503)the National Social Science Foundation of China(No.11&ZD161)Graduate Innovative Scientific Research Project of Chongqing Technology and Business University(No.yjscxx2014-052-29)
文摘According to the data characteristics of Landsat thematic mapper （TM） and MODIS, a new fu sion algorithm about thermal infrared data has been proposed in the article based on improving wave let reconstruction. Under the domain of neighborhood wavelet reconstruction, data of TM and MO DIS are divided into three layers using wavelet decomposition. The texture information of TM data is retained by fusing highfrequency information. The neighborhood correction coefficient method （NC CM） is set up based on the search neighborhood of a certain size to fuse lowfrequency information. Thermal infrared value of MODIS data is reduced to the space value of TM data by applying NCCM. The data with high spectrum, high spatial and high temporal resolution, are obtained through the al gorithm in the paper. Verification results show that the texture information of TM data and high spec tral information of MODIS data could be preserved well by the fusion algorithm. This article could provide technical support for high precision and fast extraction of the surface environment parame ters.
文摘Volcanic eruption is one of the most serious geological disasters,however,a host of facts have proven that the Changbai Mountains volcano is a modern dormant one and has ever erupted disastrously. With the rapid development of remote sensing technology,space monitoring of volcanic activities has already become possible,particularly in the application of thermal infrared remote sensing. The paper,through the detailed analysis of geothermal anomaly factors such as heat radiation,heat conduction and convection,depicts the monitoring principles by which volcano activities would be monitored efficiently and effectively. Reasons for abrupt geothermal anomaly are mainly analyzed,and transmission mechanism of geothermal anomaly in the volcanic regions is explained. Also,a variety of noises disturbing the transmission of normal geothermal anomaly are presented. Finally,some clues are given based on discussing thermal infrared remote sensing monitoring mechanism toward the volcanic areas.
基金Projects(41171326,40771198)supported by the National Natural Science Foundation of ChinaProject(08JJ6023)supported by the Natural Science Foundation of Hunan Province,China
文摘The components of urban surface cover are diversified,and component temperature has greater physical significance and application values in the studies on urban thermal environment.Although the multi-angle retrieval algorithm of component temperature has been matured gradually,its application in the studies on urban thermal environment is restricted due to the difficulty in acquiring urban-scale multi-angle thermal infrared data.Therefore,based on the existing multi-source multi-band remote sensing data,access to appropriate urban-scale component temperature is an urgent issue to be solved in current studies on urban thermal infrared remote sensing.Then,a retrieval algorithm of urban component temperature by multi-source multi-band remote sensing data on the basis of MODIS and Landsat TM images was proposed with expectations achieved in this work,which was finally validated by the experiment on urban images of Changsha,China.The results show that：1） Mean temperatures of impervious surface components and vegetation components are the maximum and minimum,respectively,which are in accordance with the distribution laws of actual surface temperature; 2） High-accuracy retrieval results are obtained in vegetation component temperature.Moreover,through a contrast between retrieval results and measured data,it is found that the retrieval temperature of impervious surface component has the maximum deviation from measured temperature and its deviation is greater than 1 ℃,while the deviation in vegetation component temperature is relatively low at 0.5 ℃.
基金National Natural Science Foundation of China (90202018).
文摘Aiming at two Dayao earthquakes with magnitude more than 6 occurred in 2003 in Yunnan Province, we analyzed and interpreted the NOAA satellite thermal infrared images of 1999, 2003 and 2004 in Chuandian region, and also calculated the annual variation of brightness temperature of the hot belt along Honghe fault to explore the formation cause of the high temperature belt and its relation to the earthquakes. The results show that the high temperature belt along Honghe fault is caused by geographic environment factors, such as water system and terrain. But the annual average brightness temperature of the belt in earthquake year of 2003 is clearly higher than that in no earthquake years of 1999 and 2004, this maybe indicates that the thermal activities of Honghe fault increase in earthquake years, and can cause the annual variation anomaly of brightness temperature. We can detect and monitor this thermal activities of Honghe fault before earthquake by analyzing and comparing the relative changes of thermal infrared brightness temperature of the hot belt in different years.
文摘The calefacient phenomenon in the vicinity of the epicenter before an earthquake has observed. It shows that ther exists some abnormal information of heat radiation in the seismogenic zone. It might be helpful to open up a new research field of survey the hot omen of earthquake and to improve the capability of earthquake prediction by using the satellite remote sensing technology.
基金This work was mainly supported by the National High-Technology Research and Development Program(863)[grant number 2013AA122801]the National Science Foundation of the United States[Award No.1251095]+3 种基金Also it was partially supported by the Fundamental Research Funds for the Central Universities[grant number ZYGX2015J111]the project entitled‘Design and development of the parallelism for typical remote sensing image algorithm based on heterogeneous computing’from the Institute of Remote Sensing and Digital Earth,Chinese Academy of Sciencesthe project entitled‘CAST Innovation Fund:the Study of Agent and Cloud Based Spatial Big Data Service Chain’also the National Natural Science Foundation of China[grant number 51277167].
文摘MODerate resolution atmospheric TRANsmission(MODTRAN)is a commercial remote sensing(RS)software package that has been widely used to simulate radiative transfer of electromagnetic radiation through the Earth’s atmosphere and the radiation observed by a remote sensor.However,when very large RS datasets must be processed in simulation applications at a global scale,it is extremely time-consuming to operate MODTRAN on a modern workstation.Under this circumstance,the use of parallel cluster computing to speed up the process becomes vital to this time-consuming task.This paper presents PMODTRAN,an implementation of a parallel task-scheduling algorithm based on MODTRAN.PMODTRAN was able to reduce the processing time of the test cases used here from over 4.4 months on a workstation to less than a week on a local computer cluster.In addition,PMODTRAN can distribute tasks with different levels of granularity and has some extra features,such as dynamic load balancing and parameter checking.
基金supported by the National Natural Science Foundation of China(Grant Nos.42171363,41804166,and 41971299)High-Resolution Earth Observation Major Special Aviation Observation System(No.30-H30C01-9004-19/21)+1 种基金the Shanghai Municipal Science and Technology Major Project(No.2021SHZDZX0100)the Shanghai Municipal Commission of Science and Technology Project(No.19511132101).
文摘The Large Field of View Airborne Infrared Scanner is a newly developed multi-spectral instrument that collects images from the near-infrared to long-wave infrared channels.Its data can be used for land surface temperature(LST)retrieval and environmental monitoring.Before data application,quality assessment is an essential procedure for a new instrument.In this paper,based on the data collected by the scanner near the Yellow River in Henan Province,the geometric and radiometric qualities of the images are first evaluated.The absolute geolocation accuracy of the ten bands of the scanner is approximately 5.1 m.The ground sampling distance is found to be varied with the whisk angles of the scanner and the spatial resolution of the images.The band-to-band registration accuracy between band one and the other nine bands is approximately 0.25 m.The length and angle deformations of the ten bands are approximately 0.67%and 0.3°,respectively.The signal-to-noise ratio(SNR)and relative radiometric calibration accuracy of bands 4,9,and 10 are relatively better than those of the other bands.Secondly,the radiative transfer equation(RTE)method is used to retrieve the LST from the data of the scanner.Measurements of in situ samples are collected to evaluate the retrieved LST.Neglecting the samples with unreasonable retrieved LST,the bias and RMSE between in situ LST measured by CE312 radiometer and retrieved LST are−0.22 K and 0.94 K,and the bias and RMSE are 0.27 K and 1.59 K for the InfReC R500-D thermal imager,respectively.Overall,the images of the Large Field of View Airborne Infrared Scanner yield a relatively satisfactory accuracy for both LST retrieval and geometric and radiometric qualities.
