STUDY ON TRANSMISSION MECHANISM OF THERMAL INFRARED REMOTE SENSING FOR ABRUPT GEOTHERMAL ANOMALY IN VOLCANIC REGION

Experiment researches have proven that there is an obvious phenomenon of abrupt geothermal anomaly in volcanic region in the forewarning period of volcano eruption, which is closely related to the geological structure, the cause, the scale and the type of volcano etc. On the other hand, this kind of geothermal anomaly is an important sign to monitor volcano activity by thermal infrared remote sensing techniques. This paper discusses the feature of abrupt geothermal anomaly, the transmission mechanism of geothermal anomaly and the radiation transmission mechanism of heat field of terrene in volcanic region. By analyzing mechanism of terrene temperature rising by way of conduction and convection of heat, we have presented the transmission equation of atmosphere for thermal infrared radiation based on the effective radiation of objects. The related problems of noise interference in the processes of transmission for thermal infrared radiation will be discussed in the later paper.

Improving wavelet reconstruction algorithm to achieve comprehensive application of thermal infrared remote sensing data from TM and MODIS

According to the data characteristics of Landsat thematic mapper(TM) and MODIS,a new fusion algorithm about thermal infrared data has been proposed in the article based on improving wavelet reconstruction.Under the domain of neighborhood wavelet reconstruction,data of TM and MODIS are divided into three layers using wavelet decomposition.The texture infonnation of TM data is retained by fusing high-frequency information.The neighborhood correction coefficient method(NCCM) is set up based on the search neighborhood of a certain size to fuse low-frequency 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 algorithm in the paper.Verification results show that the texture information of TM data and high spectral 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 parameters.

Interpreting the Shortwave Infrared &Thermal Infrared Regions of Remote Sensed Electromagnetic Spectrum with Application for Mineral-Deposits Exploration

The ASTER (Advanced Space-borne Thermal Emission and Reflection radiometer) data, including all the 3 parts: VNIR (Visible and Near-Infrared), SWIR (Short Wave Infrared), TIR (Thermal Infrared), were applied for extraction of mineral deposits, such as the Ni-Cu deposit in eastern Tianshan, the gypsum in western Tianshan, and the borax in Tibetan. This paper discusses the extraction methodology using the ASTER remote sensing data and reveals the good extraction results. This paper bravely represents the summary of the main achievement for this field by the scientists in other countries and gives a comparison with the works by others. The new achievements, described in this paper, comprise the extraction of anomalies for Ni-Cu deposit, gypsum, and borax.

Retrieval of urban land surface component temperature using multi-source remote-sensing data

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°C.

FRAME DESIGN OF REMOTE SENSING MONITORINGFOR VOLCANIC ACTIVITIES IN CHANGBAI MOUNTAINS

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.

Research on the Estimation Model of Soil Moisture Content Based on the Characteristics of Thermal Infrared Data

With the portable Fourier Transform Infrared Spectroscopy (FTIR), the reflectance spectra of soil samples with different moisture content are measured in laboratory for expounding the characteristic of radiation in the thermal infrared part of the spectrum with different soil moisture content. A model of estimating the moisture content in soil is attempted to make based on Moisture Diagnostic Index (MDI). In general,the spectral characteristic of soil emissivity in laboratory includes the following aspects.Firstly,in the region of 8.0-9.5 μm,along with the increase of soil moisture content,the emissivity of soil increases to varying degrees. The spectral curves are parallel relatively and have a tendency to become horizontal and the absorbed characteristic of reststrahlen is also weakened relatively with the increase of soil moisture in this region.Secondly,in the region of 11.0-14.0 μm,the emissivity of soil has a tendency of increasing.There is an absorption value near about 12.7 μm. As the soil moisture content increases,the depth of absorption also increases. This phenomenon may be caused by soil moisture absorption. Methods as derivative, difference and standardized ratio transformation may weaken the background noise effectively to the spectrum data. Especially using the ratio of the emissivity to the average of 8-14 μm may obviously enhance the correlation between soil moisture and soil emissivity. According to the result of correlation analysis, the 8.237 μm is regarded as the best detecting band for soil moisture content. Moreover,based on the Moisture Diagnostic Index ( MDI) in the 8.194-8.279 μm, the logarithmic model of estimating soil moisture is made.

INFRARED THERMAL IMAGE STUDY ON THE FOREWARNING OF COAL AND SANDSTONE FAILURE UNDER LOAD

In the experimental study, AGE-782 thermal instrument was used to detect the infrared radiation variation of coal and sandstone (wave-length range 3.6～5.5 μm was used). It's discovered that coal and sandstone failure under load have three kinds of infrared thermal features as well as infrared forewarning messages. That are: (1) temperature rises gradually but drops before failure ; (2) temperature rises gradually but quickly rises before failure; (3) first rises,then drops and lower temperature emerges before failure. The further researches and the prospect of micro-wave remote sensing detection .on ground pressure is also discussed.

Formation cause of thermal infrared high temperature belt along Honghe fault and its relation to earthquakes

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.

Analysis of Thermal Infrared Anomalies for the April16,2013M_W7.8of Khash, Iran Earthquake

After using the "Time-Frequency Relative Power Spectrum"( T-F RPS) method based on the China Geostationary Meteorological Satellite( FY-2 C/FY-2 E) infrared remote sensing brightness temperature data processing,we rapidly and accurately extracted and identified pre-earthquake thermal infrared anomalies for the April 16,2013 MW7. 8 of Khash,Iran Earthquake. Spatial evolution of anomalies showed the distribution and process. The anomalies were mainly distributed in the east of Khash,Iran. The characteristics of process and distribution presented X-Type model of NE and near NS strip which relates to the geological structure of this region. The epicenter was located near the intersection region of the X-Type abnormal migration process. Besides,the results of time series of anomalies showed that,the duration was more than 40 days and the maximum amplitude was about18 times. The earthquake occurred 20 days after the abnormal maximum amplitude which appeared on March 26,2013.

Genetic inverse algorithm for retrieval of component temperature of mixed pixel by multi-angle thermal infrared remote sensing data

After carefully studying the results of retrieval of land surface temperature(LST) by multi-channel thermal infrared remote sensing data, the authors of this paper point out that its accuracy and significance for applications are seriously damaged by the high correlation coefficient among multi-channel information and its disablement of direct retrieval of component temperature. Based on the model of directional radiation of non-isothermal mixed pixel, the authors point out that multi-angle thermal infrared remote sensing can offer the possibility to directly retrieve component temperature, but it is also a multi-parameter synchronous inverse problem. The results of digital simulation and field experiments show that the genetic inverse algorithm (GIA) is an effective method to fulfill multi-parameter synchronous retrieval. So it is possible to realize retrieval of component temperature with error less than 1K by multi-angle thermal infrared remote sensing data and GIA.

An experiment using mid and thermal infrared in quantum remote sensing

The concept of quantum remote sensing and the differences between quantum remote sensing and remote sensing is introduced, an experiment about the uses of mid and thermal infrared in quantum remote sensing is described and results are analyzed.

New Remote Sensing Method of Prospecting for Petroleum Zone of Enrichment--Exploration-serving Technique of Satellite Thermal Infrared Band

From the theoretical point of view, the gas and oil enrichment zone continuously emanates gases to the earth surface.This geochemical component anomaly has been observed by people in their earth surface survey.In 1953 R. L. Fleisher and L. G.

Study on thermal infrared remote sensing of Yarlung Zangbo River and Bangong Co-Nujiang River suture belt in Qinghai-Tibet Plateau

The area change of heat abnormity is not in accordance with conclusions of former thermal infrared remote sensing studies of the Qinghai-Tibet Plateau, which were that the temperature of Yarlung Zangbo River suture belt of the southern Plateau is high and the northern temperature is low. The study result in this paper shows that the highest temperature is found in the Bangong Co-Nujiang River suture belt, the Yarlung Zangbo River suture belt temperature is the second highest, and the northern Tibet temperature is the lowest. The study demonstration area was the suture belt areas of the Yarlung Zangbo River and the Bangong Co-Nujiang River in the Qinghai-Tibet Plateau, where the land temperature of the Qinghai-Tibet Plateau and the bore temperature of field land surface were measured and the emissivity of land surface was calculated. In addition, the authors explore the mechanism of the relationship between thermal infrared remote sensing and constructing thermodynamics and reach four new conclusions about the thermodynamics of the Tibet Plateau.

Application of satellite thermal infrared remote sensing in monitoring magmatic activity of Changbaishan Tianchi volcano

In this paper, with the application of satellite thermal infrared remote sensing technique, nine land surface temperature distribution maps of Changbaishan Tianchi volcano area are retrieved from nine thermal infrared images which are taken from 1999 to 2008. In terms of NDVI (Normalized Difference Vegetation Index), we classify the surface cover of the study area into three types, i.e. vegetation (forest), mixture of soil and vegetation (short grasses), and bare rock. The average temperature of each type of surface covers is calculated first, and then the average daily temperature record from Tianchi meteorological station is subtracted in order to reduce the effect of weather variation. Finally, thermal anomalies of three types of surface cover in Changbaishan Tianchi vol-cano area in the period of 1999 to 2008 are obtained, which is believed to reflect the magmatic activity in the magma chamber under Tianchi volcano caldera. Our results indicate that temperature of the study area increased with an intermittent tendency during 1999 to 2005, but dropped after 2005, and then maintained a relatively stable state from 2006 to 2008. Such a tendency of annual temperature variation possibly caused by magmatic activity is correlated with the results observed by means of seismic monitoring, ground deformation from GPS measurement, and volcanic gas geochemistry monitoring in the same area. It is im-plied that the upward intrusion of magma may cause temperature increase, and such temperature variation is great enough so that could be detected by using satellite thermal infrared remote sensing technology.

基于多时相热红外遥感的理塘盆地地热资源探测

地热能是地球内部一种环保、可再生的地下热能,热量传导至地表会引起地表温度异常。然而,地表温度受到太阳辐射、周期性变化和降水等诸多因素的影响,可能掩盖由地热引起的温度异常。为了解决这些问题并突出地热引起的地表温度异常,文中提出了一种利用Google Earth Engine(GEE)高效快速计算多时相冬季平均地表温度并提取地热异常的方法,并对理塘盆地的地热资源分布特征进行了研究。该方法综合运用多时相冬季平均地表温度对比分析、水体剔除、地形效应抑制等手段来提取地热异常区。结果表明,文中确定的8处地热异常区与断裂构造关系密切,且区内水资源丰富,具备地热资源形成的良好条件,可以作为未来地热勘探的重点方向。研究认为,在高原恶劣环境中,利用多时相平均冬季地表温度识别地热异常是一种高效且经济的方法。

2023年积石山6.2级地震热红外异常研究

应用卫星遥感数据,采用相对功率谱法和均线差值振幅增强比法,提取甘肃积石山6.2级地震前的热红外信息。结果表明,震前存在显著的热红外异常现象。相对功率谱法提取到的热红外异常现象分为两个阶段:(1)在2023年10月以托莱山断裂和冷龙岭断裂交汇处为核心区,出现了沿北东向展布的热红外异常(功率谱最高值超过8);(2)在2023年11月,冷龙岭断裂和金强河断裂交汇处至日月山断裂和拉脊山断裂交汇处出现了较弱的热红外异常(功率谱最高值不到7),异常的空间演化逐步向震中靠近。均线差值振幅增强比法的计算结果显示出背景性异常的特征,9月在祁连山中东至甘东南段出现了显著的长波辐射异常,两种热红外异常提取方法的结果起到了互相佐证的作用。

RESEARCH ON DISTURBED MECHANISM OF THERMAL NOISES OF THE SURFACE IN ABRUPT GEOTHERMAL ANOMALY

Geothermal anomaly as a physical phenomenon of an active and latent volca nic area would be well recog-nized,and abrupt geothermal anomaly should also be understood.However,in practical work,thermal infrare d remote sensing techniques are frequently u sed to monitor geothermal flows of th e earth.But then,except for this typ e of thermal source in the surface thermal field,there still exist a lot of noises in th e area where the abrupt geothermal an omaly is generat-ed.By Analyzing the reason,we find t hat it is brought about by the non-bou ndless projection characteristics of objects.These noises may be divided into two c lasses:system noises and random noises.If disturbed noises have comparative sta-ble time sequence law and space sequence law,the noises are called system noises.And because system noises have a certain law,it is easy to remove the n oises.On the contrary,if disturbed noises have not law of time sequence a nd space sequence,the noises are called random noises.The random noises have the character of non-linearity,uncertainty and indeterminism.For this case,this p aper discusses the disturbed mechan ism of these noises as well as how to re move them..

PMODTRAN:a parallel implementation based on MODTRAN for massive remote sensing data processing

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.

光照与阴影对无人机热红外遥感监测土壤含水率的影响

为探究作物冠层受阳光直射或阴影遮挡对无人机热红外遥感诊断作物水分胁迫、监测土壤含水率的影响,该研究以不同灌溉处理的夏玉米为研究对象,将热红外图像划分为光照冠层、阴影冠层、光照土壤、阴影土壤4个部分,分别提取光照温度与阴影温度后计算了11:00、13:00、15:00的冠气温差(冠层温度与大气温度之差,ΔT)、作物水分胁迫指数(crop water stress index,CWSI)、蒸发比(潜热通量与有效能量的比值,evaporative fraction,EF),并对比了3种指数在不同时刻使用光照温度(ΔT_(L)、CWSI_(L)、EF_(L))与阴影温度(ΔT_(S)、CWSI_(S)、EF_(S))后对土壤含水率的监测效果变化情况。结果表明:1)3种指数的监测效果会随时间发生变化,11:00与15:00时EF监测效果较好,13:00时CWSI监测效果较好,ΔT的监测效果较差但随时间波动最小;2)拔节期在区分光照温度与阴影温度后监测效果在11:00时提升幅度最大,EF、EF_(S)、EF_(L)的R^(2)分别为0.54、0.65、0.78,CWSI、CWSI_(S)、CWSI_(L)的R^(2)分别为0.47、0.64、0.70,抽雄期与灌浆期使用光照温度对监测效果提升不大,但使用阴影温度的指数监测效果有明显降低,在13:00时CWSIS较CWSI有最大降幅,R^(2)降幅分别为0.11、0.06;3)在拔节期与抽雄期使用11:00的EFL,在灌浆期使用13:00的CWSI能取得最好的土壤含水率监测效果,验证期预测土壤含水率的R2分别为0.75、0.75、0.89。该研究可以为无人机热红外监测土壤含水率提供参考。

全球地表热辐射特性数据集构建技术研究

红外遥感成像主要采集地表热辐射特性,具有观测对象动态范围广、能量时空变化度高等特点。为实现高像质、高效率的红外遥感观测,迫切需要研究全球地表热辐射特性的时空分布规律,形成卫星总体设计的重要先验知识库,用于指导卫星面向观测数据质量的智能化设计。针对现有的全球地表热辐射数据集时空覆盖率较低、缺值较严重的问题,文章基于多源卫星遥感数据,通过遥感数据融合技术,构建较为完备的全球地表热辐射数据集,为星上空间相机最佳成像参数自主选取提供有力支撑。