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Dual-Wavelength Polarimetric Lidar Observations of the Volcanic Ash Cloud Produced during the 2016 Etna Eruption

REMOTE SENSING 2021年第9期13卷 1728-1728页

作者： Mereu, Luigi Scollo, Simona Boselli, Antonella Leto, Giuseppe Zanmar Sanchez, Ricardo Bonadonna, Costanza Marzano, Frank Silvio Sapienza Univ Rome Dept Informat Engn I-00184 Rome Italy Ctr Excellence CETEMPS I-67100 Laquila Italy Ist Nazl Geofis & Vulcanol Osservatorio Etneo I-95125 Catania Italy CNR IMAA I-85050 Potenza Italy INAF Osservatorio Astrofis I-95123 Catania Italy Univ Geneva Dept Earth Sci CH-1205 Geneva Switzerland

Lidar observations are very useful to analyse dispersed volcanic clouds in the troposphere mainly because of their high range resolution, providing morphological as well as microphysical (size and mass) properties. In this work, we analyse the volcanic cloud of 18 May 2016 at Mt. Etna, in Italy, retrieved by polarimetric dual-wavelength Lidar measurements. We use the AMPLE (Aerosol Multi-Wavelength Polarization Lidar Experiment) system, located in Catania, about 25 km from the Etna summit craters, pointing at a thin volcanic cloud layer, clearly visible and dispersed from the summit craters at the altitude between 2 and 4 km and 6 and 7 km above the sea level. Both the backscattering and linear depolarization profiles at 355 nm (UV, ultraviolet) and 532 nm (VIS, visible) wavelengths, respectively, were obtained using different angles at 20 degrees, 30 degrees, 40 degrees and 90 degrees. The proposed approach inverts the Lidar measurements with a physically based inversion methodology named Volcanic Ash Lidar retrieval (VALR), based on Maximum-Likelihood (ML). VALRML can provide estimates of volcanic ash mean size and mass concentration at a resolution of few tens of meters. We also compared those results with two methods: Single-variate Regression (SR) and Multi-variate Regression (MR). SR uses the backscattering coefficient or backscattering and depolarization coefficients of one wavelength (UV or VIS in our cases). The MR method uses the backscattering coefficient of both wavelengths (UV and VIS). In absence of in situ airborne validation data, the discrepancy among the different retrieval techniques is estimated with respect to the VALR ML algorithm. The VALR ML analysis provides ash concentrations between about 0.1 mu g/m(3) and 1 mg/m(3) and particle mean sizes of 0.1 mu m and 6 mu m, respectively. Results show that, for the SR method differences are less than <10%, using the backscattering coefficient only and backscattering and depolarization coefficients. Mo

关键词： Lidar measurements retrieval algorithms dual wavelength scanning light detection volcanic ash size and concentration

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Polarized observations for advanced atmosphere-ocean algorithms using airborne multi-spectral hyper-angular polarimetric imager

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JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER 2021年 262卷 107515-107515页

作者： El-Habashi, Ahmed Bowles, Jeffrey Foster, Robert Gray, Deric Chami, Malik Naval Res Lab Remote Sensing Div Washington DC 20375 USA CNR Washington DC 20418 USA Sorbonne Univ Lab AtmospheresMilieux Observat Spatiales LATMOS CNRS INSU Blvd ObservCS 34229 F-06304 Nice France

Airborne measurements of the linear polarization state of light were carried out over coastal and open ocean conditions to study aerosol and water column properties and investigate the possibility of using a multi-spectral, hyper-angular imaging polarimeter for retrieving aerosol and hydrosol optical properties. The instrument, the Versatile Imager for the Coastal Ocean (VICO), is used to support the analysis of ocean color polarized observations and their implication for future space-borne polarimetry such as the polarimeters planned to be deployed with the NASA Plankton, Aerosol, Cloud, and ocean Ecosystem (PACE) mission. Several sets of images at different viewing angles from the visible to the near-infrared spectrum were collected and compared with simulations using a vector radiative transfer (VRT) code. The simulations were obtained based on measured seawater inherent optical properties from shipborne instruments and measured atmospheric parameters from the Aerosol Robotic Network (AERONET) and a shipborne sunphotometer at different locations. An uncertainty method has been derived by propagating uncertainties from the measured polarized radiances. The method demonstrates practicable uncertainty formulations that can be used to construct a measurement uncertainty budget for the polarized data products. Results from VICO and the VRT simulation are consistent for both radiance and polarization spectrum at all the measured viewing angles. The total and polarized water-leaving reflectances are retrieved at four bands and varied geometries. It is also shown that the polarized remote sensing reflectance measured at various angles could be used to distinguish between the aerosols' and hydrosols' optical signatures by exploiting the fact that the polarized reflectance is fairly insensitive to hydrosols for given acquisition geometries. This study thus provides an opportunity to investigate various relationships between the microphysical properties of the oceanic and a

关键词： Vector radiative transfer Remote sensing Polarimetry VICO PACE Ocean Color retrieval algorithms Open ocean Coastal waters Scattering Bio-optics Plankton Chlorophyll-a Minerals CDOM

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Polarimetric remote sensing of atmospheric aerosols: Instruments, methodologies, results, and perspectives

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JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER 2019年 224卷 474-511页

作者： Dubovik, Oleg Li, Zhengqiang Mishchenko, Michael I. Tanre, Didier Karol, Yana Bojkov, Bojan Cairns, Brian Diner, David J. Espinosa, W. Reed Goloub, Philippe Gu, Xingfa Hasekamp, Otto Hong, Jin Hou, Weizhen Knobelspiesse, Kirk D. Landgraf, Jochen Li, Li Litvinov, Pavel Liu, Yi Lopatin, Anton Marbach, Thierry Maring, Hal Martins, Vanderlei Meijer, Yasjka Milinevsky, Gennadi Mukai, Sonoyo Parol, Frederic Qiao, Yanli Remer, Lorraine Rietjens, Jeroen Sano, Itaru Stammes, Piet Stamnes, Snorre Sun, Xiaobing Tabary, Pierre Travis, Larry D. Waquet, Fabien Xu, Feng Yan, Changxiang Yin, Dekui Univ Lille Lab Opt Atmospher CNRS Villeneuve Dascq France Chinese Acad Sci State Environm Protect Key Lab Satellite Remote S Inst Remote Sensing & Digital Earth Beijing Peoples R China NASA Goddard Inst Space Studies New York NY 10025 USA GRASP SAS Villeneuve Dascq France European Org Exploitat Meteorol Satellites EUMETS Darmstadt Germany CALTECH Jet Prop Lab Pasadena CA USA Univ Maryland Baltimore Cty Baltimore MD 21228 USA NASA Goddard Space Flight Ctr Greenbelt MD USA SRON Netherlands Inst Space Res Utrecht Netherlands Chinese Acad Sci Anhui Inst Opt & Fine Mech Hefei Anhui Peoples R China Chinese Acad Sci Inst Atmospher Phys Beijing Peoples R China NASA Headquarters Div Earth Sci Sci Mission Directorate Washington DC USA ESA Keplerlaan 1 NL-2201 AZ Noordwijk Netherlands Taras Shevchenko Natl Univ Kyiv Kiev Ukraine Kyoto Coll Grad Studies Informat Kyoto Japan Kindai Univ Fac Sci & Engn Osaka Japan Royal Netherlands Meteorol Inst De Bilt Netherlands NASA Langley Res Ctr Hampton VA 23665 USA CNES Direct Innovat Applicat & Sci DIA Toulouse France Chinese Acad Sci Changchun Inst Opt Fine Mech & Phys Changchun Jilin Peoples R China Chinese Acad Sci Shanghai Inst Tech Phys Shanghai Peoples R China

Polarimetry is one of the most promising types of remote sensing for improved characterization of atmospheric aerosol. Indeed, aerosol particles constitute a highly variable atmospheric component characterized by a large number of parameters describing particle sizes, morphologies (including shape and internal structure), absorption and scattering properties, amounts, horizontal and vertical distribution, etc. Reliable monitoring of all these parameters is very challenging, and therefore the aerosol effects on climate and environment are considered to be among the most uncertain factors in climate and environmental research. In this regard, observations that provide both the angular distribution of the scattered atmospheric radiation as well as its polarization state at multiple wavelengths covering the UV-SWIR spectral range carry substantial implicit information on the atmospheric composition. Therefore, high expectations in improving aerosol characterization are associated with detailed passive photopolarimetric observations. The critical need to use space-borne polarimetry for global accurate monitoring of detailed aerosol properties was first articulated in the late 1980s and early 1990s. By now, several orbital instruments have already provided polarization observations from space, and a number of advanced missions are scheduled for launch in the coming years by international and national space agencies. The first and most extensive record of polarimetric imagery was provided by POLDER-I, POLDER-II, and POLDER/PARASOL multi-angle multi-spectral polarization sensors. Polarimetric observations with the POLDER-like design intended for collecting extensive multi-angular multi-spectral measurements will be provided by several instruments, such as the MAI/TG-2, CAPI/TanSat, and DPC/GF-5 sensors recently launched by the Chinese Space Agency. Instruments such as the 3MI/MetOp-SG, MAIA, SpexOne and HARP2 on PACE, POSP, SMAC, PCF, DPC-Lidar, ScanPol and MSIP/Aerosol-UA,

关键词： Aerosols Remote sensing Polarimetry Radiative transfer retrieval algorithms

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Estimate of boundary-layer depth in Nanjing city using aerosol lidar data during 2016-2017 winter

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ATMOSPHERIC ENVIRONMENT 2019年 205卷 67-77页

作者： Fan, Sihui Gao, Zhiqiu Kalogiros, John Li, Yubin Yin, Jian Li, Xin Nanjing Univ Informat Sci & Technol Climate & Weather Disasters Collaborat Innovat Ct Sch Atmospher Phys Key Lab Aerosol Cloud PrecipitatChina Meteorol A Nanjing 210044 Jiangsu Peoples R China Chinese Acad Sci Inst Atmospher Phys State Key Lab Atmospher Boundary Layer Phys & Atm Beijing 100029 Peoples R China Natl Observ Athens Inst Environm Res & Sustainable Dev Athens 11810 Greece

The planetary boundary-layer (PBL) structure was investigated using observations from single aerosol lidar, eddy covariance (EC) system, and automatic meteorological station (AWS) in the north of Nanjing city during an air pollution episode in 2016-2017 winter. Based on seven days' observations under clear to polluted day, we present the temporal variations of the aerosol extinction profiles observed by lidar, and then inter-compare PBL depth retrieved from individual gradient methods. The results show that the gradient method (GM) generated the lowest PBL depth. In contrast to the cubic root gradient method (CRGM), which determined PBL depth ranging from 172 m to 1575 m during the observation period, the logarithm gradient method (LGM) and normalized gradient method (NGM) generated similar results and both tended to overestimate PBL depth on polluted days. The CRGM performed better than LGM and NGM in case of multiple backscatter layers and could detect low level layers, while the GM was biased at low heights probably due to the effect of lidar overlap function. Based on these measurements, the evolution of boundary layer structures and PBL depth over clean days and polluted days were compared. The results show that (1) on clean days, the strong surface turbulence exchange make the PBL depth fully developed and the PBL depth had obvious characteristics of diurnal variation;the maximum depth of PBL was 1560 m for CRGM;and (2) on polluted days, the high pressure system and lower wind was favorable to the accumulation of air pollutants, and thus generating less turbulence by reducing surface radiation. These conditions on polluted days led to smaller PBL depth than those on clean days, and the maximum depth of PBL was 660 m for CRGM. Besides, the diurnal variation of PBL depth on polluted days was weaker than those on clean days.

关键词： Inter-comparison PBL depth Lidar retrieval algorithms Air pollution

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Long-term variation of phytoplankton biomass and physiology in Taihu lake as observed via MODIS satellite

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WATER RESEARCH 2019年 153卷 187-199页

作者： Huang, Changchun Zhang, Yunlin Huang, Tao Yang, Hao Li, Yunmei Zhang, Zhigang He, Mengying Hu, Zhujun Song, Ting Zhu, A-xing Nanjing Normal Univ Jiangsu Ctr Collaborat Innovat Geog Informat Reso Nanjing 210023 Jiangsu Peoples R China Nanjing Normal Univ Minist Educ Key Lab Virtual Geog Environm Nanjing 210023 Jiangsu Peoples R China Nanjing Normal Univ Sch Geog Sci Nanjing 210023 Jiangsu Peoples R China Chinese Acad Sci Nanjing Inst Geog & Limnol State Key Lab Lake Sci & Environm Nanjing 210008 Jiangsu Peoples R China Environm Monitoring Ctr Wuxi 214000 Peoples R China Univ Wisconsin Dept Geog Madison WI 53706 USA

Estimation of phytoplankton biomass (noted as phytoplankton carbon, C-phyto) and evaluation of phytoplankton physiology is central to the estimation of primary productivity and the carbon cycle. This issue has been widely considered in oceans but not in inland water. Here, we develop experiential and semi analytical models, which validated by independent in situ measurement data, respectively, to derive C-phyto and phytoplankton absorption coefficient at 675 nm (a(ph)(675)) from MODIS. The effects of nutrients and temperature on the seasonal variation of phytoplankton physiology were assessed through a novel proxy of C-phyto to a(ph)(675) ratio (C-phyto/a(ph)(675)) over the Lake Taihu, the third largest lake in China. Significant seasonal climatological cycles of C-phyto, a(ph)(675) and C-phyto/a(ph)(675) were observed in Lake Taihu, especially in Meiliang Bay and Zhushan Bay, where algal blooms occur frequently. The highest C-phyto and a(ph)(675) values were observed in summer due to the growth of phytoplankton biomass and chlorophyll-a concentration. Lower values were observed in winter and spring, which are characterized by relatively high total nitrogen levels and low irradiance, owing to the low temperature astricts the algae growth. However, the C-phyto/a(ph)(675) shows an opposite trend compared to C-phyto and a(ph)(675), which have high values in winter and low values in summer. The analysis of C-phyto, a(ph)(675) and C-phyto/aph(675) with total phosphorus (TP) levels and temperature indicates that TP are the main positive driver of the increase in C-phyto and a(ph)(675) and negatively regulate C-phyto/a(ph)(675). Warming promotes an increase in C-phyto and a(ph)(675) and restricts C-phyto/a(ph)(675) in summer. Biomass and nutrient levels are the primary drivers of the decrease of C-phyto/a(ph)(675) in such a typical eutrophic lake. The results present some new findings compared to previous oceanic studies and expand our knowledge in the study of phytoplankt

关键词： Eutrophic lake Phytoplankton absorption coefficient Satellite data retrieval algorithms

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Surface Meteorological Conditions and Boundary Layer Height Variations During an Air Pollution Episode in Nanjing, China

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JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES 2019年第6期124卷 3350-3364页

作者： Yin, J. Gao, C. Y. Hong, J. Gao, Z. Li, Y. Li, X. Fan, S. Zhu, B. Nanjing Univ Informat Sci & Technol Sch Atmospher Phys Climate & Weather Disasters Collaborat Innovat Ct Key Lab Aerosol Cloud PrecipitatChina Meteorol A Nanjing Jiangsu Peoples R China Columbia Univ Dept Earth & Environm Sci New York NY USA Yonsei Univ Dept Atmospher Sci Seoul South Korea Chinese Acad Sci Inst Atmospher Phys State Key Lab Atmospher Boundary Layer Phys & Atm Beijing Peoples R China

The evolution of planetary boundary layer (PBL) was investigated using observations from a laser ceilometer, an eddy covariance system, and an automatic meteorological station in the north of Nanjing city during an air pollution episode in 2016-2017 winter. Based on 7-day observation under clean to polluted day, we recorded the temporal variations of backscatter signals observed by the ceilometer, and then intercompared the planetary boundary layer height (PBLH) retrieved from individual methods. The results show that backscatter signal gradient, standard deviation, and wavelet transform analysis methods generated similar PBLH values and PBL diurnal variation patterns. Moreover, the PBL structure varied diurnally, with distinct patterns corresponding to clean and polluted days. Based on these measurements, the relationships between PBLH, weather conditions, and contaminants were analyzed. Results show that on clean days, strong surface turbulence exchange makes the PBL fully developed and makes the PBLH increase sharply after sunrise, with a maximum of 1,483m;on polluted days, stable synoptic conditions and the weaker wind speeds facilitated the accumulation of air pollutants, leading to smaller net surface radiation and weaker turbulence. Consequently, these conditions during polluted days led to lower PBLH values, which were typically less than 900m.

关键词： planetary boundary layer height ceilometer retrieval algorithms air pollution Nanjing

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Validation of Carbon Trace Gas Profile retrievals from the NOAA-Unique Combined Atmospheric Processing System for the Cross-Track Infrared Sounder

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REMOTE SENSING 2020年第19期12卷 3245-3245页

作者： Nalli, Nicholas R. Tan, Changyi Warner, Juying Divakarla, Murty Gambacorta, Antonia Wilson, Michael Zhu, Tong Wang, Tianyuan Wei, Zigang Pryor, Ken Kalluri, Satya Zhou, Lihang Sweeney, Colm Baier, Bianca C. McKain, Kathryn Wunch, Debra Deutscher, Nicholas M. Hase, Frank Iraci, Laura T. Kivi, Rigel Morino, Isamu Notholt, Justus Ohyama, Hirofumi Pollard, David E. Te, Yao Velazco, Voltaire A. Warneke, Thorsten Sussmann, Ralf Rettinger, Markus IMSG Inc NESDIS Ctr Satellite Applicat & Res STAR NOAA College Pk MD 20740 USA UMD Dept Atmospher & Ocean Sci College Pk MD 20740 USA NASA Goddard Space Flight Ctr Climate & Radiat Lab Greenbelt MD 20771 USA NOAA NESDIS STAR College Pk MD 20740 USA NOAA JPSS Program Off Lanham MD 20706 USA NOAA Global Monitoring Lab GML Boulder CO 80305 USA Univ Colorado Cooperat Inst Res Environm Sci Boulder CO 80305 USA Univ Toronto Dept Phys Toronto ON M5S 1A7 Canada Univ Wollongong Ctr Atmospher Chem Sch Earth Atmospher & Life Sci Wollongong NSW 2522 Australia Karlsruhe Inst Technol Inst Meteorol & Climate Res IMK ASF D-76137 Karlsruhe Germany NASA Ames Res Ctr Atmospher Sci Branch Mail Stop 245-5 Moffett Field CA 94035 USA Finnish Meteorol Inst Space & Earth Observat Ctr Tahtelantie 62 Sodankyla 99600 Finland Natl Inst Environm Studies NIES Satellite Remote Sensing Sect Onogawa 16-2 Tsukuba Ibaraki 3058506 Japan Natl Inst Environm Studies NIES Satellite Observat Ctr Onogawa 16-2 Tsukuba Ibaraki 3058506 Japan Univ Bremen Inst Environm Phys D-28195 Bremen Germany Natl Inst Water & Atmospher Res Ltd Hamilton 3216 New Zealand PSL Univ Lab Etud Rayonnement & Mat Astrophys & Atmosphere Observ Paris Sorbonne UnivCNRS F-75005 Paris France Karlsruhe Inst Technol IMK IFU D-82467 Garmisch Partenkirchen Germany

This paper provides an overview of the validation of National Oceanic and Atmospheric Administration (NOAA) operational retrievals of atmospheric carbon trace gas profiles, specifically carbon monoxide (CO), methane (CH4) and carbon dioxide (CO2), from the NOAA-Unique Combined Atmospheric Processing System (NUCAPS), a NOAA enterprise algorithm that retrieves atmospheric profile environmental data records (EDRs) under global non-precipitating (clear to partly cloudy) conditions. Vertical information about atmospheric trace gases is obtained from the Cross-track Infrared Sounder (CrIS), an infrared Fourier transform spectrometer that measures high resolution Earth radiance spectra from NOAA operational low earth orbit (LEO) satellites, including the Suomi National Polar-orbiting Partnership (SNPP) and follow-on Joint Polar Satellite System (JPSS) series beginning with NOAA-20. The NUCAPS CO, CH4, and CO2 profile EDRs are rigorously validated in this paper using well-established independent truth datasets, namely total column data from ground-based Total Carbon Column Observing Network (TCCON) sites, and in situ vertical profile data obtained from aircraft and balloon platforms via the NASA Atmospheric Tomography (ATom) mission and NOAA AirCore sampler, respectively. Statistical analyses using these datasets demonstrate that the NUCAPS carbon gas profile EDRs generally meet JPSS Level 1 global performance requirements, with the absolute accuracy and precision of CO 5% and 15%, respectively, in layers where CrIS has vertical sensitivity;CH4 and CO2 product accuracies are both found to be within +/- 1%, with precisions of approximate to 1.5% and <0.5%, respectively, throughout the tropospheric column.

关键词： satellite cal val error analysis greenhouse gases carbon monoxide methane carbon dioxide trace gas remote sensing retrieval algorithms satellite applications

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Hyperspectral radiative transfer modeling to explore the combined retrieval of biophysical parameters and canopy fluorescence from FLEX - Sentinel-3 tandem mission multi-sensor data

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REMOTE SENSING OF ENVIRONMENT 2018年 204卷 942-963页

作者： Verhoef, Wouter van der Tol, Christiaan Middleton, Elizabeth M. Univ Twente Fac Geoinformat Sci & Earth Observat ITC Hengelosestr 99POB 217 NL-7500 AE Enschede Netherlands NASA Goddard Space Flight Ctr Biospher Sci Lab Greenbelt MD 20771 USA

The FLuorescence EXpiorer (FLEX) satellite mission, selected as ESA's 8th Earth Explorer, has been designed for the measurement of sun-induced fluorescence (F) spectra emitted by plants. This will be accomplished through a multi-sensor approach by placing it in a common orbit in tandem with the Sentinel-3 (S3) mission, which will have two optical sensors on board, OLCI (Ocean and Land Colour Instrument) and SLSTR (Sea and Land Surface Temperature Radiometer) to complement FLEX. These S3 instruments will be used in combination with the imaging spectrometers on board FLEX to provide data useful for atmospheric correction of FLEX data. However, a fully synergetic approach, i.e. by exploiting the spectral and directional information from all tandem mission instruments together, is an attractive alternative which is explored in this paper. By employing all combined top of-atmosphere (TOA) spectral radiance data, one can (i) characterize the relevant optical properties of the atmosphere, (ii) retrieve biophysical canopy properties including the associated reflectance anisotropy, and (iii) retrieve a more accurate and consistent canopy F. Regarding retrieval methods, Fraunhofer Line Depth (FLD) and Spectral Fitting (SF) are well-known techniques applied to hyperspectral data. Both methods depend on a high spectral resolution and assume a Lambertian (isotropic) canopy reflectance. However, most vegetation canopies are non-Lambertian. This implies that, in particular when ignoring the anisotropic surface reflection, substantial retrieval errors can occur due to the interaction between atmospheric absorption bands and surface reflectance anisotropy. In this paper, a novel method based on spectral radiative transfer (RT) modeling is proposed, in which coupled RT models are used to simulate TOA radiance spectra. These are then matched with `measured' spectra in order to retrieve surface fluorescence, along with a suite of biophysical parameters, by model inversion through optim

关键词： Sun-induced fluorescence FLEX mission Sentinel-3 retrieval algorithms Biophysical parameters Radiative transfer Simulation SCOPE SAIL Anisotropy

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Maximum-Likelihood retrieval of Volcanic Ash Concentration and Particle Size From Ground-Based Scanning Lidar

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IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 2018年第10期56卷 5824-5842页

作者： Mereu, Luigi Scollo, Simona Mori, Saverio Boselli, Antonella Leto, Giuseppe Marzano, Frank S. Sapienza Univ Rome Dipartimento Ingn Informaz I-00184 Rome Italy Univ Aquila CETEMPS Ctr Excellence I-67100 Laquila Italy Ist Nazl Geofis & Vulcanol Osservatorio Etneo Sez Catania I-95125 Catania Italy CNR Ist Metodol Anal Ambientale I-85055 Potenza Italy Ist Nazl Astrofis Osservatorio Astrofis Catania I-95123 Catania Italy

An inversion methodology, named maximum-likelihood (ML) volcanic ash light detection and ranging (Lidar) retrieval (VALR-ML), has been developed and applied to estimate volcanic ash particle size and ash mass concentration within volcanic plumes. Both estimations are based on the ML approach, trained by a polarimetric backscattering forward model coupled with a Monte Carlo ash microphysical model. The VALR-ML approach is applied to Lidar backscattering and depolarization profiles, measured at visible wavelength during two eruptions of Mt. Etna, Catania, Italy, in 2010 and 2011. The results are compared with those of ash products derived from other parametric retrieval algorithms. A detailed comparison among these different retrieval techniques highlights the potential of VALR-ML to determine, on the basis of a physically consistent approach, the ash cloud area that must be interdicted to flight operations. Moreover, the results confirm the usefulness of operating scanning Lidars near active volcanic vents.

关键词： Ash mean size backscattering and depolarization explosive eruption retrieval algorithms scanning light detection and ranging (Lidar) volcanic ash concentration

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THE BIOMASS MISSION retrieval algorithms: RESULTS FROM RECENT CAMPAIGNS

THE BIOMASS MISSION RETRIEVAL ALGORITHMS: RESULTS FROM RECEN...

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IEEE International Geoscience and Remote Sensing Symposium (IGARSS)

作者： Thuy Le Toan Ulander, Lars Papathanassiou, Kostas Rocca, Fabio Quegan, Shaun Davidson, Malcolm Scipal, Klaus Univ Toulouse 3 IRD CESBIO CNRSCNES F-31062 Toulouse France

ISBN: (纸本)9781467311595

The BIOMASS mission is designed to map the full range of the world's above-ground forest biomass, for the needs of national scale inventory and global carbon flux calculations. This objective is achieved with advanced P-band SAR techniques. The P-band biomass measurement concept was based on previous work over the past two decades. During the preparatory phase, new campaigns have been conducted to address critical issues on the biomass retrieval algorithms, over tropical and boreal forests. The collected datasets comprise accurate and complete sets of in situ data and advanced P-band SAR data. This paper presents the retrieval algorithms developed using the collected datasets.

关键词： BIOMASS mission P-band SAR polarimetry Pol-InSAR tomography retrieval algorithms

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