Fraunhofer Lidar Prototype in the Green Spectral Region for Atmospheric Boundary Layer Observations
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Toward Non-Invasive Measurement of Atmospheric Temperature Using Vibro-Rotational Raman Spectra of Diatomic Gases
remote sensing Article Toward Non-Invasive Measurement of Atmospheric Temperature Using Vibro-Rotational Raman Spectra of Diatomic Gases Tyler Capek 1,*,† , Jacek Borysow 1,† , Claudio Mazzoleni 1,† and Massimo Moraldi 2,† 1 Department of Physics, Michigan Technological University, Houghton, MI 49931, USA; [email protected] (J.B.); [email protected] (C.M.) 2 Dipartimento di Fisica e Astronomia, Universita’ degli Studi di Firenze, via Sansone 1, I-50019 Sesto Fiorentino, Italy; massimo.moraldi@fi.infn.it * Correspondence: [email protected] † These authors contributed equally to this work. Received: 8 October 2020; Accepted: 15 December 2020; Published: 17 December 2020 Abstract: We demonstrate precise determination of atmospheric temperature using vibro-rotational Raman (VRR) spectra of molecular nitrogen and oxygen in the range of 292–293 K. We used a continuous wave fiber laser operating at 10 W near 532 nm as an excitation source in conjunction with a multi-pass cell. First, we show that the approximation that nitrogen and oxygen molecules behave like rigid rotors leads to erroneous derivations of temperature values from VRR spectra. Then, we account for molecular non-rigidity and compare four different methods for the determination of air temperature. Each method requires no temperature calibration. The first method involves fitting the intensity of individual lines within the same branch to their respective transition energies. We also infer temperature by taking ratios of two isolated VRR lines; first from two lines of the same branch, and then one line from the S-branch and one from the O-branch. Finally, we take ratios of groups of lines. -
CHAPTER CONTENTS Page CHAPTER 5
CHAPTER CONTENTS Page CHAPTER 5. SPECIAL PROFILING TECHNIQUES FOR THE BOUNDARY LAYER AND THE TROPOSPHERE .............................................................. 640 5.1 General ................................................................... 640 5.2 Surface-based remote-sensing techniques ..................................... 640 5.2.1 Acoustic sounders (sodars) ........................................... 640 5.2.2 Wind profiler radars ................................................. 641 5.2.3 Radio acoustic sounding systems ...................................... 643 5.2.4 Microwave radiometers .............................................. 644 5.2.5 Laser radars (lidars) .................................................. 645 5.2.6 Global Navigation Satellite System ..................................... 646 5.2.6.1 Description of the Global Navigation Satellite System ............. 647 5.2.6.2 Tropospheric Global Navigation Satellite System signal ........... 648 5.2.6.3 Integrated water vapour. 648 5.2.6.4 Measurement uncertainties. 649 5.3 In situ measurements ....................................................... 649 5.3.1 Balloon tracking ..................................................... 649 5.3.2 Boundary layer radiosondes .......................................... 649 5.3.3 Instrumented towers and masts ....................................... 650 5.3.4 Instrumented tethered balloons ....................................... 651 ANNEX. GROUND-BASED REMOTE-SENSING OF WIND BY HETERODYNE PULSED DOPPLER LIDAR ................................................................ -
Stability of Narrow-Band Filter Radiometers in the Solar-Reflective Range
Stability of Narrow-Band Filter Radiometers in the Solar-Reflective Range D. E. Flittner and P. N. Slater Optical Sciences Center, University of Arizona, Tucson, AZ 85721 ABSTRACT:We show that the calibration, with respect to a continuous-spech.umsource, and the stability of radiometers using filters of about 10 nm full width, half maximum (FWHM) in the wavelength interval 0.4 to 1.0 pm, can change by several percent if the filters change in position by only a few nanometres. The cause is the shifts of the passbands of the filters into or out of Fraunhofer lines in the solar spectrum or water vapor or oxygen absorption bands in the Earth's atmosphere. These shifts can be due to ageing accompanied by the absorption of water vapor into the filter or temperature changes for field radiometers, or to outgassing and possibly high energy solar irradiation for space instru- ments such as the MODerate resolution Imaging Spectrometer - Nadir (MODIS-N) proposed for the Earth Observing System. INTRODUCTION sun, but can lead to errors in moderate to high spectral reso- lution measurements of the Earth-atmosphere system if their T IS WELL KNOWN that satellite multispectral sensor data in Ithe visible and near infrared are acquired with spectral band- effect is not taken into account. The concern is that the narrow- widths from about 40 nm (System Probatoire &Observation de band filters in a radiometer may shift, causing them to move la Terre (SPOT) band 2) and 70 nm (Thematic Mapper (TM)band into or out of a region containing a Fraunhofer line, thereby 3) to about 200 and 400 nm (Multispectral Scanner System (MSS) causing a noticeable change in the radiometer output. -
The Solar Spectrum: an Atmospheric Remote Sensing Perspecnve
The Solar Spectrum: an Atmospheric Remote Sensing Perspec7ve Geoffrey Toon Jet Propulsion Laboratory, California Ins7tute of Technology Noble Seminar, University of Toronto, Oct 21, 2013 Copyright 2013 California Instute of Technology. Government sponsorship acknowledged. BacKground Astronomers hate the Earth’s atmosphere – it impedes their view of the stars and planets. Forces them to make correc7ons for its opacity. Atmospheric scien7sts hate the sun – the complexity of its spectrum: • Fraunhofer absorp7on lines • Doppler shis • Spaal Non-uniformi7es (sunspots, limb darKening) • Temporal variaons (transits, solar cycle, rotaon, 5-minute oscillaon) all of which complicate remote sensing of the Earth using sunlight. In order to more accurately quan5fy the composi5on of the Earth’s atmosphere, it is necessary to beFer understand the solar spectrum. Mo7vaon Solar radiaon is commonly used for remote sensing of the Earth: • the atmosphere • the surface Both direct and reflected sunlight are used: • Direct: MkIV, ATMOS, ACE, SAGE, POAM, NDACC, TCCON, etc. • Reflected: OCO, GOSAT, SCIAMACHY, TOMS, etc. Sunlight provides a bright, stable, and spectrally con7nuous source. As accuracy requirements on atmospheric composi5on measurements grows more stringent (e.g. TCCON), beFer representa5ons of the solar spectrum are needed. Historical Context Un7l 1500 (Copernicus), it was assumed that the Sun orbited the Earth. Un7l 1850 sun was assumed 6000 years old, based on the Old Testament. Sunspots were considered openings in the luminous exterior of the sun, through which the sun’s solid interior could be seen. 1814: Fraunhofer discovers absorp7on lines in visible solar spectrum 1854: von Helmholtz calculated sun must be ~20MY old based on heang by gravitaonal contrac7on. -
Spectroscopy and the Stars
SPECTROSCOPY AND THE STARS K H h g G d F b E D C B 400 nm 500 nm 600 nm 700 nm by DR. STEPHEN THOMPSON MR. JOE STALEY The contents of this module were developed under grant award # P116B-001338 from the Fund for the Improve- ment of Postsecondary Education (FIPSE), United States Department of Education. However, those contents do not necessarily represent the policy of FIPSE and the Department of Education, and you should not assume endorsement by the Federal government. SPECTROSCOPY AND THE STARS CONTENTS 2 Electromagnetic Ruler: The ER Ruler 3 The Rydberg Equation 4 Absorption Spectrum 5 Fraunhofer Lines In The Solar Spectrum 6 Dwarf Star Spectra 7 Stellar Spectra 8 Wien’s Displacement Law 8 Cosmic Background Radiation 9 Doppler Effect 10 Spectral Line profi les 11 Red Shifts 12 Red Shift 13 Hertzsprung-Russell Diagram 14 Parallax 15 Ladder of Distances 1 SPECTROSCOPY AND THE STARS ELECTROMAGNETIC RADIATION RULER: THE ER RULER Energy Level Transition Energy Wavelength RF = Radio frequency radiation µW = Microwave radiation nm Joules IR = Infrared radiation 10-27 VIS = Visible light radiation 2 8 UV = Ultraviolet radiation 4 6 6 RF 4 X = X-ray radiation Nuclear and electron spin 26 10- 2 γ = gamma ray radiation 1010 25 10- 109 10-24 108 µW 10-23 Molecular rotations 107 10-22 106 10-21 105 Molecular vibrations IR 10-20 104 SPACE INFRARED TELESCOPE FACILITY 10-19 103 VIS HUBBLE SPACE Valence electrons 10-18 TELESCOPE 102 Middle-shell electrons 10-17 UV 10 10-16 CHANDRA X-RAY 1 OBSERVATORY Inner-shell electrons 10-15 X 10-1 10-14 10-2 10-13 10-3 Nuclear 10-12 γ 10-4 COMPTON GAMMA RAY OBSERVATORY 10-11 10-5 6 4 10-10 2 2 -6 4 10 6 8 2 SPECTROSCOPY AND THE STARS THE RYDBERG EQUATION The wavelengths of one electron atomic emission spectra can be calculated from the Use the Rydberg equation to fi nd the wavelength ot Rydberg equation: the transition from n = 4 to n = 3 for singly ionized helium. -
Observations of Atmospheric Aerosol and Cloud Using a Polarized Micropulse Lidar in Xi’An, China
atmosphere Article Observations of Atmospheric Aerosol and Cloud Using a Polarized Micropulse Lidar in Xi’an, China Chao Chen 1,2,3,4, Xiaoquan Song 1,* , Zhangjun Wang 1,2,3,4,*, Wenyan Wang 5, Xiufen Wang 2,3,4, Quanfeng Zhuang 2,3,4, Xiaoyan Liu 1,2,3,4 , Hui Li 2,3,4, Kuntai Ma 1, Xianxin Li 2,3,4, Xin Pan 2,3,4, Feng Zhang 2,3,4, Boyang Xue 2,3,4 and Yang Yu 2,3,4 1 College of Information Science and Engineering, Ocean University of China, Qingdao 266100, China; [email protected] (C.C.); [email protected] (X.L.); [email protected] (K.M.) 2 Institute of Oceanographic Instrumentation, Qilu University of Technology (Shandong Academy of Sciences), Qingdao 266100, China; [email protected] (X.W.); [email protected] (Q.Z.); [email protected] (H.L.); [email protected] (X.L.); [email protected] (X.P.); [email protected] (F.Z.); [email protected] (B.X.); [email protected] (Y.Y.) 3 Shandong Provincial Key Laboratory of Marine Monitoring Instrument Equipment Technology, Qingdao 266100, China 4 National Engineering and Technological Research Center of Marine Monitoring Equipment, Qingdao 266100, China 5 Xi’an Meteorological Bureau of Shanxi Province, Xi’an 710016, China; [email protected] * Correspondence: [email protected] (X.S.); [email protected] (Z.W.) Abstract: A polarized micropulse lidar (P-MPL) employing a pulsed laser at 532 nm was developed by the Institute of Oceanographic Instrumentation, Qilu University of Technology (Shandong Academy Citation: Chen, C.; Song, X.; Wang, of Sciences). -
The Demographics of Massive Black Holes
The fifth element: astronomical evidence for black holes, dark matter, and dark energy A brief history of astrophysics • Greek philosophy contained five “classical” elements: °earth terrestrial; subject to °air change °fire °water °ether heavenly; unchangeable • in Greek astronomy, the universe was geocentric and contained eight spheres, seven holding the known planets and the eighth the stars A brief history of astrophysics • Nicolaus Copernicus (1473 – 1543) • argued that the Sun, not the Earth, was the center of the solar system • the Copernican Principle: We are not located at a special place in the Universe, or at a special time in the history of the Universe Greeks Copernicus A brief history of astrophysics • Isaac Newton (1642-1747) • the law of gravity that makes apples fall to Earth also governs the motions of the Moon and planets (the law of universal gravitation) ° thus the square of the speed of a planet in its orbit varies inversely with its radius ⇒ the laws of physics that can be investigated in the lab also govern the behavior of stars and planets (relative to Earth) A brief history of astrophysics • Joseph von Fraunhofer (1787-1826) • discovered narrow dark features in the spectrum of the Sun • realized these arise in the Sun, not the Earth’s atmosphere • saw some of the same lines in the spectrum of a flame in his lab • each chemical element is associated with a set of spectral lines, and the dark lines in the solar spectrum were caused by absorption by those elements in the upper layers of the sun ⇒ the Sun is made of the same elements as the Earth A brief history of astrophysics ⇒ the Sun is made of the same elements as the Earth • in 1868 Fraunhofer lines not associated with any known element were found: “a very decided bright line...but hitherto not identified with any terrestrial flame. -
Fraunhofer Lines and the Composition of the Sun 1 Summary 2 Papers and Datasets 3 Scientific Background
Fraunhofer lines and the composition of the Sun 1 Summary The purpose of this lab is for you to examine the spectrum of the Sun, to learn about the composition of the Sun (it’s not just hydrogen and helium!), and to understand some basic concepts of spectroscopy. 2 Papers and datasets These documents are all available on the course web page. • Low resolution spectrum of the Sun (from the National Solar Observatory) • Absorption lines of various elements (from laserstars.org and NASA’s Goddard Space Flight Center) • Table of abundances in the Sun 3 Scientific background 3.1 Spectroscopy At its most basic level, spectroscopy is simply splitting light up into different wavelengths. The classic example is a prism: white light goes in, and a rainbow comes out. Spectroscopy for physics and astronomy usually drops the output onto some kind of detector that records the flux at different wavelengths as a “stripe” across the detector. In other words, the output is a data table that lists the measured flux as a function of pixel number. An critical aspect of spectroscopy is wavelength calibration: what wavelength corresponds to which pixel number? Note that that relationship does not have to be — and is often not — linear. That is, the mapping of wavelength to pixel is not a linear relationship, but something more complicated. 3.2 The Sun The Sun is mostly hydrogen and after that mostly helium. You have learned about the fusion processes in the Sun and in other stars that gradually convert hydrogen to helium and then, for some stars, onward to carbon, nitrogen, and oxygen (CNO cycle), and further upward through the periodic table to iron. -
Sea Surface Wind Speed Estimation from Space-Based Lidar Measurements Y
Sea surface wind speed estimation from space-based lidar measurements Y. Hu, K. Stamnes, M. Vaughan, Jacques Pelon, C. Weimer, D. Wu, M. Cisewski, W. Sun, P. Yang, B. Lin, et al. To cite this version: Y. Hu, K. Stamnes, M. Vaughan, Jacques Pelon, C. Weimer, et al.. Sea surface wind speed estimation from space-based lidar measurements. Atmospheric Chemistry and Physics, European Geosciences Union, 2008, 8, pp.3593-3601. hal-00328304v2 HAL Id: hal-00328304 https://hal.archives-ouvertes.fr/hal-00328304v2 Submitted on 20 May 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Atmos. Chem. Phys., 8, 3593–3601, 2008 www.atmos-chem-phys.net/8/3593/2008/ Atmospheric © Author(s) 2008. This work is distributed under Chemistry the Creative Commons Attribution 3.0 License. and Physics Sea surface wind speed estimation from space-based lidar measurements Y. Hu1, K. Stamnes2, M. Vaughan1, J. Pelon3, C. Weimer4, D. Wu5, M. Cisewski1, W. Sun1, P. Yang6, B. Lin1, A. Omar1, D. Flittner1, C. Hostetler1, C. Trepte1, D. Winker1, G. Gibson1, and M. Santa-Maria1 1Climate Science Branch, NASA Langley Research Center, Hampton, VA, USA 2Dept. -
Processing Jump Point of Lidar Detection Data and Inversing the Aerosol Extinction Coefficient
The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XLII-3/W9, 2019 ISPRS Workshop on Remote Sensing and Synergic Analysis on Atmospheric Environment (RSAE), 25–27 October 2019, Nanjing, China PROCESSING JUMP POINT OF LIDAR DETECTION DATA AND INVERSING THE AEROSOL EXTINCTION COEFFICIENT Hailun Zhang1, Hu Zhao1,﹡, Yapeng Liu2, Xingkai Wang2, Chang Shu2 1School of Electrical and Information Engineering, North MinZu University Yinchuan 750021, China - [email protected], [email protected] 2School of computer science and engineering, North MinZu University Yinchuan 750021, China - [email protected], [email protected], [email protected] Commission Ⅲ, WG Ⅲ/8 KEY WORDS:Extinction Coefficient, Jump Point, Fitting, Interpolation, Invention Method ABSTRACT: For a long time, the research of the optical properties of atmospheric aerosols has aroused a wide concern in the field of atmospheric and environmental. Many scholars commonly use the Klett method to invert the lidar return signal of Mie scattering. However, there are always some negative values in the detection data of lidar, which have no actual meaning,and which are jump points. The jump points are also called wild value points and abnormal points. The jump points are refered to the detecting points that are significantly different from the surrounding detection points, and which are not consistent with the actual situation. As a result, when the far end point is selected as the boundary value, the inversion error is too large to successfully invert the extinction coefficient profile. These negative points are jump points, which must be removed in the inversion process. In order to solve the problem, a method of processing jump points of detection data of lidar and the inversion method of aerosol extinction coefficient is proposed in this paper. -
Development of Lidar Techniques to Estimate
DEVELOPMENT OF LIDAR TECHNIQUES TO ESTIMATE ATMOSPHERIC OPTICAL PROPERTIES by Mariana Adam A dissertation submitted to the Johns Hopkins University in conformity with the requirements for the degree of Doctor of Philosophy Baltimore, Maryland October, 2005 © Mariana Adam 2005 All rights reserved DEVELOPMENT OF LIDAR TECHNIQUES TO ESTIMATE ATMOSPHERIC OPTICAL PROPERTIES by Mariana Adam ABSTRACT The modified methodologies for one-directional and multiangle measurements, which were used to invert the data of the JHU elastic lidar obtained in clear and polluted atmospheres, are presented. The vertical profiles of the backscatter lidar signals at the wavelength 1064 nm were recorded in Baltimore during PM Supersite experiment. The profiles of the aerosol extinction coefficient over a broad range of atmospheric turbidity, which includes a strong haze event which occurred due to the smoke transport from Canadian forest fires in 2002, were obtained with the near-end solution, in which the boundary condition was determined at the beginning of the complete overlap zone. This was done using an extrapolation from the ground level of the aerosol extinction coefficient, calculated with the Mie theory. For such calculations the data of the ground-based in-situ instrumentation, the nephelometer and two particle size analyzers were used. An analysis of relative errors in the retrieved extinction profiles ii due to the uncertainties in the established boundary conditions was performed using two methods to determine the ground-level extinction coefficient, which in turn, imply two methods to determine aerosol index of refraction (using the nephelometer data and chemical species measurements). The comparison of the three analytical methods used to solve lidar equation (near-end, far-end and optical-depth solutions) is presented. -
194 7Mnras.107. .274M the Fraunhofer Lines of The
THE FRAUNHOFER LINES OF THE SOLAR SPECTRUM .274M {George Darwin Lecture, delivered by Professor M. G. J. Minnaert, on 1947 May 9) A lecture on Fraunhofer lines has inevitably a somewhat abstruse character.. 7MNRAS.107. The spectroscopist could not show you any of the wonderful pictures which the 194 telescope reveals. A spectrum looks at first sight like a rather dull succession of bright and dark stripes. But now comes the observer, using his refined methods and discovering the infinite variety of shades and halftones in that spectrum, the full richness of that chiaroscuro. And then comes the theorist, deriving by the power of his phantasy how that music of undulating spectral lines is due to the airy dance of the atoms in the fiery radiation of the Sun. Actually, the investigation of Fraunhofer lines is so fascinating, so rich in observational details and so important theoretically, that I shall have to restrict myself to one part of the subject: photometry; even then, I shall only be able to present before you some of the more important moments in the development of our knowledge and a general view of the present state of the problems involved. In this frame I shall give an account more particularly of the work done at Utrecht because with this work are connected so many personal reminiscences ; but we all know that progress in this field is due to the cooperation of many scientists all over the world.* Already the first observations of a good solar spectrum revealed, that among the individual Fraunhofer lines there is a great variety of intensity profiles.