bluuebunny/crossref_metadata_2025 huggingface dataset:
Rayleigh Lidar Measurements at Toronto
Authors: Whiteway J.A. , Carswell A.I.
Published: February 2023

Since June 1991, Rayleigh lidar measurements at York University are being carried out on a continuous basis (every clear night). The goal is to understand the properties of gravity waves and their effects on thermal structure in the mesosphere and upper stratosphere. This involves detailed study of: propagation of individual waves, interactions amongst gravity waves, gravity wave spectra, general wave characteristics as a function of altitude, the relationship between gravity waves and disturbances in thermal structure, and a developing climatology.
Performance Calculations and Test of SCIAMACHY Detector Modules
Authors: Goede A.P.H. , Hoogeveen R.W.M. , van der A R.J. , de Vries J.
Published: February 2023

SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CartograpHY) has been selected by ESA to fly on the first ENVISAT mission (1998). The Instrument Requirements originate from the Max Planck Institut für Chemie in Mainz under principal investigator J.P. Burrows /1/. The instrument comprises an imaging spectrometer operating in the wavelength range of 240-2385 nm, at a resolution of ~0.2 nm. Measurements will be performed in the nadir mode, in the limb mode and in the sun/moon occultation mode.
Atmospheric Remote Sensing Studies at the National Institute for Environmental Studies (NIES), Japan
Authors: Sasano Yasuhiro , Nakane Hideaki , Sugimoto Nobuo
Published: February 2023

In the middle of 1970's, we began lidar studies at NIES with constructing a mobile Mie lidar for application to lower atmospheric structure studies in relation to air pollution phenomena. A large-scale lidar was built in 1979 for the purpose of developing measurement techniques for aerosol distribution over a wide-area. The large lidar was also used for studies on atmospheric structures such as mixed layer and sea-breeze front.
Progress in Development of a Tm:YAG Coherent Lidar for High Spatial and Velocity Resolution Wind Measurement
Authors: Grund Christian J. , Post Madison J. , Chan Kin Pui
Published: February 2023

The changing thermodynamic and chemical properties of the atmosphere are largely controlled by the exchange of heat, moisture, and momentum within the land and ocean boundary layers. Understanding anthropogenic impacts on air quality and the climate requires knowledge of the sources, sinks, and turbulent exchange processes for pollutants and greenhouse gases. Present knowledge of these processes largely depends on flux measurements acquired using in situ sensors on aircraft, towers, and tethered balloons, or by radar, sodar, and lidar remote sensors. Large eddy simulation models (Moeng and Wyngaard, 1988) have added significantly to current understanding of these turbulent exchange processes, but significant improvements in the spatial, temporal, and velocity resolution of current measurement capabilities for wind and concentration fluctuations are needed to provide adequate data sets from which improved theories and models of turbulent transfer can be developed and verified. Remote measurement instruments with sufficient resolution would enable flux measurements by eddy correlation techniques, satisfying these needs.
Molecular Absorption Parameter Measurements for Remote Sensing Applications
Authors: Chu Zhiping , Chen Li , Cheo Peter K.
Published: February 2023

Mid-infrared region of the spectrum is rich with vibrational-rotational lines of molecular pollutants within the atmosphere. Differential absorption lidar (DIAL) technique has commonly been used to remotely detect the low concentrations of the pollutants.1-3 This technique depends critically on the assumed molecular absorption line frequency, line strength, linewidth, pressure shift of line frequency and temperature dependence of line width. In the present study, a novel and compact IR tunable laser system with narrow linewidth and wide tunability 4 in the spectral range from 9.1 to 12.5 μm has been built. Our objective is to measure the line parameters of the atmospheric gases by taking advantage of the high power and wide tunability of this sideband laser. Those parameters are important for remote sensing applications between 9.1-12.5 μm. This paper presents the measurements of absorption line frequencies, frequency shifts due to pressure, line strengths and self-broadened Lorentz linewidths of NH3 and C2H4 transitions which were covered by the CO2 laser used in the experiment.
Forward model comparisons with the High-resolution Interferometer Sounder (HIS)
Authors: Knuteson R.O. , Revercomb H.E. , Smith W.L.
Published: February 2023

A subject of continuing interest is the accuracy of current line-by-line transmittance models in the description of atmospheric radiative transfer. The most direct way to investigate this question is to compare accurate measurements of atmospheric radiation with calculations based upon good in-situ measurements of atmospheric state parameters. This summary brings up to date the results of earlier comparisons of observations with calculations to illustrate the outstanding issues remaining. The earlier results were summarized in the 1990 Incline Village meeting of the Optical Society.[Revercomb 1990]
Relationships Between Lidar Backscatter and Meteorological Fields
Authors: McCaul Eugene W. , Bowdle David A. , Cutten Dean R. , Menzies Robert T. , Spinhirne James D.
Published: February 2023

A primary concern in the design of satellite-borne Doppler lidar wind sensors is the extent to which atmospheric aerosol concentrations are sufficient to produce backscatter intense enough for accurate retrieval of wind estimates. Although some climatological data regarding the large-scale spatial and seasonal evolution of the global tropospheric aerosol field have become available within the past decade (Kent et al., 1991), our knowledge of the structure of aerosol fields on the synoptic scale and mesoscale remains inadequate. In an effort to investigate the structure of these fields and their relationships to meteorological phenomena, lidars operating at several wavelengths were flown aboard the National Aeronautics and Space Administration's (NASA) DC8 on a number of flights in the Pacific Ocean basin during late 1989 and early 1990 as part of the Global Backscatter Experiment (GLOBE; Bowdle et al., 1991).
HNO3 Profiles Obtained During EASOE
Authors: Murcray F.J. , Starkey J.R. , Williams W.J. , Matthews W.A. , Schmidt U. , Aimedieu P. , Camy-Peyret C.
Published: February 2023

The detection of the Antarctic ozone hole by Farman et all has led to increased interest in obtaining data at high latitudes on the altitude distribution of many of the constituents involved in the photochemistry of the ozone layer. Data concerning the altitude profile of constituents at stratospheric altitudes is generally obtained using instruments flown on large balloons. Launch and recovery of the instrumentation flown on such balloons at remote sites is difficult. In order to reduce these difficulties we have developed small grating spectrometer system which can be flown on small balloons. HNO3is of particular interest in high latitude photochemistry since it is involved in the heterogeneous reactions occurring during the winter. The spectrometer was designed specifically to obtain data on HNO3however the spectral region scanned (8μ to 13μ) includes features due to CH4, N2O, O3, F12 and F11. The system is used to measure the atmospheric spectral emission and its change with altitude as the balloon ascends. The change in spectral radiance with altitude is used to obtain profile data on the constituents of interest.
On Determining the Carbon Budget (CO2 and CO) of the Lower Thermosphere from Non-Equilibrium Infrared Radiance
Authors: Winick Jeremy R. , Picard Richard H. , Wintersteiner Peter P. , Paboojian A.J. , Joseph R.A.
Published: February 2023

The high resolution (1 cm-1) limb emission spectra taken with the CIRRIS 1A interferometer on STS-39 over tangent heights from 50 to 200 km provides an opportunity to test the detailed non-LTE models of the emission and investigate methods for determining the carbon budget of the lower thermosphere from coincident measurement of the 4.3 μm CO2 v3 band and the 4.7 μm CO band. Earlier theory (Kumer and James, 1977, López-Puertas et. al., 1986, López-Puertas and Taylor, 1989) did not have high resolution spectral data to thoroughly validate their theories. López-Puertas and Taylor (1989) compared their models to SAMS data, a situation that needed an additional line-by-line model to filter their model results in a manner similar to the pressure modulated radiometer measurement. The high resolution spectra provide a much more stringent test of the theoretical non-LTE infrared emission models. We limit our discussion to the daytime spectra for a number of reasons. (1) The solar excitation leads to a large increase in signal, increasing the altitude to which good spectra can be obtained, (2) the domination of solar excitation simplifies the determination of the CO and CO2 densities since other non-local earthshine processes become less important, and (3), the solar excitation of the CO2v3 states yields a rich spectrum including isotopic and hot-band emission.
Retrieval of Atmospheric State Parameters from High Resolution Spectral Radiance Data
Authors: Clough Shepard A.
Published: February 2023

The retrieval of temperature and molecular trace gas profiles from spectral radiance data is an important but complex problem in optimization. In this presentation we are concerned with profile retrievals along the radiating path, examples of which include zenith remote sensing from the surface and nadir remote sensing from space. The latter application is of particular interest in the context of obtaining global maps of trace molecular species using high resolution spectral radiance data from spectrometers orbiting in space. The retrieval method to be explored is the method of non-linear least squares in which the state parameters are optimized to obtain the minimum variance of the spectral residuals, Rodgers (1976) and Clough et al. (1990,1991). The residuals are defined as the spectral differences between the measurement and the calculated result from an appropriate forward radiative transfer model. In the present case we are concerned with high resolution so that the objective of the retrieval process is to obtain for a given spatial resolution, the most probable profile values for the state parameter of interest.
Simultaneous Inference of Multiple Atmospheric Parameters using Multiple Channels of Information
Authors: Marshall Benjamin T. , Gordley Larry L.
Published: February 2023

The increasing complexity of the new generation of limb viewing atmospheric remote sensing instruments have dictated the need for a robust statistically optimized retrieval method. A common feature of many of these instruments is multiple channels of information with significant contribution from a small number of emitters.
Temperature Profile Measurements Using Oxygen DIAL
Authors: Korb C. Laurence , Schwemmer Geary K. , Prasad Coorg , Weng Chi Y. , Famiglietti Joseph , Flamant Cyrille N.
Published: February 2023

We describe differential absorption lidar(DIAL) measurements of the vertical temperature profile in the lower troposphere made in the oxygen A band. A 1 K accuracy, compared with a radiosonde observation made 54 km away, was obtained with a 300 m vertical resolution and a 90 s integration time.
Lidar and Radar Studies of Dynamics in the Lower Atmosphere
Authors: Meriwether John W.
Published: February 2023

A periodic wave structure with a vertical wave length of about 2 km between 12 and 19 km has been identified in Rayleigh lidar measurements at 589 nm of low altitude relative density profiles that were made by the University of Illinois group during the March/April Arecibo Initiative for Dynamics of the Atmosphere (AIDA) 1989 campaign effort. The equivalent temperature fluctuations are several degrees in magnitude. Also seen in one series of three successive nights were temperature fluctuations of about 10 °K at altitudes of 25 km with a vertical extent of 1 km. Both of these phenomena show a downward phase speed between 1 and 3 cm/s. The lower periodic structure is believed to be the same phenomenon seen previously in 430 MHz measurements of winds obtained at Arecibo Observatory. The identity of this structure remains uncertain. Cornish and Larsen [1989] and Sato and Woodman [1982a] considered this structure to be a quasi-inertial long period wave. Hines [1989] proposed instead the identification of this structure with a stationary wave system generated by orographic waves caused by the interaction of the sub-tropical tradewinds with the mountainous terrain of Puerto Rico. The higher altitude feature seen in the AIDA lidar observations is believed to be a manifestation of a region of clear air turbulence, which is known to occur in the lower stratosphere.
Spectroscopic Data for Thermal Infrared Remote Sensing
Authors: Varanasi P. , Nemtchinov V. , Li Z.
Published: February 2023

There has been extensive world-wide use of chloro-fluoro-carbons (CFC’s), especially CFC-11 (CFCl3) and CFC-12 (CF2Cl2), hydro-chloro-fluoro-carbons (HCFC’s), HCFC-22 (CHFCl2) in particular, and sulphur hexaflouride (SFg) in numerous many industrial applications.1-3 These chemicals possess either a strong ozone-depletion potential4 or a glob al-warming potential,5-7 or both, and pose a threat to the inhabitability of our planet. Recognition of this fact has led to significant curtailment, if not total banishment, of their use globally. However, as recent satellite observations8 have shown, decline in their atmospheric concentrations may not be immediate. The marked depletion of ozone which has been observed in recent years at high latitudes has made infrared remote sensing of the atmosphere an activity of high priority.8-11 The success of any infrared remote sensing experiment conducted in the atmosphere depends upon the availability of accurate, high-resolution, spectroscopic data that are applicable to that experiment. This paper presents a preliminary phase of a multi-faceted work using a Fourier-transform spectrometer (FTS) which is in progress in our laboratory. The concept of how laboratory-borne measurements can be geared toward obtaining a database that is directly applicable to sattelie-borne remote sensing missions is the main thrust of this paper which addresses itself to ongoing or planned international space missions. Spectroscopic data on the unresolvable bands of the above mentioned as well as several other man-made gases and on the individual spectral lines of such naturally present trace gases as CO2, N2O, NH3, and CH4 are presented. There is often significant overlap between the isolated lines (Fig. 1) of better known bands of the more abundant species and the weaker absorption features identifiable as bands of the currently less abundant CFCs, HCFCs, and SF6 (Fig. 2).
Analysis of Errors in Cirrus Cloud Particle Size Derivation using the Atmospheric Emitted Radiance Interferometer
Authors: Collard A.D. , Ackerman S.A. , Smith W.L. , Feltz W.F.
Published: February 2023

The University of Wisconsin's Atmospheric Emitted Radiance Interferometer or AERI (Smith et al., 1994a; Revercomb et al., 1993) operates over a wavelength interval from around 500cm-1 (20µm) up to about 3000cm-1 (3µm) at an unapodised resolution of 0.5cm-1. It has previously been shown (Smith et al., 1993; Collard et al., 1994) that this instrument can be used to measure the effective radius of cirrus cloud particles using the spectral variation of the emitted cloud radiance in one or both of the window regions observed by the AERI.
An Error Analysis for High Spectral Resolution Lidar Measurements
Authors: Eloranta E. W. , Piironen P.
Published: February 2023

The University of Wisconsin High Spectral Resolution Lidar (HSRL) provides calibrated vertical profiles of the backscatter cross section, extinction cross section, depolarization, and optical depth.1,2 Unlike values obtained from conventional lidars, these measurements do not require a priori assumptions relating backscatter and extinction cross sections and they do not involve numerically unstable inversion algorithms.
JPL-TMF Multiwavelength Aerosol Lidar
Authors: Haner David A. , McDermid I. Stuart
Published: February 2023

The JPL-TMF Lidar Facility began operation in 1985 with the completion of a XeCl excimer based stratospheric ozone DIAL system. As an adjunct to this system a Nd: YAG based tropospheric ozone and aerosol system was assembled. The tropospheric ozone system was designed to utilize the fourth harmonic (266 nm) of the Nd: YAG to produce 289 nm, 294 nm or 299 nm by SRS in the isotopic hydrogen gases. The aerosol lidar was developed using the fundamental (1064 nm) and second harmonic of the Nd:YAG (532 nm). Following the eruption of Mount Pinatubo most of the effort was put into obtaining data on the layer structure of the volcanic aerosol as a function of altitude and time on a regular basis. During this period the tropospheric ozone DIAL was not employed on a regular schedule.
Compensational Methods for Retrieving Ozone Concentration Profiles with a Multiwavelength DIAL System
Authors: Kovalev Vladimir A. , Bristow Michael P. , McElroy James L. , Alvarez Raul J.
Published: February 2023

Uncertainty in the spectral dependencies of atmospheric aerosol backscattering and extinction produces an uncertainty in the corresponding correction terms in the DIAL equation used to determine O3 concentration values, especially in turbid atmospheres where large aerosol backscattering gradients exist. Two ways exist for reducing the systematic distortion in ozone concentration profiles caused by aerosol differential extinction and backscattering, viz. i) to correct the calculated O3 profile using assumed atmospheric spectral dependencies for extinction (total scattering) and backscattering (the conventional correction method), or ii) to reduce this distortion using new methods for processing an extended DIAL signal set measured simultaneously at a number of wavelengths (the compensational method).
Passive Radiometric Measurements of Radio Refractivity in a Coastal Environment using the Atmospheric Emitted Radiance Interferometer (AERI)
Authors: Knuteson R.O. , Smith W.L. , Revercomb H.E. , Feltz W.F.
Published: February 2023

Measurements of radio refractivity have been made along the California coast with a high spectral resolution radiometer, the Atmospheric Emitted Radiance Interferometer (AERI).
Remote Sensing of CO Over the Continental US on September 12/13, 1994
Authors: McMillan W. Wallace , Strow L. Larrabee , Foutz Brian
Published: February 2023

A particular concern in tropospheric chemistry is the abundance of carbon monoxide (CO). Increasing levels of CO may lead to a decrease in the abundance of atmospheric hydroxyl (OH), which would reduce the atmosphere’s ability to scavenge other trace gases. While recent results indicate the abundance of CO has been decreasing since 1987 [Kahil and Rasmussen, 1994], prior to that time, the CO abundance was increasing. Most previous CO measurements have been limited to the boundary layer, i.e. ground stations. While widely distributed, these ground stations lack the global coverage and temporal resolution necessary to accurately assess and model the effects of CO on global tropospheric chemistry.
Microwave and Infrared Investigations of N2O5
Authors: Fraser Gerald T. , Domenech J.L. , Grabow J.-U. , Andrews A M. , Irikura K.K. , Suenram R.D. , Lovas F.J. , Hight Walker A. R. , Lafferty W.J.
Published: February 2023

Dinitrogen pentoxide (N2O5) is an important night-time reservoir for NO2 and NO3 in the atmosphere. Toon et al.1 first observed N2O5 in the atmosphere in infrared spectra recorded at sunrise by the Atmospheric Trace Molecule Experiment aboard Spacelab 3. Their results have motivated renewed interest in laboratory investigations of N2O5 to obtain accurate intensity data for modeling the atmospheric spectra2-5. Also, ab initio electronic structural calculations have been undertaken to estimate integrated infrared band intensities to compare with the experimental results6.
Retrieval of Altitude Distributions of Trace Gases from Ground-based Spectra
Authors: Connor Brian J.
Published: February 2023

Atmospheric spectra are recorded at a number of sites around the world as part of the program of the Network for Detection of Stratospheric Change (NDSC). In many cases, it is possible to derive significant information on the height profiles of the gases whose line spectra are observed. In this paper I will examine the altitude information available in two classes of measurement in routine use by the NDSC, namely microwave thermal emission and infrared solar absorption. I will outline closely related algorithms in operational use for the microwave measurements and under development for the infrared, and show selected results for both cases.
Lidar and Radar as Partners in Cloud Sensing
Authors: Eberhard Wynn L. , Intrieri Janet M. , Feingold Graham
Published: February 2023

Clouds are important to radiative transfer and climate, so information on their structure and microphysics is in great demand. The improving technology of lidars and radars can meet many of these important observational needs. Lidar and radar can individually provide valuable but limited information on cloud properties. An amalgam of measurements by lidar, radar, spectrometer, infrared radiometer, microwave radiometer, and standard meteorological measurements yields a wealth of geometrical, microphysical, and radiative information unattainable by a single instrument (Sassen 1995; Intrieri et al. 1995). In this paper we describe how simultaneous measurements by lidar and radar give complementary information on the bulk structure of clouds and synergistic information on cloud microphysical properties.
Deriving Aerosol Properties from Combined Passive and Active Measurements.
Authors: Porter John , Lienert Barry , Sharma Shiv , Cooney Tom , Clarke Antony
Published: February 2023

Various approaches have been proposed to derive aerosol optical properties from both passive and active measurements. Nakajima et al. (1983) used multi-wavelength passive measurements of atmospheric extinction and the sun's aureole to derive the aerosol size distribution. This approach assumed the aerosol index of refraction. More recently Wang and Gordon (1993) used solar extinction and full sky radiance measurements to derive the aerosol phase function and the aerosol single scatter albedo. This approach makes less assumptions about the aerosol composition but assumes that the aerosol column properties are identical over the range of sky measurements being made. LIDAR inversions include similar approaches such as Piskozub (1993) who assumed an aerosol composition and found eight wavelengths were needed to derive the aerosol size distribution. A different approach was used by Post (1996) who defined the aerosol composition and derived information on a monodisperse aerosol using ratios developed from two or more wavelengths. In general he found the wavelengths should be spaced far apart for best results. Porter et al. (1996) looked at aerosol single scatter for AVHRR channels 1 and (0.63 and 0.86 μm) for a range of realistic marine aerosol size distributions and compositions. They found side scattering angles were the best for deriving the aerosol phase function.
Measuring the Microphysical Evolution of Mt. Pinatubo Aerosols by Multiwavelength Lidar Backscattering
Authors: Post Madison J. , Grund Christian J. , Deshler Terry
Published: February 2023

From July 28, 1991 until September 26, 1993 NOAA researchers collected 45 nearly simultaneous, collocated, vertical backscatter profiles with ruby (0.693 μm) and CO2 (10.591 μm) lidars near Boulder, Colorado. We used a graphical technique (Post, 1996) to retrieve information on the microphysical nature of stratospheric aerosol particles arising from the June 15, 1991, eruption of Mt. Pinatubo in the Philippines (15.14°, 120.35°E). Normally three independent backscatter measurements are needed to recover three model size distribution parameters, such as the three lognormal parameters of number density, median radius, and standard deviation. Instead we constrained our solutions using contemporaneous, in-situ, optical particle counter (OPC)-derived, unimodal, lognormal standard deviations from the University of Wyoming’s balloonborne sounding taken 100 km to the north (Deshler et al., 1993), and then retrieved median radius and number density.
Advances in Photon Efficient Lidar and Analysis of a Multi Year Continuous Data Record
Authors: Spinhirne James D. , Scott V. Stanley , Hlavka Dennis L. , Hwang I. H. , Lee H. Sang
Published: February 2023

Until recently establishing numbers of continuously operating lidar systems to monitor all cloud and aerosol structure of the atmosphere would have meant large manned instruments and would be largely beyond the realm of feasibility. A program is now in progress for such full time atmospheric monitoring. The development of compact, eyesafe, low cost automated lidar systems that we have called Micro Pulse Lidar (MPL) is the enabling factor.1,2 The basis of the MPL instruments is a highly photon efficient design which utilizes advanced solid state components. The first MPL field instrument began operation in 1992 and in 1993 was put into full time use at the Department of Energy’s Atmospheric Radiation Measurement (ARM) program site in Oklahoma. The initial instrument was capable of detecting all clouds and some aerosol structure on a full time basis. An improved instrument was introduced last year which has significantly higher performance and is now at the Oklahoma ARM site. Copies of the instrument are being deployed to five or more field sites around the globe. These instruments will provide a unique view of cloud and aerosol structure for the atmosphere. In this paper we discuss the improvements in the instrument design, the data that the systems are producing and analysis techniques and initial results from the data.
System Accuracy of Atmospheric Observation by RIS (Retroreflector in Space)
Authors: Aoki Tetsuo , Mizutani Kohei , Itabe Toshikazu , Sugimoto Nobuo
Published: February 2023

RIS (Retroreflector in Space) is one of the sensors of ADEOS (Advanced Earth Observing Satellite), a sun-synchronous polar-orbit satellite which was launched on August 17th of 19961). RIS is a corner-cube reflector for earth-satellite-earth laser long path absorption measurements of atmospheric trace species, such as O3, CH4, HNO3, CO, and N2O, etc.2) In this experiment, a laser beam is transmitted from a ground station to RIS and the reflected light is received at the ground station and absorption spectrum of the atmosphere is measured in the round-trip optical path. The wavelength of the reflected light varies due to the Doppler shift caused by the stellite movement. Because the magnitude of the Doppler shift depends on the satellite position relative to the ground station, we can measure the absorption spectra of the atmosphere with a high wavelength resolution. We developed the measurring system with two single-longitudinal-mode transverse, electric, atmospheric (TEA) CO2 lasers3). One of the laser is used for measuring the absorption of the target molecule. The other is used for measuring the reference signals to compensate the atmospheric turbulence, variance of the transparency, and the angular denpendence of the reflectance of RIS. Vertical profiles of the atmospheric gas species can be retrieved by solving the inverse problem.4) The analysis of the real return signal from RIS will be presented.
Range Performance Modeling Of A Solid-State DIAL System Using Radar Analysis Techniques
Authors: Brock H. Irvin , Sentell James C.
Published: February 2023

The Differential Absorption Lidar (DIAL) in its several implementations has found applications in many aspects of optical remote sensing of the atmosphere, including pollution monitoring and environmental studies. Most standard formulations describing performance, however, do not allow ready evaluation of the interactions of lidar parameters, the ambient atmosphere, and the characteristics of the gas that is to be sensed. As a result, a preferred wavelength for detection of a candidate molecule, and the laser transmitter that might be most suitable for interrogation in the required atmosphere, are not always clear.
Cloud Detection and Clearing Algorithm for Simulated Measurement Of Pollution In The Troposphere (MOPITT) Instrument Data
Authors: Rokke Laurie , Gille John , Pan Liwen , Bailey Paul , Edwards David
Published: February 2023

The attenuation of radiation by clouds in the Measurement Of Pollution In The Troposphere (MOPITT) field of view will have a significant impact on the signals measured at 2.2µm, 2.3µm and 4.7µm. In a four-year cloud study by Wylie et al.(1994), using High Resolution Infrared Radiation Sounder (HIRS) data, they found only 23% of the observations were cloud free. HIRS has a field of view of 20 km which compares well to the 22x22 km field of view of MOPITT. Thus MOPITT can expect over 75% of the observations to be cloud contaminated.
Edge Technique Lidar Measurement of the Atmospheric Wind Field
Authors: Korb C. Laurence , Gentry Bruce M. , Li S. Xingfu
Published: February 2023

In this paper we present high spatial resolution lidar wind measurements with the edge technique using a ground based lidar system we have recently developed. The edge technique [1],[2] allows measurement of small frequency shifts such as the Doppler shift of an atmospheric backscattered signal from a pulsed laser. This yields a direct measurement of the wind along the line of sight of the laser beam. The edge technique can be used for high spatial resolution, high accuracy ground and airborne wind measurement as well as high accuracy spaceborne wind measurement. We show that line of sight wind profiles with a vertical resolution of 22 m have a standard deviation of 0.4 m/s for a 10 shot average. Validation data using independent rawinsonde and optical theodolite measurements show good agreement with the lidar wind measurements at the 1 m/s level. The instrument noise level for the lidar data is 0.11 m/s. This is a unique capability and provides valuable information for studies of turbulent processes in the lower atmosphere. This capability could also be used for high sensitivity detection of wind shear and microbursts in the vicinity of airports. Simulations show the edge technique can be used from satellites to obtain global wind measurements with an accuracy of the order of 1 m/s and a vertical resolution of 1 km through the troposphere. Such a system could make eyesafe wind measurements using well developed diode pumped solid state laser technology at 1.06 µm. Multi-pulse averaging would provide a spatially representative wind measurement. In addition, at ultraviolet wavelengths the Rayleigh backscatter could be used and would provide a large signal but with reduced measurement sensitivity.
Lidar Verification of Tropical Cirrus Cloud Measurements Derived from GOES-8 Data Using the CO2 Slicing Algorithm
Authors: Eloranta E. W. , Wylie D. P. , Piironen P. , Piironen A.
Published: February 2023

Cirrus clouds are thought to play an important role in determining the radiative equilibrium temperature of the earth. Their cold temperature relative to the earth’s surface and lower clouds tends to decrease the effective radiative temperature of the the earth, while their relative transparency to incoming sunshine allows heating of lower layers of the atmosphere.
Infrared Low-Cloud Detection
Authors: Hofstadter Mark , Heidinger Andrew
Published: February 2023

Traditional infrared cloud retrieval algorithms, such as the Chahine method or the CO2 Slicing technique (Chahine 1974, Smith 1968), rely on recognizing the temperature difference between the ground and the cloud tops. For a low-cloud, however, the temperature difference is small, making it indistinguishable from the surface. As part of our work for the Atmospheric Infrared Sounder (AIRS), to be flown on the EOS-PM platform, we are developing an improved technique for the detection of low-clouds. It is based upon observations of the depth of narrow water vapor lines in an atmospheric window region. Compared to traditional methods, there is an extra factor (the water vapor amount) making the signal from a cloudy column different than that from a clear column, which increases our sensitivity to low-clouds.
Water-Vapor Differential Absorption Lidar Measurements during the Baltic Sea Experiment 1996
Authors: Wulfmeyer V. , Bösenberg J. , Jansen F. , Göktaş F. , Hirsch L. , Peters G.
Published: February 2023

At the Max-Planck-Institute (MPI) a DIAL system was developed for measurements of vertical distributions of water-vapor in the troposphere. It was shown in [1], [2] that high resolution day- and nighttime measurements can be performed with a residual error caused by laser properties of less than 5%. Additionally it was demonstrated in [3] that low statistical errors of this system allow the determination of water-vapor flux profiles by combining the system with a wind profiler and using the eddy correlation method [4].
Characterization of Carbon Monoxide Measurements by Gas Filter Correlation Radiometers from Satellites
Authors: Pougatchev N. S. , Sachse G. W.
Published: February 2023

Results of carbon monoxide (CO) measurements in the atmosphere, that have been performed by the MAPS (Measurement of Air Pollution from Satellite) instrument, show that the Gas Filter Correlation Radiometric (GFCR) technique is a powerful tool for atmospheric trace gas studies [Reichle et al., 1986]. The MAPS instrument has flown several times aboard the Space Shuttle. Based on the same GFCR approach, the MicroMAPS and MOPITT [Drummond et al., 1993] instruments are scheduled for launch in 1997 and 1998. Both of these instruments are remote sensors, and hence, their retrievals should be validated through the comparison of satellite data to the results obtained by other techniques (e.g. ground-based solar spectroscopy, in situ aircraft and ground measurements, modeling results, etc.). Spatial resolution of satellite and nonsatellite measurements ranges from several meters (in situ techniques) to up to ~ 10 km (remote methods). Moreover, radiative transfer processes in the nonuniform and nonhomogeneous atmosphere make remote methods unequally sensitive to different layers of the atmosphere. Thus, to make all these results intercomparable we need an explicit procedure which relates a retrieved value by any of remote technique to the real distribution of a target gas at the moment and place of observation.
Preliminary Results of Stratospheric Ozone Layer Measurements with Improved Limb Atmospheric Spectrometer (ELAS) aboard ADEOS
Authors: Sasano Yasuhiro , Suzuki Makoto , Yokota Tatsuya , Kanzawa Hiroshi
Published: February 2023

ILAS, an instrument for monitoring physical and chemical behavior of the stratospheric ozone layer from space, has been developed by Environment Agency of Japan and installed on the Advanced Earth Observing Satellite (ADEOS), which was launched on August 17, 1996 from Tanegashima Space Center by National Space Development Agency of Japan (NASDA).
Comparing the edge filter and interferometer fringe imaging for laser Doppler wind speed measurement
Authors: McKay J.A.
Published: February 2023

The Doppler shift of lidar signals backscattered from windborne particulates can be measured with heterodyne techniques in the infrared, and with optical techniques in and near the visible. So-called “direct”, i.e., optical, detection is generally implemented with a high resolution Faby-Perot interferometer, with an imaging detector to measure the displacement of the interference fringes indicating the frequency of the laser backscatter1. An alternative method for measuring the Doppler frequency shift is based on the “edge” detector2,3, in which the signal is passed through a high resolution filter off the passband center, so that the amplitude of the signal is strongly modulated by the filter transmittance versus frequency function. Then a measurement of the signal level before and after the filter yields, via the known filter function, the signal frequency. An advantage of this approach is the replacement of the expensive and technically challenging fringe imaging detector with a pair of simple, nonimaging detectors. Because the edge filter detectors can have significantly higher quantum efficiency than an imaging detector, it may be possible for this technique to yield not only a simplification of the system instrumentation but higher Doppler measurement performance.
Laser Diode Magnetic Rotation Spectroscopy of Oxygen
Authors: Brecha R.J. , Krause D. , Pedrotti L.M.
Published: February 2023

For many years magnetic rotation spectroscopy (MRS) has been used as a sensitive detection technique for various paramagnetic molecular species. [1], [2] A great deal of emphasis has been on nitrous oxide (NO) as a molecule of interest, for example in studies of atmospheric chemistry [3]. Another common paramagnetic molecule is oxygen, of interest for example in combustion studies. We present here results for wavelength modulated MRS of the so-called atmospheric band of oxygen at λ ~ 760nm using a very compact experimental setup based on a semiconductor diode laser operating near room temperature.
Experimental Investigation of the v2 Band of Water Vapor
Authors: Tobin David C. , Strow L. Larrabee , Hannon Scott E. , Lafferty Walter J. , Olson W. Bruce
Published: February 2023

A large set of laboratory transmission spectra of water vapor within the v2 band has been collected and analyzed in order to better understand its pressure broadening characteristics. Topics considered in this study include an examination of the low J
H216O N2-broadened Lorentz line-widths, determination of the self- and N2-broadened continuum coefficients, and an examination of the near- to intermediate-wing lineshape of N2-broadened water vapor. The spectra were collected using a BOMEM FTS and a White-type multi-pass absorption cell. Details concerning the experimental set-up and data collection process can be found elsewhere [1].
Generation of 940-nm Pulsed Radiation through KD*P Optical Parametric Amplification of a CW Source
Authors: Ponsardin Patrick L. , Marsh Waverly D. , Richter Dale A. , Rodriguez Waldo J. , Barnes James C. , Browell Edward V.
Published: February 2023

When compared to the 720-nm and 820-nm water vapor absorption band, the use of the stronger absorption lines (x 20) in the 940-nm wavelength range can significantly improve differential absorption lidar measurements of the low concentrations of H2O in the upper troposphere and lower stratosphere. Finding a simple and efficient way to generate laser light at 940 nm is therefore a pressing need for NASA atmospheric science program. The directors discretionary fund (DDF) program at NASA Langley Research Center provides a mean to evaluate high risk novel technologies that hold potential for a high payoff. Using this resource, we have started the characterization of a new technique that will be used to develop a 940-nm water vapor lidar transmitter.
Water Vapor Lidar Measurements at 930 Nm Using a Tunable Optical Parametric Oscillator
Authors: McGill Matthew J. , Spinhirne James D. , Scott V. Stan
Published: February 2023

Water vapor plays a significant role in determining the global climate. Water vapor is a primary greenhouse gas and is important to the heat budget of the atmosphere. As a transporter of latent heat, water vapor helps define the dynamic structure of the atmosphere. Aerosol growth is also strongly influenced by water vapor. For these reasons, it is essential to develop methods for determining the distribution and evolution of water vapor in the atmosphere.
Developing Heavy Metal Pollution Map with Multifactor Contributed
Authors: Altan Metin , Ayyildiz Ömer , Malkoç Semra , Yazici Berna , Koparal Savaş
Published: February 2023

In this study, a detailed investigation has been conducted to understand the contamination characteristics and distributions of heavy metal pollution in terms of contributions of the heavy metal concentrations as mg/kg of Cd, Cr, Cu, Ni, Zn, Pb, Fe and Mn in the urban soil in Eskişehir city center. The amount of these heavy metals were determined from 15 soil sample points collected within urban area and every sample point included 6 separated samples for chemical analyses. The results indicated that concentration values of all metals except Ni and Cr in soils were below the risky limit pollution values. Spatial distribution maps were created and recoded, in terms of these heavy metals concentrations as contribution to heavy metal pollution in soil, through Geographical Information Systems techniques.
Low Loss, Buried Channel Polyimide Waveguides For Single Mode Interconnect Applications
Authors: Valley J.F. , Stiller M. , Dries L. , Binkley E. , Kenney J. , Nurse J. , Fujimoto H. , Das S.
Published: February 2023

The PILOT program, a joint research and development agreement between the authors' three companies, was begun September, 1992, "to further advance this technology for commercial introduction." Two questions need answering here: What is PILOT and what is "this technology?" PILOT stands for Pilot Integration of Lightwave and Optical Technology and the technology is keyed to polymeric waveguides for optical interconnects. To attain "commercial introduction" we limit ourselves to polymeric materials with the potential for inclusion in a packaged device whose cost isn't prohibitive. The emphasis on polyimides, which already may be found in advanced electronic packages, arises naturally from their well known thermal and mechanical stability. We present here some preliminary results from the evolution of a process to build buried channel, single mode waveguides in fully cured polyimides.
Integrated Optoelectronic Heterostructure Devices Composed of Crystalline Organic and Inorganic Semiconductors
Authors: Kowalsky Wolfgang , Rompf Christoph , Hilmer Bernd
Published: February 2023

Today's electronic and photonic devices are mainly based on silicon or III-V alloys. Although these materials are extremely successful as individual structures, the preparation of OEICs has not yet achieved adequate results. However, organic compounds may offer a remarkable enrichment in this field. Especially polymers and crystalline organic semiconductors are promising candidates for applications in photonic devices. Due to the compatibility of UHV deposition of organic layers with inorganic semiconductor technology, crystalline organic semiconductors are well suited for OEIC applications. Waveguides, couplers, polarization splitters, and photodetectors are fabricated from UHV-deposited organic films.
High Speed Optical Intensity modulator in a Novel Polymeric Material
Authors: Moshrefzadeh R.S. , White K.M. , Francis C.V. , Kleinschmit M. W. , Mohapatra S.K. , Boyd G.T. , Williams R.C. , Hahn K.H. , Dolfi D.W.
Published: February 2023

Polymeric materials have the potential to exceed the increasingly demanding requirements for advanced nonlinear optical (NLO) devices such as intensity modulators and electro-optic switches. The benefits offered by polymeric materials include large optical nonlinearities which can lead to lower operating voltages, and lower dielectric constants necessary for high-speed modulation. Polymeric materials can in principle also be integrated with electrical driving circuits and other optical devices such as semiconductor light sources and detectors.
Picosecond Time Resolved Studies for Laser induced Optical Modulation of Second Harmonic Generation from Organic Langmuir-Blogdett Films
Authors: Sakaguchi H. , Nagamura T. , Penner T. L. , Whitten D. G.
Published: February 2023

Organic nonlinear optical materials have been paid much attention for possessing the large second and third order susceptibilities compared to the inorganic compounds. Many researches have been made as to the development of organic molecules having the large molecular hyperpolarizabilities and the assembling techniques from organic molecules into the materials for the photonic applications so far.1) However there have been few attempts to control the optical nonlinearity by laser irradiation except for the Garito's works in which the third order optical nonlinearity of diphenylhexatriene was enhanced when it was irradiated by picosecond pulses.2)
Theory of Stark Shifts in Quantum Wells Consisting of Highly Anisotropic Molecular Crystalline Thin Films
Authors: Shen Zilan , Forrest Stephen R.
Published: February 2023

Heterostructures consisting of crystalline organic semiconductors can be layered in nearly defect-free structures due to the weak van der Waals bonding between molecules.[1] As a result of their crystalline order, these films have exhibited enormous anisotropies in both their conductive and dielectric properties.[2,3] Moreover, the relatively large exciton binding energy results in an exciton absorption peak deep in the band gap, which leads to large Stark shifts useful for optical modulation. Due to the unique electrical and optical properties of this class of materials, it is useful to understand how crystalline organic multiple quantum wells (MQWs) behave in an electric field.
Measurements of third-order nonlinear properties of polymer films using a pump-probe phase distortion method
Authors: Samoć Marek , Samoć Anna , Woodruff Maneerat , Luther-Davies Barry
Published: February 2023

The recent introduction of the Z-scan technique[1-3] has provided a simple and versatile method of determining the real and imaginary parts of a materials third-order nonlinearity, χ(3) or n2. A two-beam modification of the technique [2] allows one to also investigate nondegenerate components of the nonlinearity. The high sensitivity of the Z-scan method is due to the fact that a small phase distortion introduced by the material nonlinearity corresponds to relatively large intensity variations as measured with a small diameter aperture in the far field. We suggest that this principle can be utilized in a pump-probe geometry with lock-in detection of intensity variations to improve the sensitivity. In the suggested geometry it is also possible to perform fully time-resolved measurements using picosecond or femtosecond laser pulses. Additionally, one can investigate the dependence of the nonlinearity on the spatial frequency of the induced phase or amplitude distortion. Finally, as in the original Z-scan, there is a way of separating the real and imaginary parts of the nonlinearity.
Nonlinear M-line technic for organic guiding layer characterization.
Authors: Vitrant G. , Reinisch R. , Kajzar F.
Published: February 2023

The nonlinear M-line technic allows the easy determination of Kerr properties of organic thin films. Simple modelization tools are presented and experimental results are reported.
Fast Photorefractive Response in a Polymeric Composite Film: Kinetics of PVK/C60/DEANST System
Authors: Orczyk Maciek E. , Zieba Jaroslaw , Prasad Paras N.
Published: February 2023

Since their discovery, photorefractive materials remain in the focus of photonic research1 Photorefractive behavior has been shown to manifest itself in a wide variety of device-utilizable effects. This feature is anticipated to make photorefractive materials very important to photonic technology. These materials will find practical utility only when they are easier to process, their high electrooptic coefficients are not accompanied by high polarizability, and the tradeoff between the speed and the dynamics of the response is overcome. These are also the main limitations of the well studied photorefractive inorganic crystals! Photorefractivity has been demonstrated recently also in polymeric films.2,3 These materials offer an unique opportunity of addressing separately the limitations of inorganics mentioned above by the molecular design of a polymeric composite film.3,4 Diffraction efficiencies close to 2% and two-beam coupling gain of 4 cm-1 have already been here successfully achieved in our laboratory.4,5