bluuebunny/crossref_metadata_2025 huggingface dataset:
Recent Profiles of Atmospheric Backscatter
Authors: Post Madison J. , Weickmann Ann M. , McNice G. Terry
Published: February 2023

The prevalence of atmospheric aerosols on a global basis has recently become a topic of great importance for climatologists and for researchers attempting to establish the feasibility of satellite-based measuring systems that use aerosols as tracers, as well as for those attempting to explain the interfering effects of aerosols on their measurements. In 1981 we began acquiring a large set of backscatter profiles with our 10.6 μm wavelength pulsed, coherent lidar near Boulder, Colorado. By 1984 more than 600 profiles were archived and analyzed, and several papers1-2 summarized the findings. Between 1985 and 1988 a void occurred in our data taking because we upgraded the transceiver from a lower powered hybrid design3 to a higher powered injection-seeded design4, and because of a change in our program objectives. Fortunately during this period the Jet Propulsion Laboratory began taking similar data5. In 1987 we renewed our systematic observations at the behest of NASA for its Laser Atmospheric Wind System (LAWS) studies6, and in the fall of 1988 we traveled to the Mauna Loa volcano in Hawaii to study the clean Pacific troposphere, in conjunction with the Global Backscatter Experiment (GLOBE7) program. Concurrently, our group operated a pulsed ruby lidar8 to acquire biweekly profiles of backscatter in the troposphere and stratosphere over Boulder. Recently we coordinated data taking between the two lidar systems, and we combined our observations on one occasion with observations from the University of Wyoming’s balloon backscatter instrument9.
Passive Remote Sensing of Cirrus Clouds and Their Microphysical Properties Using 8 and 11 μm Channels
Authors: Ackerman Steven A. , Smith William L.
Published: February 2023

Recent observations during FIRE have indicated the presence of small ice crystals in cirrus clouds. The presence of this small particle mode has a significant impact on the cloud radiative properties. This paper demonstrates the feasiblility of an 8 and 11 μm channel for monitoring the frequency of occurance and the global distribution of cirrus clouds containing this small particle mode.
Study of Optical Properties For Antarctic Troposphere Cloud
Authors: STEFANUTTI L. , MORANDI M. , PEIPEI CAI
Published: February 2023

This paper presents the work on infrared emissivity and depolarization ratio of tropospheric clouds in Antarctic region (66°40'S, 140° 1' E) based on the data obtained by elastic backscattering Lidar, wide field of view IR radiometer and radiosonde.
Airborne Lidar Measurements of the Two-Dimensional Atmospheric Pressure Profile
Authors: Korb C. L. , Schwemmer G. K. , Dombrowski M. , Prasad C. R. , Walden H. , Lee H. S. , Weng C. Y. , Roytblat L.
Published: February 2023

This paper describes the first high accuracy remote measurements of the two-dimensional atmospheric pressure field. Pressure is a fundamental atmospheric state variable that is required for virtually all atmospheric applications. The vertical and horizontal structure of the static pressure field characterizes the spatial distribution of mass in the atmosphere. Horizontal gradients of pressure represent the primary physical force leading to all scales of atmospheric circulations in the horizontal dimension which includes the large-scale general circulation as well as mesoscale phenomena such as sea/land breezes.
An Unwrapped Phase Distribution Model for Speckle/Turbulence
Authors: Draper Douglas C. , Holmes J. Fred , Peacock John
Published: February 2023

Several models have been proposed for the probability density function (p.d.f.) of phase for a speckle field created by a coherent beam and a diffuse object1-5 and also for a coherent beam propagating through a random medium such as clear air turbulence6-7. The p.d.f. models for speckle as well as many of the p.d.f. models for turbulence are given for the wrapped phase since the models are based on extracting phase information from the complex field amplitudes representing the radiation. Wrapped phase refers to phase angles that are limited to principal values (0-2π radians). The phase fluctuations really represent the optical path length variations which can greatly exceed 2π when represented as phase changes. Path length variations are linearly related to unwrapped phase variations by the relationship ϕ = 2πΔL/λ where ΔL represents path length variations. Consequently in a realistic situation phase is not limited to principal values. In addition the wrapped p.d.f. expressions are mathematically complicated and it would be difficult to extend them to the case where a speckle field and a turbulence field are combined (ie. where a speckle field is propagating through turbulence). Consequently simple Gaussian unwrapped phase p.d.f. models for both speckle alone and turbulence alone and a model for the combined speckle field in turbulence using the simpler unwrapped models are proposed. It will be shown using a standard technique for calculating a wrapped p.d.f. from an unwrapped p.d.f5 that the wrapped p.d.f.’s obtained from unwrapped Gaussian models are approximately equivalent to the known wrapped p.d.f.’s for speckle phase. It will also be shown from our experimental work that the measured unwrapped phase is approximately Gaussian.
Injection Seeding a Multimode Alexandrite Laser Using a Frequency Stabilized Diode Laser
Authors: Schwemmer Geary , Addleman Shane
Published: February 2023

Narrowband, frequency stable, pulsed laser sources are required for lidar remote sensing of atmospheric temperature, pressure, water vapor, minor species, or wherever narrow spectral features are essential for the measurement. Spaceborne lidar remote sensing systems require lasers with the highest efficiency possible, due to the constraints of limited power, weight, and size. In many instances, this implies a multi-spatial mode laser system. NASA’s Laboratory for Atmospheres has developed a differential absorption lidar system using pulsed multimode alexandrite lasers to measure atmospheric temperature profiles by measuring oxygen absorption on high J lines in the A band, near 770 nm. These spectral lines have a full width of 0.07 cm-1 at one atmosphere of pressure, and a full doppler width of 0.03 cm-1. This implies a requirement on the laser frequency stability and setting of approximately 0.001 cm-1. In this paper we describe the experimental development of a frequency stabilized diode laser and its use to injection seed a pulsed alexandrite laser.
Polarization and Possible Differences in Backscatter Measurements
Authors: Anderson Richard
Published: February 2023

In the fall of 1989 a series of flights were made to compare backscatter measurements performed by different lidars and a second flight may be made in the spring of 1990. The lidars to be compared may be monostatic and bistatic systems and will transmit light of one state of polarization and analyze received light in a different state of polarization. In this paper the nature of the signals will be analyzed by a vector-matrix theory where the light is represented by (4x1) Stokes vectors and the interaction with the atmosphere is represented by a (4x4) Mueller matrix. In each apparatus a value for β, the volume backscatter coefficient, is measured and it will be sums of differences of certain components of the
β^ matrix which will depend upon the polarization properties of the laser. Pritchard and Elliott1 have performed a similar analysis for an atmospheric polarimeter but they studied a fixed target of magnesium oxide. This discussion will assume a pulsed lidar (rectangular pulse of width τ) so a thin slab of the atmosphere of thickness cτ/2 centered about Rs=c(t/2-τ/2) is examined.
Numerical Differentiation Methods for Estimating Ozone Concentration in DIAL Measurements
Authors: Zhao Yanzeng
Published: February 2023

To obtain atmospheric parameters (e.g., concentration of gas species) from DIAL (differential absorption lidar) measurements, numerical differentiation is always needed.
Particle Size Distribution Estimation From Inverse Radiative Transfer Measurements
Authors: McCormick N.J.
Published: February 2023

Equations are summarized for estimating the size distribution of particles from measurements of components of the Stokes vector for polarized radiation using a two-step inversion procedure. The inverse (Fredholm) size distribution algorithm requires that optical properties at different wavelengths be obtained from an inverse radiative transfer algorithm. The inverse radiative transfer algorithm requires that time-dependent normally-directed backscattered radiance measurements be made long after a radiation pulse illuminates an optically thick medium.
The Development of New Techniques For Remote Measurements of Atmospheric Gases
Authors: Woods P T , Jolliffe B W , Milton M J T , Mcllveen T J , Swann N R W , Stuart D D
Published: February 2023

The differential absorption lidar (DIAL) technique potentially has the ability to measure a wide range of atmospheric gases and industrial pollutants. The mobile DIAL facility developed at the National Physical Laboratory (NPL) is capable of range-resolved measurements of gases such as SO2, NO, NO2 and O3 in the troposphere [1] using visible and ultraviolet radiation. However, there is widespread interest in measuring a much broader range of gaseous pollutants which are emitted in industrial processes. These gases generally have absorption spectra in the infrared spectral region (wavelength range 2–15 μm), where DIAL measurements are much more difficult to carry out. Research aimed at developing a high-energy tunable infrared DIAL source for this requirement is outlined below. The wavelength coverage of the ultraviolet source in the DIAL facility has also been extended to address different atmospheric gases, and examples of results obtained using the NPL simultaneous infrared/ultraviolet DIAL system will be presented.
Dobson Spectrophotometer 83: A Standard for Ground-based and Satellite Total Ozone Measurements
Authors: Komhyr Walter D. , McPeters Richard D.
Published: February 2023

Dobson spectrophotometer No. 83 was established in 1962 as a standard for total ozone measurements in the United States. In 1980, the instrument was designated by the World Meteorological Organization as the Primary Standard Dobson spectrophotometer for the world. Since the early 1970’s, instrument No. 83 has been used extensively to calibrate instruments of the global Dobson total ozone station network. Calibrations of the instrument (on the Vigroux (1953) ozone absorption coefficient scale for AD wavelengths) were performed by the Langley slope method (Dobson and Normand, 1962) at Sterling, Virginia, in 1962, and at Mauna Loa, Hawaii in 1972, 1976, 1978,1979, 1980, 1981, 1984, and 1986-1989. Additionally, calibration checks on the instrument have been performed routinely since 1962 with a set of standard lamps Results of the calibrations through 1987 have been described elsewhere in detail (Komhyr et al., 1989).
The JPL-TMF Stratospheric Ozone Lidar System.
Authors: McDermid I. Stuart , Walsh T. Daniel
Published: February 2023

A laboratory has been established at the JPL-Table Mountain Facility at Wrightwood, California, from which to make atmospheric measurements. A high-power, differential absorption lidar system for measuring stratospheric (20 - 50 km) ozone concentration profiles, has been in operation at JPL-TMF since January 1988. In this paper we will present a brief description of the design, operation and data analysis methods for this system. The results obtained over the last two years will be summarized in terms of the observed seasonal variations in the ozone profile and by long-term inter-comparison with results from the SAGE II satellite instrument.

The work described in this study was carried out at the Jet Propulsion Laboratory, California Institute of Technology, through an agreement with the National Aeronautics and Space Administration.
An Assessment of Calibration Errors of SBUV Type Instruments for Measurements of Stratospheric Ozone and UV Solar Spectral Irradiance: 1970 - 1989
Authors: Heath Donald F.
Published: February 2023

A continuing series of measurements of atmospheric radiances in the Hartley-Huggins bands of ozone absorption and corresponding solar irradiance measurements have been made since 1970 by a series of 0.25 meter focal length tandem Ebert-Fastie double monochromators. An ozone inversion algorithm yields profiles and total column amounts from the ratio of atmospheric radiances/solar irradiances at 12-wavelengths in the region 250-340nm. This work discusses major sources of uncertainties in the atmospheric reflectances which are used in the ozone inversion algorithm. A summary of SBUV type instrument calibration parameters are given in Table 1.
Calibration of Long Term Satellite Ozone Data Sets Using the Space Shuttle
Authors: Hilsenrath Ernest
Published: February 2023

Trends in atmospheric ozone continue to be an environmental concern. Drifts in satellite observations are the major obstacle in the detection of changes in global ozone over the long term. Careful re-analysis of satellite ozone data along with groundbased observations have more or less corroborated photochemical models which predict ozone depletion [1]. However there remains margin of error in the observations that is as large as the trend itself.
Results From The JPL-TMF Ozone Lidar System During STOIC’89.
Authors: McDermid I. Stuart , Walsh T. Daniel
Published: February 2023

A high-power, differential absorption lidar system for measuring stratospheric (20 - 50 km) ozone concentration profiles, has been in operation at the JPL Table Mountain Observatory since January 1988. Validation of the results obtained from this system has been provided through extensive inter-comparison (STOIC’89) carried out in July/August 1989. Many instruments were involved in this campaign, including the GSFC mobile DIAL system, the SAGE II satellite instrument, ROCOZ-A rocket sondes and ECC balloon sondes, microwave radiometers, and both Dobson and Brewer column measuring spectro-photometers. The results have shown that the lidars are capable of providing high quality data and will play an important role in monitoring the stratosphere and providing correlative and ground-truth measurements for future space-based instruments such as onboard the UARS and Eos platforms.
Ozone Vertical Profile Comparisons Using the ROCOZ-A Ozonesonde
Authors: Parsons Chester L. , Barnes Robert A.
Published: February 2023

The Rocket Ozonesonde (ROCOZ) was originally developed in the early 1960’s and used for comparisons with ozone measurements from the OGO-4 satellite. In the 1970’s, measurements with ROCOZ were made in support of the BUV instrument on Nimbus-4 and the SBUV instrument on Nimbus-7. By 1982 problems with the ROCOZ payload led to an instrument improvement program at NASA Goddard Space Flight Center’s Wallops Flight Facility. Changes were made to the center wavelengths and spectral shapes of the ultraviolet filters. An integrated calibration facility was established1, and new data reduction procedures were designed2. Measurements of the repeatability of the current version of the instrument have been made2, along with a description of the design of the radiometer3. The Improved Rocket Ozonesonde (ROCOZ-A) is propelled aloft by a Super-Loki booster rocket. At rocket burnout, the instrument and its carrier coast to a nominal apogee of 70 km, where the payload is ejected for deployment on a parachute. The radiometer measures the solar ultraviolet irradiance over its filter wavelengths as it descends through the atmosphere. The amount of ozone in the path between the radiometer and the Sun is then calculated from the attenuation of solar flux as the instrument falls. In addition, radar at the launch site measures the height of the payload throughout the descent. Knowledge of the solar zenith angle allows calculation of the fundamental ozone value measured by the radiometer, which is ozone column amount as a function of geometric altitude. Ozone number density is calculated from ROCOZ-A ozone measurements as the derivative of ozone column amount with altitude.
A Microwave System for Remote Sensing of Ozone
Authors: Parrish Alan , Connor Brian J. , Tsou Jung-Jung
Published: February 2023

It has long been known that it is possible to measure stratospheric ozone and other trace constituents by ground based microwave spectroscopy (e.g. Connor et al., 1987 and references therein). We report here on an instrument that we have developed for long-term monitoring of ozone for the Network for the Detection of Stratospheric Change. The instrument was installed at Table Mountain Observatory, California, in June, 1989, and shortly thereafter participated in the Stratospheric Ozone Intercomparison Campaign (STOIC).
Table Mountain Ozone Intercomparison: Brewer Ozone Spectrophotometer Umkehr Observations
Authors: McElroy C.T. , Kerr J.B.
Published: February 2023

During the 1989 Stratospheric Ozone Intercomparison Campaign (STOIC) at Table Mountain Observatory in California, the Atmospheric Environment Service of Canada operated a Brewer Ozone Spectrophotometer to make measurements of the total column amount of ozone [Kerr and McElroy, this issue], and of the vertical distribution of ozone in the atmosphere through the use of Umkehr observations.
Tropospheric Wind Measurements by Incoherent Lidar
Authors: Abreu Vincent J. , Hays Paul B. , Barnes John E.
Published: February 2023

The Space Physics Research Laboratory (SPRL) has implemented a ground-based incoherent lidar system to measure winds in the lower atmosphere. This is a stable, high resolution system consisting of an optically contacted plane etalon, and a multi-ring anode detector to spatially scan the image plane of the Fabry-Perot. The high resolution provided by the interferometer allows the separation of the aerosol and molecular components of the backscattered signal. The doppler shift of the aerosol component is then used to determine the line of sight wind altitude profile in the troposphere and stratosphere. Here we describe the High Resolution Doppler Lidar (HRDL) developed at SPRL, and present the system characteristics and sample measurements.
Microwave observations of precipitable water
Authors: Tjemkes Stephen A. , Stephens Graeme L.
Published: February 2023

Global warming is a contemporary topic of great scientific and social interest. Current models predict a temperature increase as large as 4 K when the atmospheric concentration of carbon dioxide is doubled. The coupling of the hydrological cycle with the initial forcing by carbon dioxide appears to be crucial in these calculations. At present however, it is not evident that the hydrological cycle is correctly modeled. And a comparison of the various components of this cycle with observations is needed. In this presentation observations are presented which could be used to validate the water vapor distributions computed by general circulation models. A method for retrieving precipitable water from observations by the Special Sensor Microwave/Imager (SSM/I) over the global oceans is described. Preliminary results of the retrieved precipitable water and near surface wind velocities for September 1987 are described
Raman Lidar Measurements of Temperature in the Troposphere and Lower Stratosphere
Authors: Ferrare R. A. , Whiteman D. , Melfi S. H.
Published: February 2023

This report will briefly describe a combined Raman, Rayleigh-Mie lidar developed at NASA/GSFC which measures temperature in the troposphere and lower stratosphere. Temperatures are retrieved using the rotational-vibrational Raman signal scattered by nitrogen molecules in an extension of the technique discussed by Melfi and Whiteman (1986). While the previous technique assumed negligible aerosol extinction and therefore was limited to the upper troposphere and stratosphere, the method described here uses the Rayleigh-Mie and Raman signals to determine aerosol extinction and is therefore used to extract temperatures through much of the troposphere.
A Balloon Borne Ozone Profiler with Variable Footprint
Authors: Heaps William S. , Guthrie Paul D.
Published: February 2023

The global view of the earth provided by satellite borne instruments is crucial if we are to understand and respond correctly to the growing number of environmental threats posed by man's varied activities upon the planet, however, in order to made the fullest use of the information gleaned from satellites it is necessary that the performance of these space borne sensors can be verified. An instrument in space is subject too many environmental extremes--heat, cold, solar and cosmic radiation to name a few. Any or all of these have the potential to affect the performance of the satellite instrument producing changes in the calibration which destroy the utility of the long term view of the globe otherwise afforded.
Prelaunch Calibration of the Shuttle Solar Backscatter Ultraviolet (SSBUV) Spectrometer for STS-34
Authors: Cebula Richard P. , Hilsenrath Ernest
Published: February 2023

The Shuttle Solar Backscatter Ultraviolet (SSBUV) spectrometer has been calibrated for its maiden voyage on the 18 October 1989 flight of the orbiter Atlantis (STS-34). Three separate preflight calibrations, performed during the period October 1988 through May 1989, showed a prelaunch radiometric calibration repeatability on the order of 1% or better.
Balloon-borne Measurements of the Vertical Propagation of Thermal IR Radiance in a Tropical Atmosphere
Authors: Hagan Denise E.
Published: February 2023

Overview. Radiometric measurements of the upwelling 11 micron flux from the ocean surface through a tropical atmospheric boundary layer have been made from an aerostat platform to test a radiative transfer model prediction of the outgoing sea surface radiance. The radiance measurements were made for the spectral bandpass 900 cm-1 to 980 cm-1 using an infrared radiometer having an instrument precision of 0.002°C and an absolute accuracy of 0.1°C. The radiometer was mounted beneath an aerostat tethered to the USCG ship Windward Sentry, and flown over the ocean near Cape Canaveral, Florida in late October, 1989. Other atmospheric measurements collected simultaneously near the location of the radiometer included dry and wet bulb temperatures and total pressure. Sea surface and air surface temperatures were measured from the ship's stern. Two profiles of radiance are examined in this presentation. The first profile was obtained in tropical atmospheric conditions; the sampling technique involved a slow (45 minutes) vertical ascension of the aerostat to a maximum tether altitude of about 2300 feet. Radiometric measurements for the second profile were made a few days later in atmospheric conditions almost 10 degrees cooler than the first day. Standard line-by-line radiative transfer calculations of the outgoing flux were carried out using the actual values of air temperature, water vapor content and atmospheric pressure measured for each day. The observed and calculated profiles, which will be presented during the poster session, show very close agreement (to within a few percent). The results show that there is no significant error in present empirical expressions for the water vapor continuum absorption (for the 900-980 cm-1 spectral range) which are based on the laboratory measurements given by Burch* (1970) and Burch and Alt** (1984). This conclusion is shown to depend on the selection of appropriate weighting functions to characterize the mean water vapor partial pressure and temperature over the observing path.
Measurement of the Water Vapor Continuum Absorption Coefficient between 800-1200 cm-1
Authors: Fukabori Masashi , Aoki Tadao
Published: February 2023

Extensive experimental studies have been made to determine the water vapor continuum absorption coefficient in the atmospheric window region.1-7 However, the values of the continuum absorption coefficient are still largly uncertain. Experimental results by Burch’s group are basic data for LOWTRAN series and FASCODE2, though the different continuum absorption coefficients are reported from their earlier and recent experiments. Our purpose is to determine the water vapor continuum absorption coefficients from sky emission spectra.
Retroreflector-In-Space for Japanese Satellite ADEOS: Earth-Space-Earth Laser Long-Path Absorption Measurements of Atmospheric Trace Species
Authors: Sugimoto Nobuo , Minato Atsushi , Sasano Yasuhiro
Published: February 2023

Laser long-path absorption spectrometry is one of the most sensitive methods for measuring atmospheric trace species. This method can be used for measuring extremely low concentration trace species which cannot be detected by single-ended differential absorption lidars.
High Resolution Infrared Absorption Spectroscopy of Atmospheric Constituents
Authors: Rinsland Curtis P.
Published: February 2023

Remote sensing using high-resolution absorption measurements of the Sun in the infrared (1 to 20 μm region) has greatly increased our knowledge of the chemical composition of the Earth's atmosphere. This contribution is the consequence of the large number of minor and trace telluric molecular constituents with strong absorption features in the infrared and instrumental improvements that have permitted observations from the ground, aircraft, balloons, and space with steadily increasing sensitivity and accuracy.
The High Resolution Dynamics Limb Sounder (HIRDLS) on the Earth Observing System
Authors: Gille John C. , Barnett John J.
Published: February 2023

As humanity embarks on the study of global change, many new scientific problems have emerged, requiring improved capabilities for observing the middle atmosphere from the tropopause region into the mesosphere. These include the need for improved horizontal and vertical resolution, an enhanced ability to observe the region around the tropopause, and the ability to observe more interrelated species. Here the scientific objectives of the HIRDLS experiment, a multichannel limb viewing infrared radiometer intended for flight on the A platform of the Earth Observing System, will be presented, followed by a brief description of the instrument. Results of simulating the performance of HIRDLS will be presented. They show that the results will provide data from the upper troposphere to the mesopause, with resolution and precision not previously achieved, for temperature and 10 trace species, as well as aerosols. These results will provide data with which to study several important global change problems.
Non-LTE Modelling for the Retrieval of CO Abundances from ISAMS Measurements
Authors: López-Valverde M. A. , López-Puertas M. , Marks C. J.
Published: February 2023

The study of CO in the terrestrial middle atmosphere is of considerable interest since it plays an important role in many photochemical processes involving species like OH and O3. It can also be a very good tracer, especially in the mesosphere where its photochemical lifetime becomes longer1,2. Its volume mixing ratio is very variable in altitude, latitude and time3 because of the variety of production and loss mechanisms. ISAMS is the only instrument on board UARS which measures CO atmospheric emission at 4.7 μm. This emission originates from the first vibrationally excited level of the CO molecule which is in non-LTE in the whole mesosphere4,5,6. Also the increase with height of the concentration of CO in the mesosphere gives rise to the important contribution of mesospheric levels to limb radiances at stratospheric tangent heights. Therefore, knowledge of the non-LTE source function is essential before CO abundances in the middle atmosphere can be retrieved from 4.7 limb radiances. We describe here the non-LTE model we have developed to compute the population of CO(1) and the way in which these calculations will be incorporated into the ISMAS retrieval scheme.
Global Three-Dimensional Distribution of LAWS Observations Based Upon Aerosols, Water Vapor and Clouds
Authors: Wood S. A. , Emmitt G. D. , Wood L. S.
Published: February 2023

A space-based Doppler Lidar Atmospheric Wind Sounder (LAWS) has been proposed by NASA as a facility instrument for the NASA Earth Observing System. Simpson Weather Associates, Inc. has developed LAWS Simulation Models (LSM) that are coupled with Global Circulation Models (GCM) to evaluate the potential impact of global wind observations on the basic understanding of the earth’s atmosphere and on the predictive skills of current forecast models (GCM and regional scale). This paper uses the LSM to examine the three dimensional distribution of LAWS’ observations over the globe. Such a study must consider the effects of atmospheric aerosols, molecular attenuation of the lidar signal, opaque clouds, and the presence of thin cirrus clouds.
Theoretical Computation of Trace Gases Retrieval Random Error from Measurements of High Spectral Resolution Infrared Sounder
Authors: Huang Hung-Lung , Smith William L. , Woolf Harold M. , Theriault J.M.
Published: February 2023

The purpose of this paper is to demonstrate the trace gas profiling capabilities of future passive high spectral resolution (1 cm-1 or better) infrared (600 to 2700 cm-1) satellite tropospheric sounders. These sounders, such as the grating spectrometer, Atmospheric InfRared Sounders (AIRS) (Chahine et al., 1990) and the interferometer, GOES High resolution Interferometer Sounder (GHIS), (Smith et al., 1991) can provide these unique infrared spectra which enable us to conduct this analysis.
Aerosol Retrieval over Land from AVHRR data
Authors: Vermote Eric , Kaufman Yoram J. , Holben Brent , Tanré Didier , Kalb Virginia
Published: February 2023

A family of methods for aerosol retrievals are based on the monitoring of the radiance from a dark target of known reflectance (ocean) which is inverted in an appropriate aerosol model to obtain the correct aerosol optical thickness for that surface reflectance. This approach, begun over oceans using Landsat MSS [1], developed into a routine NOAA product using weekly AVHRR data sets [2]. This ocean method discussed above dense, dark green vegetation (covering 30% of land surface) replaced the ocean as the dark target and showed good results for forests near Chesapeake Bay using Landsat MSS [3]. In this paper we shall discuss the method (section 2) and validation (section 3) of this technique to the AVHRR incorporating the 3.75 μm channel not available on the Landsat platform. Several applications and comparison with ground measurements are given though a sensitivity study of the expected accuracies for the AVHRR.
Retrievals of Sea Surface Temperature from Multiple Passband Radiances in the 10 to 12 Micron Region
Authors: Hagan Denise E.
Published: February 2023

It is well known that water vapor is the principal absorber of outgoing surface radiation in the 10 to 13 micron spectral region commonly used for infrared remote sensing of SST. This attenuation of the radiation is almost entirely due to the effects of the water vapor continuum (ie, the observed absorption which is in excess of that due to individual spectral transitions that occur within the atmospheric 'window'). During the past twenty years, laboratory and some field studies have resulted in empirical descriptions of the continuum extinction (Roberts et al, 1976; Clough et al., 1989). These studies have shown that the continuum absorption is approximately proportional to the square of the water vapor density, and that the absorption obeys a negative temperature dependence.
GLitter Absorption Etalon Spectrometer (GLAES) concept for remotely sounding minor and trace molecular species
Authors: Kumer JB , Benson RS , Sterritt LW , Rosenberg WJ , Roche AE
Published: February 2023

High spectral resolution (≈.005 to .05 cm–1) ground based solar infrared absorption experiments have demonstrated capability to sound atmospheric species. A sample of these includes HCN, C2H2, C2H0, CH4, NO2, and HCl from solar absorption spectra obtained in the 3 to 3.5 jam region. The GLAES concept is aimed at obtaining similar absorption spectra in light that passes through the atmosphere and is reflected from the earths surface back out to the satellite. This would enable the solar absorption technique to be expanded from a limited number of ground base cites to satellite borne global mapping. Spectral resolution of the order a few hundredths cm-1 is necessary to discriminate against absorption continuua introduced by the reflecting media and the atmosphere, and will enhance identification of the target molecular species absorption lines. The GLAES approach involves tuneable piezo-electric etalons and a CVF to obtain spectra across an interval ≈ 1 cm-1 any where on the range ≈ 2.5 to 4.5 um, with a scan time of ≈ 0.1 s. Several hundredths cm-1 resolution can be achieved with a 7.7 mrad field of view for example. The corresponding perpendicular footprint is ≈ 5.6 km from 700 km polar orbit, and ≈ 275 km from geosynchronous. The most effective mode of operation is to use a front end mirror to point at the solar specular point on a body of water (lakes, ocean, etc.) larger than the footprint. At 3.5 μm and 60 deg angle of solar incidence for example the glitter radiance (≈ corrected for continous atmospheric absorption) is of the order 3.5×10–7 w/cm–2 sr–1(cm–1)–1. This is considerably larger than 290 K black body radiance ≈ 1.9×10–8 w/cm–2sr–1(cm–1)–1, or solar Lambertian (typical terrain) reflected radiance of ≈2.2×10–8 w/cm–2sr–1(cm–1)–1. By using the solar glitter and 4 inch aperture/etalon diameters a S/N ≥ 100 per spectral sample can be achieved by using an InSb PV detector cooled to ≈ 65 K. This S/N is more than adequate to detect 1 % absorption lines (which typically include several spectral samples). The detector cooling could be achieved by Stirling cycle refrigerators, or by passive radiation for appropriate satellite operations/accomodation. Modest spectrometer cooling of the order ≈ 160 K is required. No optics cooling is required. A sun synchronous near-polar orbit at altitude ≈ 700 km, with orbital plane ⊥ to the direction to the sun is an interesting candidate for GLAES deployment. It would provide for nearly ideal viewing into ≈ 75 degree solar incident glitter, for nearly continous coverage, and is the best low altitude orbit for passive radiative cooling. More instrument description, simulated solar glitter absorption spectra, and estimates for the retrievability of mixing ratio and/or column density for selected molecular species will be presented.
Spectroscopic Considerations for the Atmospheric Infrared Sounder (AIRS)
Authors: Straw L. Larrabee , Hannon Scott E.
Published: February 2023

The Atmospheric Infrared Sounder (AIRS) is a high spectral resolution nadir sounder scheduled to fly on EOS-A.1 AIRS primary goal is temperature and humidity sounding, although a large number of other products will be derived from AIRS radiances. The instrument is based on a grating spectrometer that operates from 650 to 3000 cm–1 with a resolving power of 1200. This results in a spectral resolution ranging from 2.5 cm–1 at 3000 cm–1 to almost 0.05 cm–1 at 650 cm–1. Instrument noise equivalent temperatures on the order of 0.25K or better are expected.
Detection Sensitivities and Measurement Accuracies for Tropospheric Species Using the TES Instrument on EOS/B
Authors: Margolis J. S. , Martonchik J. V. , Beer R.
Published: February 2023

The EOS-B/TES (Tropospheric Emission Spectrometer) instrument is a Fourier Transform spectrometer which views the earth's atmosphere in either a nadir mode, with a spectral resolution of 0.1 cm–1, or in a limb sensing mode, with a spectral resolution of 0.025 cm–1. The spectral region covered is between 600 and 4350 cm–1 as listed in Table 1. The broad spectral coverage and the radiometric calibration of this instrument allow the determination of the atmospheric temperature profile, surface brightness temperature and concentration profiles of the minor infrared active gases. The instrument simultaneously views the atmosphere in 4 separate spectral regions; each region possesses a series of filters which may be programmed into position (see Table 1) and a separate focal plane with a linear array of 32 adjacent detectors (only the central 16 are used at the limb). The optical arrangement allows viewing in the limb mode with a 2 x 20 km field of view for each detector at the tangent point with the long dimension being horizontal and the 16 detectors stacked vertically. In the nadir mode the footprint of each of these detectors is 0.5 by 5.0 km or 5 by 50 km depending on the selected field optics. The spectrometer optics are cooled and the detector arrays are selected such that the signal/noise in each of the narrow bands is essentially source limited.
Remote Sensing of the Atmosphere Using Far-Infrared Emission Spectroscopy
Authors: Carli Bruno
Published: February 2023

The principal characteristics of far-infrared (FIR) remote sensing of the atmosphere are: (i) the use of optical techniques at very long wavelengths, (ii) the fact that a relatively cold source, such as the atmosphere, can be observed in emission in the Rayleigh-Jeans region of the black-body distribution, (iii) the fact that many minor stratospheric constituents display a pure rotational spectrum in this region.
Infrared Spectroscopic Observations of the Polar Stratosphere
Authors: Coffey M.T. , Mankin William G. , Toon Geoffrey C.
Published: February 2023

The discovery by Farman et al. (1985) of a large springtime depletion of ozone over Antarctica and its subsequent confirmation as a large scale progressive phenomenon has led to intensive theoretical and experimental investigations in both polar regions to determine the cause and extent of this effect.
Intercomparison of Fit and his Spectral Measurements with Fascode Calculations in the 7 to 11.8 μm Region
Authors: Thériault J. M. , Revercomb H. E. , Knuteson R. O. , Smith W. L. , Huang H.-L.
Published: February 2023

A new series of long range atmospheric transmission measurements has been performed in the 3-12 μm spectral region (1 cm-1 resolution) over a 5.7 km horizontal path using the Fourier Interferometric Transmissometer1 (FIT). An important purpose of this experiment is the validation of atmospheric transmission models in conditions of low ambient temperature for which very few experimental data exit. Preliminary comparisons with FASCOD22 predictions has revealed a level of agreement such that the residual spectroscopic signatures from the difference between the model and measurements are difficult to validate because of experimental uncertainties. To pursue this investigation, complementary information was needed. The High resolution Interferometric Sounder3-4 (HIS) measurements have provided a very accurate source of additional information (absolute brightness temperature error less than 0.5 K). The analysis of uplooking and downlooking radiance measurements with the HIS are particularly relevant to this transmission study because it involves vertical propagation through cold and dry atmospheric layers.
Global Middle Atmospheric (20-100 km) Temperatures Derived from Satellite Ultraviolet, Visible, and Near-Infrared Limb Profiles of Rayleigh Scattering
Authors: Clancy R. Todd , Rusch David W.
Published: February 2023

We describe a simple and accurate satellite-based technique for measuring temperatures throughout the Earth's middle atmosphere, based upon limb profile observations of Rayleigh scattered sunlight. An example of the precision and accuracy of this technique are two analyses limb radiances from the Solar Mesospheric Explorer, which provided a global climatology of temperatures in the poorly sampled mesospheric region from 60-90 km altitude (Clancy and Rusch, 1989); and more recently for the upper stratosphere (Clancy and Rusch, 1991). The SME mesospheric temperatures were derived from ultraviolet (265, 295 nm) limb radiances, which lead to optimum signal-to-noise ratios for measurement of Rayleigh scattering within the low density mesosphere. In figure 1, we reproduce (from Clancy and Rusch, 1989) a limited comparison of SME mesospheric temperatures with SAMS and French lidar observations (Chanin et al., 1987) at an altitude of 65 km and a latitude of 45°N. We also reproduce, in figure 2, the four-year (1982-1986) SME temperature trends for the 60-90 km altitude region.
High altitude lidar observations of density and temperature for four seasons
Authors: Meriwether John W. , Dao Phan D. , McNutt Capt. Ross , Davidson Gilbert , Moskowitz Warren
Published: February 2023

We review and summarize the measurements and analysis of the atmospheric density data obtained by Rayleigh lidar soundings at Wright Patterson AFB in five campaign periods covering the four seasons of 1989/1990 from summer to spring. The Rayleigh lidar system combined a 14 watts XeF laser with a 2.54 m mirror telescope receiver. A total of 18 nights is included in these measurements with each night series of measurements lasting typically 3 to 5 hours. The altitude coverage for these results extends from 40 to 90 km, and the precision of these results within the middle atmosphere is extraordinarily high. It was of the order of 0.1 % for density and 0.3 K for temperature for data averaged over 30 minutes at 50 to 60 km. The density precision for this data at 90 km for 3 km resolution and 15 minutes averaging was about 5% to 8% depending upon the quality of the seeing at the time of the observations. The large collecting area of the telescope receiver combined with the powerful laser transmitter produces a lidar system of greatly enhanced sensitivity when compared with most other systems in use today.
Ozone monitoring by the MRI Mark II Mobile Lidar
Authors: Fujimoto T. , Uchino O. , Mizuno Y.
Published: February 2023

The Lidar was developed for the purpose of measuring stratospheric ozone in 1988 at Meteorological Research Institute (MRI). Using this system, temperature and aerosols can be measured simultaneously. Ozone concentrations are closely related to temperature and aerosols in the stratosphere. The retrieval of ozone concentration is based on the differential absorption lidar (DIAL) technique using at least two different laser lines.
353 NM Lidar Measurements of the Mt. Pinatubo Aerosol Cloud
Authors: McGee Thomas J. , Gross Michael R. , Singh Upendra
Published: February 2023

The NASA/GSFC mobile stratospheric lidar has been operating at GSFC from September 1991 as part of the UARS correlative measurements campaign. The experiment's principle goal is to make profile measurements of stratospheric ozone between 15 and 50 km. Ozone concentrations are obtained using the DIAL technique where 308 nm is the on-line wavelength and 353 nm is the line less absorbed by ozone. A more complete description of the system, including a report on recent improvements, is given in McGee et. al.(1991).
Optical Depth of Pinatubo Dust Layers Over Boston, MA
Authors: Garner R.C. , Koenig G.G.
Published: February 2023

We present the results of optical depth calculations of Pinatubo dust layers observed over Boston, MA using a doubled Nd:YAG, elastic backscatter lidar.
Stratospheric aerosol measurements with a combined Raman elastic-backscatter lidar
Authors: Ansmann Albert , Wandinger Ulla , Schulze Christoph , Weitkamp Claus , Michaelis Walfried
Published: February 2023

Measurements of geometrical and optical properties of the stratospheric aerosol layer have been performed at GKSS Research Center in North Germany (53.5 °N, 10.5 °E) since August 1991. A combined Raman elastic-backscatter lidar with a 308-nm XeCl excimer laser as the radiation source is used. It allows the separate, independent determination of the particle extinction coefficient (from the nitrogen Raman signal profile, Ref. 1) and the particle backscatter coefficient (Rom the elastic-backscatter-to-Raman signal ratio, Ref. 2). Thus, also the extinction-to-backscatter, or lidar, ratio is determined. It provides information about the size range of the stratospheric sulfuric acid droplets. Measurements of the lidar ratio are of importance also for the calculation of the aerosol optical depth from elastic backscatter signals using the Klett method (Ref. 3).
Lidar Measurement of Stratospheric Pinatubo Aerosol at Na D2 Wavelength
Authors: She C. Y. , Chen H. , Yu J. R.
Published: February 2023

Stratospheric aerosol layers resulting from the transport of Pinatubo emission have been observed in the recent months by a Na lidar at Fort Collins, CO.
A preliminary look at early observations of the UARS particle environment monitor
Authors: Winningham J.D. , Sharber J.R. , Frahm R.A. , Burch J.L. , Biard J.C. , Black R.K. , Andrews J.P. , Baker N. , Nightingale R.N. , Chenette D.L. , Vondrak R.R. , Imhof W.L. , Gaines E.E. , Robinson R.A. , Potemra T.A. , Bythrow P.F. , Anderson B.J. , Rees M.H. , Lummerzheim D. , Reid G.C. , Roble R.G. , Clauer C.R. , Banks P.M.
Published: February 2023

Abstract and summary are not available.
Lidar measurements of volcano Pinatubo aerosol above Tsukuba, Japan
Authors: Hayashida S. , Sasano Y. , Nakane H. , Matsui I.
Published: February 2023

Stratospheric aerosol profiles observed by the lidars in NIES, Tsukuba, Japan will be presented. A large enhancement of stratospheric aerosol amount will be shown.
Lidar measurements of the evolution of the Mt Pinatubo aerosol cloud over Melbourne, Australia (38°S)
Authors: Young Stuart A. , Patterson Graeme R. , Manson Peter J.
Published: February 2023

The CSIRO Division of Atmospheric Research lidar has recently been upgraded with a 10 pps QuantaRay GCR11 Nd:YAG laser. Operation is now possible at both 532nm and 355nm and is planned at 1064nm once the upgrade has been completed. Gating circuits for the new PMT detectors allow weak signals from long ranges to be studied by blanking the strong signals from short ranges, and a low-pass anti-aliassing filter has been incorporated to allow accurate digitisation of the noisy signal at low sampling rates by the digital oscilloscope. The data acquisition software has been extended to allow the use of the signal averaging capability of the National Model VP5740A digital oscilloscope.
Measurements with a ground-based lidar network during ICE’89
Authors: Ansmann Albert , Bösenberg Jens , Elouragini Salem , Flamant Pierre H. , Klapheck Karl Heinz , Linné Holger , Loth Claude , Menenger Louis , Michaelis Walfried , Riebesell Maren , Senff Christoph , Thro Pierre-Yves , Wandinger Ulla , Weitkamp Claus
Published: February 2023

During the Intensive Field Operation (IFO) of the International Cirrus Experiment 1989 (ICE’89), four ground-based lidar systems were operated in a mesoscale network (cf. Fig. 1) in the German Bight to investigate geometrical and optical properties of cirrus cloud fields. The arrangement in an array with distances of roughly 75 km between the stations allowed the discrimination between local features and more general properties of cirrus. The lidar systems were technically quite different and in particular used different wavelengths, as they had been designed for different purposes long before ICE. The key features of each system are summarized in Table 1 together with the quantities that could be measured during the ICE’89 campaign.
Ground-based Microwave Spectroscopy of the Middle Atmosphere
Authors: Connor Brian J.
Published: February 2023

Ground-based microwave measurements of middle atmosphere constituents have made important contributions over the years. Among these are the most extensive series of mesospheric water vapor measurements to date1, the observation that antarctic ozone depletion does not extend to the upper stratosphere2, the only extant measurement of the diurnal variation of ClO3, the first observation of the diurnal variation of mesospheric ozone4, the first observation of very low concentrations of N2O in the polar vortex5, and the first detection of enhanced ClO in the antarctic lower stratosphere6.