bluuebunny/crossref_metadata_2025 huggingface dataset:
The Variability of Upper Tropospheric Water Vapor as Seen by Sage II
Authors: Chiou E.W. , McCormick M.P. , Chu W.P. , Rind D. , Larsen J.C.
Published: February 2023

The Stratospheric Aerosol and Gas Experiment II (SAGE II) launched on the Earth Radiation Budget Satellite (ERBS) in October 1984 has retrieved vertical profiles of water vapor from limb absorption solar occultation measurements at 0.94 microns. The experiment has produced a new multi-year global water vapor data set that is being archived at NSSDC. The importance of SAGE II water vapor measurements has been discussed by several investigators (McCormick, 1991; Larsen et al., 1991; Chiou et al., 1990; Chiou et al., 1991; Oltmans et al., 1991; Rind et al., 1990). It has been demonstrated by Rind et al (1991) that the study of SAGE II data has led to the confirmation of positive water vapor feedback in climate models.
Combined Infrared Emission Spectra and Radar Reflectivity Studies of Cirrus Clouds
Authors: Palmer A. J. , Matrosov S. Y. , Uttal T. , Martner B. E. , Lynch D. K. , Chatelain M. A. , Hackwell J. A. , Russell R. W.
Published: February 2023

This paper reports the first collaborative application of a unique prism infrared spectrograph1-3 with other cloud sensing instrumentation directed to understanding the longwave radiative properties of cirrus clouds. The primary measurement reported here is the slope of the emission spectrum of a cirrus cloud in the 10-12 μm atmospheric transmission window. This measurement together with simultaneous cloud radar reflectivity and temperature measurements were used to infer cloud ice crystal size.
Extinction Measurements in the Lower Atmosphere with CO2-Lidar
Authors: Hågård Arne , Persson Rolf
Published: February 2023

With the intention to develop a model for IR-extinction in slant paths in the lower atmosphere, we perform measurements with a CO2-lidar. We intend to measure profiles of the aerosol extinction coefficient and to relate the parameters of such profiles to weather parameters and the irradiation, which influences the boundary layer dynamics. Our primary application is range prediction for IR-imaging systems but the results may also be useful for radiation balance studies in weather modelling. Earlier measurements with a horizontal transmissometer have provided data for a model which relates aerosol extinction in the 0.5 - 15 μm range to weather parameters. Ref. Nilsson (1986). We hope to be able to extend the model to slant paths by use of lidar data.
Measurements of Backscattering Efficiency at Different Wavelengths in the Near-Middle I.R. (#)
Authors: Colao F. , Fantoni R. , Giorgi M. , Moliterni A.G.G. , Palucci A. , Ribezzo S. , Van der Steen H.J.L.
Published: February 2023

Two different Lidar set-ups placed in the same area (Frascati) have been used to measure the absolute backscattering efficiency in the near I.R. as a function of transmitter wavelengths in the range 1-10 μm. The set-up built for backscattering measurements in the near I.R. (1- 3 μm range) is based on Raman shifting the Nd:YAG laser radiation and its main features are listed in Table 1. The existing CO2 Lidar station [1] has been used to take data around 10 μm. Horizontal calibration has been performed for both the set-ups.
Global-Fit Analysis of BIC 1 Stratospheric Far-Infrared Emission Spectra
Authors: Dinelli B.M. , Carlotti M. , Valboni A. , Carli B.
Published: February 2023

High-resolution far-infrared emission spectroscopy of the stratospheric media provides a sensitive tool for the measurement of the concentration profiles of minor stratospheric species.
Using ’Dial’ To Measure Freeway Traffic NO2 Emissions
Authors: de Jonge C. N. , Bergwerff J. B. , Swart D. P. J.
Published: February 2023

The DIAL technique (Differential Absorption Lidar) is widely used to measure concentrations of trace constituents in the atmosphere and derive concentration profiles or distributions. Several authors have applied the technique to obtain one or two dimensional concentration distributions of air pollutants such as SO2, NO, NO2 and O3 [1,2,3]. An important application of the DIAL technique is model validation. In this study, a mobile scanning NO2 DIAL system is used to measure NO2 concentrations at a freeway in order to validate the NO2 emission parameter of the Dutch ’CAR’ model (Calculation of Air pollution from Road traffic); this model is used to estimate air pollution from traffic for comparison with regulatory limits.
The U.S. EPA airborne UV-DIAL system
Authors: Moosmüller H. , Diebel D. , Bundy D. H. , Bristow M. P. , Edmonds C. M. , Turner R. M. , Kovalev V. A. , Haas R. P. , McElroy J. L.
Published: February 2023

A compact airborne downlooking lidar system has been developed at the Environmental Protection Agency in Las Vegas. This differential absorption lidar (DIAL) has been designed to simultaneously measure range-resolved concentrations of ozone (O3) and sulfur dioxide (SO2) in the lower 3 - 4km of the troposphere, together with an indication of the aerosol distribution.
Remote Sensing of Depolarizing Media: Optimal Transmission and Reception
Authors: Kostinski Alexander B.
Published: February 2023

Partially polarized light is commonly described in terms of either coherency matrix or the four Stokes parameters. The latter description is adopted here. Consequently, the effects of a depolarizing media on the state of polarization of a propagating light are conveniently described by the so called 4X4 Mueller matrix (operator)[1,2,3].
Multiple Scattering by The Side Looking Lidar
Authors: Benayahu Yair , Fastig Shlomo , Cohen Ariel
Published: February 2023

It is accepted that the contribution of multiple scattering in Lidar measurements from optically dense media causes difficulties in the interpretation of the Lidar signal usually based on a single-scattering approximation(1). This is due to the fact that most methods used in the past for inferring particle sizes from measurements obtained by a Lidar, were based on spectral or angular single scattering measurements(2). On the other hand the multiple scattering itself provides an additional piece of information when it can be separated from the single-scattering contribution.This additional information is used below to deduce the cloud droplet size distribution function.
Lidar Measurements under the Experimental Cloud Lidar Pilot Study (ECLIPS)
Authors: Pal S. R. , Steinbrecht W. , Carswell A. I.
Published: February 2023

The ECLIPS [1] program has been established to provide an opportunity to study clouds with a vertically pointing ground-based lidar simultaneously with satellites observing the same cloud system from above. Our typical lidar measurement time series is about 3 hours duration encompassing a satellite overpass. Several months of such measurements have provided us with a large set of cloud data. We have completed an initial development of the analytical methodologies to examine such large amounts of lidar data to extract information on cloud physical and optical parameters. At present our activities under ECLIPS program are already yielding considerable insight into cloud behaviour which otherwise is difficult to determine with conventional means.
Tropospheric-Ozone Measurements with a UV Lidar System
Authors: Carnuth W. , Kempfer U. , Lotz R. , Trickl T.
Published: February 2023

Ultraviolet (UV) lidar measurements of ozone have proven to possess a high level of reliabilty in the stratosphere. For measurements in the troposphere, however, a number of technical modifications is necessary. This is the conseguence of the lower ozone densities, which reguire the use of shorter, more strongly absorbed wavelengths than commonly applied in stratospheric systems, as well as of the enormous dynamical range of the backscattered light intensity.
Typhoon Behavior Appeared on Toms Data
Authors: Takeuchi Nobuo , Suzuki Makoto , Hiruma Fumihiko , Matsuda Manabu , Tsuchiya Kiyoshi
Published: February 2023

Ozone is a good tracer of the stratospheric atmospheric motion due to its long lifetime. There ozone is photochemically generated in the upper stratosphere, and is transported into the troposphere, where the Ozone is mainly removed. The satellite ozone sensor is effective for global monitoring. The TOMS data from Nimbus-7 is broadly used, especially for the Antarctic ozone hole monitoring and the temporal trend of ozone density variation. One field of TOMS data usage is the study of the stratosphere-troposphere exchange mechanism. Usually the exchange is said to be caused through the tropopause folding in the mid-latitude associated with the polar and subtropical jet streams. TOMS data shows the good coincidence with the jet stream behaviour[1].
Correction for Nonlinear Photon Counting Effects in Lidar Systems
Authors: Donovan D.P. , Whiteway J.A. , Carswell A.I.
Published: February 2023

Photomultiplier tubes (PMTs) employed in the photon counting (PC) mode of operation are widely used as detectors in lidar systems. Their use, however is restricted mainly to conditions where the signal levels are relatively low and the responses of the PMT and the pulse discrimination/counting system are linear. It is well known that in this low light level regime, where the signal-to-noise (S/N) levels approach unity, the inherent S/N for photon counting is better than that obtained from other detection techniques. A problem encountered with such systems however is the rapid degradation of performance as the signal levels increase. In such situations the photon counting response becomes non-linear and the output count value is no longer proportional to the incident light intensity. In our laboratory we have developed a versatile Nd:YAG lidar which is used for measurements of both the middle atmosphere and the troposphere. [1] With this system we encounter a very wide range of signal levels ranging from the extremely weak signals from the top of the mesosphere to the very strong returns from low level clouds.
Laser Diode Characterization for Optical Remote Sensing Applications
Authors: Chyba Thomas H. , Wang L.-G. , Sachse G. , Mayo L. , Heuser Alene W.
Published: February 2023

Laser diodes are being utilized with increasing frequency in optical remote sensing applications. Their attractive features include small size, low cost, low power consumption, good output power, high modulation speed, good reliability, and good wavelength tunability. However, their optical properties vary significantly even during the same manufacturing run. Therefore, when the application places stringent requirements on their optical properties, diodes need to be individually characterized and evaluated. This paper discusses our present efforts to characterize laser diodes for use in a Differential Absorption Lidar (DIAL) instrument which imposes very tight requirements on diode behavior.
Charge-Coupled-Device Detection for a Doppler-Rayleigh Lidar
Authors: Friedman Jonathan S. , Robison Mark W. , Tepley Craig A. , Castleberg Paul , Garcia Francisco
Published: February 2023

The use of a charge-coupled device (CCD) camera together with a Fabry-Perot etalon (FP) to measure neutral winds in the thermosphere using 630 nm airglow has been proposed by Hays [1990]. In principle, the same technique is used for lidar winds with the sole difference being that a lidar provides its own light source, whereas airglow relies on a naturally occurring emission in the atmosphere. Hays [1990] showed that a CCD array detector attached to an etalon has more than an order of magnitude higher sensitivity than a photomultiplier tube (PMT). Particular advantages of using a CCD are: (1) It can record the whole fringe pattern at once, thus retaining the photons from multiple rings. (2) Because the FP etalon is not scanned, drifting of the location of the fringe pattern is eliminated. (3) The CCD has higher sensitivity to red light than a PMT. This paper is a report on the usefulness of a CCD array to record the fringes from a Doppler-Rayleigh lidar Fabry-Perot etalon for measuring winds and to compare the obtained results with those obtained using a scanning etalon and a PMT.
The Automated Rotating Shadowband Spectroradiometer
Authors: Harrison Lee , Beik Mostafa A. , Michalsky Joseph J.
Published: February 2023

We are developing a photodiode array rotating shadowband spectroradiometer (RSS) as part of the Instrument Development Program (IDP) of the Atmospheric Radiation Measurement (ARM) Program of the United States Department of Energy (DOE). This instrument uses the automated rotating shadowband technique to separate and measure the spectrally resolved direct-normal, total horizontal, and diffuse horizontal irradiances in the 360 to 1060 nm wavelength region. It is intended as an instrument for the central facility of each of the cloud and radiation testbed (CART) sites, and will complement the array of multi-filter rotating shadowband radiometers (MFRSR) currently being deployed by ARM and other research programs including TOGA/COARE.
DIAL in the 3.1 – 3.7m Spectral Region Using Two Simultaneously Pumped Optical Parametric Oscillators.
Authors: Taylor Scott
Published: February 2023

A mobile differential absorption coaxial LIDAR system has been constructed (Petrolaser/LaSen and Titan/Spectron general and subcontractors, respectively) operating in the 3.1 - 3.7 micron range. This instrument is the first of its kind; although, the use of lithium niobate optical parametric oscillators (OPOs) in LIDAR instruments is not new1-3, there have been none that have successfully probed the atmosphere in this spectral region on a consistent basis. The C-H stretching frequency is found in this spectral region thus making this eye safe LIDAR system of intense interest to the petroleum industry for which it was constructed. The primary goals of this device are exploration and environmental monitoring of methane, ethane, and propane.
Results from the flight of the Atmospheric Trace Molecule Spectroscopy on the ATLAS-1 Space Shuttle Mission
Authors: Gunson M. R. , Abrams M. C. , Farmer C. B. , Lowes L. L. , Rinsland C. P. , Zander R.
Published: February 2023

During the ATLAS-1 space shuttle mission, the ATMOS experiment, a Fourier transform infrared spectrometer operating in solar occultation mode from on-orbit (Farmer, 1987), collected data through more than 90 orbital sunrises and sunsets at latitudes between 30°N and 55°S. The resulting high-resolution infrared solar absorption spectra from these observations have so far been analyzed for the vertical profiles of several species (O3, HNO3, ClNO3, HCl, HF, N2O, CH4 and H2O) of immediate importance as correlative measurements for other satellite instruments, such as those carried on the Upper Atmospheric Research Satellite. Results for these gases together with those of other species measured by ATMOS, such as the more abundant man-made chlorofluorocarbons (CFC-11, CFC-12, HCFC-22) are compared with similar measurements made by this instrument from data acquired during its first flight in April, 1985. In the period between these two flights, the halogenated gases are expected to have increased measurably in concentration due to the continued release of the halogenated source gases. These ATMOS data provide a simultaneous measurement of the increase in the tropospheric source gases as well as the halogen sink species, HCl and HF.
Temporal scales of water vapor measured with a Raman lidar during SPECTRE
Authors: Melfi S. Harvey
Published: February 2023

Summary not available at press time.
Coincident Measurements of Atmospheric Aerosol Properties and Water Vapor by a Scanning Raman Lidar
Authors: Ferrare R. A. , Melfi S.H. , Whiteman D. N. , Evans K.D.
Published: February 2023

Knowledge of the physical and optical properties of atmospheric aerosols is required to determine the impact aerosols will have on radiative transfer, heterogeneous chemistry, and cloud dynamics. Since the composition and size of atmospheric aerosols are functions of the atmospheric water vapor, aerosols must be studied in their natural state in order to fully understand how they are affected by various meteorological conditions and how they in turn will affect the processes listed above. By measuring high resolution profiles of aerosol extinction and backscattering as well as simultaneous profiles of atmospheric water vapor, Raman lidar can provide information regarding aerosol microphysical characteristics [Ansmann, et al., 1992; Ferrare et al.,1992]. In addition, the aerosol extinction/backscatter ratio measured directly by Raman lidar can be used in the estimation of aerosol extinction and optical thickness in the inversion procedures used by simpler backscatter lidars. In this presentation, we discuss measurements of aerosol extinction, backscattering, extinction/backscatter ratio, water vapor mixing ratio, and relative humidity made by a scanning Raman lidar over Wallops Island, Virginia (37.95 N, 75.47 W) during August, 1992.
Evaluation of Raman Lidar Profiling of Atmospheric Water Vapor: Simultaneous Measurements with Two Advanced Systems
Authors: Goldsmith J. E. M. , Bisson Scott E. , Whiteman David N. , Melfi S. H. , Ferrare Richard A. , Evans Keith D.
Published: February 2023

The Raman lidar technique has proven to be a powerful method for profiling atmospheric water vapor, one of the most important variables that characterizes the atmosphere. Detailed evaluation of the performance of Raman lidar systems (or lidar systems in general) is complicated by the lack of an appropriate instrument that can provide accurate measurements for intercomparison purposes. In this paper, we describe a detailed intercomparison program performed using two advanced Raman lidar systems. The paper treats in detail only a nighttime intercomparison of water vapor profiles, but the intercomparison program itself will feature daytime and nighttime measurements of both water vapor and aerosol scattering ratios.
SAGE II Water Vapor Profiling; An Inversion Study
Authors: Larsen J.C. , Chu W.P. , Tiwari S.N.
Published: February 2023

The utility of the onion peel method to invert remotely sensed occultation data is well proven for satellite and balloon borne instruments at a variety of spectral resolutions. The advantages of the onion peel technique include stability in the presence of noise, insensitivity to first guess values, computational speed and relatively simple software coding. A major concern with the onion peel inversion method is the potential for the downward propagation of error into successively lower tangent levels that can be accentuated at the highest tangent levels by low signal to noise ratios. A number of inversion techniques have been formulated, tested and successfully applied to atmospheric data that are less susceptible to error propagation. In the Mill and Drayson(1977) method the inversion starts at the lowest tangent level where the highest signals are typically found and proceeds upwards. The profile at and above the tangent level is adjusted with a constant factor derived from the difference between the measured and calculated signal. Measurement errors are dispersed over the full slant path rather than just the tangent level as is the case for the standard onion peel. The method of Carlotti(1988) takes a global-fit approach to limb inversion. At each update step the profile is fit in a least squares sense to the set of limb measurements. Both techniques appear to offer an improvement over the standard onion peel method.
Recent Results in Combined Ground-based and Satellite Remote Sensing
Authors: Westwater E. R. , Stankov B. B.
Published: February 2023

The implementation of the Wind Profiler Demonstration Network [1] is an indication of the increased reliance of the operational community on remote sensors. The Wind Profilers themselves can measure winds to about 16 km with a spatial resolution of 300-900 m on an hourly basis; their horizontal spacings vary from about 200 to 300 km. If the same spatial and temporal coverage of temperature, water vapor and clouds could be achieved many of the needs of forecasters and researchers could be met. However, even if the ambitious goal of measuring both dynamic and thermodynamic variables from a network of surface-based stations could be met, station deployment on a 25 to 50 km grid would be prohibitively expensive. Observations from both polar-orbiting and geostationary satellites, when combined with data from a limited grid of surface-based remote sensors, may provide the necessary horizontal coverage as well as improve upper altitude accuracy. In this paper, we present new results and discuss several possibilities of combining surface-based and satellite data.
Removal of the 3.7 μm Solar Contamination in AVHRR Data
Authors: Rao N.X. , Ou S.C. , Liou K.N.
Published: February 2023

We have developed a numerical scheme for the removal of the solar contamination in the AVHRR 3.7 μm (Ch.3) radiance for the retrieval of cirrus cloud parameters during daytime. The scheme involves an iterative procedure coupled with the clear sky detection technique described by Saunder and Kriebel (1988) and the nighttime retrieval algorithm developed by Ou et al. (1992). In section 2, the removal scheme, based on the correlation between 0.63 and 3.7 μm solar reflectances, is presented. In section 3, we discuss a synthetic study using the midlatitude atmospheric profile and a sensitivity study involving the removal of the 3.7 μm solar component by adding random errors due to surface inhomogeneity and instrument noises. Application of the removal scheme to AVHRR data for inferring cirrus cloud parameters, and comparisons with available observations and retrieval results presented by other investigators are described in section 4. Finally, conclusions are given in section 5.
Remote Sensing of Cirrus Cloud Parameters Using AVHRR 3.7 and 10.9 μm Channel Data
Authors: Ou S.C. , Liou K.N. , Gooch W. , Rao N. , Takano Y.
Published: February 2023

Cirrus clouds are global in nature and occupy primarily the upper troposphere and lower stratosphere. Information on cirrus cloud parameters is critically important to the development of cirrus cloud forecast models, the upgrading of real-time global cloud analysis, and the investigation of cloud-radiation feedback to the temperature perturbations in global climate change.
Initial Data from a New High Spectral Resolution Lidar
Authors: Eloranta E.W. , Piironen P.K.
Published: February 2023

The University of Wisconsin High Spectral Resolution Lidar (HSRL) has been recently redesigned for operation in an electronics semi-trailer van (ref 1). The HSRL can now be deployed in support of field experiments. This paper presents initial observations with the new configuration along with an analysis of measurement accuracy.
Boundary Layer Height Measurements with an Eyesafe Lidar System
Authors: Patterson E. M. , Gimmestad G. G. , Roberts D. W. , Gimmestad S. C.
Published: February 2023

Air chemistry studies require measurements of the depth of the mixed layer in which many of the chemical reactions take place. Lidar measurements provide an attractive option for providing high temporal resolution mixed layer depths in support of these studies. We have developed an eyesafe lidar system for measurements of the vertical distribution of boundary layer aerosols in support of an intensive series of air chemistry measurements conducted as part of the Southern Oxidents Research Program in Atlanta, Ga, during the summer of 1992. This lidar system was used in a semi-automated mode to monitor diurnal variations in vertical distributions of aerosols from which the depths of the boundary layer were inferred.
A Technique for Measuring Winds in the Lower Atmosphere Using Incoherent Doppler Lidar
Authors: DeSlover Daniel. H. , Slaughter Dennis R. , Tulloch William M. , White William E.
Published: February 2023

Wind speed is useful from a meteorological standpoint, in atmospheric modeling, and assessment of trace gas dispersal. A continuing effort is involved in improving the sensitivity of such measurements, and is exemplified by the literature.[1-10] The Mobile Atmospheric Research Laboratory (MARL) at Lawrence Livermore National Laboratory (LLNL) is currently developing a method to improve the sensitivity of wind sounding in the lower through middle atmosphere using a pair of Fabry-Perot interferometers in parallel. This technique, first described by Chanin, et al.[4], for the middle atmosphere using Doppler Rayleigh lidar, can be applied to the lower atmosphere where Mie (aerosol) backscatter is strong. Elastic events, inherent in both Rayleigh and Mie backscatter, dominate the return signal throughout the atmosphere. Both are susceptible to local wind vectors; which will Doppler shift the laser frequency proportional to the wind velocity. A pair of Fabry-Perot interferometers, tuned to either side of the laser frequency, will provide necessary data to determine the shift in frequency of the backscattered signal. Spectral drift and jitter of the laser and a lack of data points to determine the wind vector place limits on the sensitivity of the system. A method to minimize each of these will be presented.
Measurements of Pinatubo Aerosols at Southern Midlatitudes
Authors: Gross M.R. , McGee T.J. , Singh U.N. , McKenzie R.L. , Rosen J.M.
Published: February 2023

NASA Goddard's Stratospheric Ozone Lidar Trailer Experiment (STROZ-LITE) was designed to utilize the DIAL (Differential Absorption Lidar) technique in measuring atmospheric ozone. After the 1991 eruption of Mt. Pinatubo, it became impossible to make accurate measurements of ozone in the region most contaminated by volcanic aerosols (10-30km). The system formally collected light returns at only the emitted laser wavelengths (308 and 351nm). It has since been modified so that the respective signals at 332 and 382nm produced by Raman scattering from nitrogen molecules could also be acquired. This was done so that ozone could be calculated in the aerosol affected region of the atmosphere. Using the same DIAL scheme, but now with the Raman channels at 332nm and 382nm as the on and off-line wavelengths, an accurate ozone measurement can be made between 10 and 30km (McGee et. al, 1992). In making these modifications, a measure of atmospheric aerosol backscatter can be obtained quite simply. With careful normalization, the ratio of 351 to 382nm return signal can directly give the 351nm aerosol scattering ratio (ASR), defined as the Rayleigh plus Mie backscatter divided by only Rayleigh backscatter, since the 351nm signal contains components of both aerosol and molecular backscatter while the 382nm signal contains only molecular backscatter from nitrogen. Whiteman et. al. (1992) describes this procedure in greater detail. With available ancillary atmospheric pressure and temperature data, an Aerosol Volume Backscatter Cross Section profile at 351nm can be quickly calculated from ASR profiles since the Rayleigh cross section at 351nm is well known. The STROZ-LITE system is also now able to determine a measure of aerosol extinction from the 382nm channel. Transmission at this wavelength contains a term for the sum of 351nm plus 382nm aerosol extinction, which can be solved for directly. By assuming a reasonable wavelength dependence, aerosol extinction profiles at 351nm can be computed.
To what extent can routine ozone lidar measurements provide a representative data set in view of the restricted operation time due to cloud cover?
Authors: De Backer Hugo , Visser Eric P. , De Muer Dirk , Swart Daan P.J.
Published: February 2023

For a proper understanding of long term trends in atmospheric ozone concentrations, the availability of high quality data sets is of great importance. At present, total ozone column densities are routinely measured by the ground based Dobson, Brewer and M-83/124 filter ozonometer networks, as well as by satellite based instruments such as the Total Ozone Mapping Spectrometer (TOMS). Vertical concentration profiles are obtained by ground based Umkehr methods, balloon borne electrochemical ozone sondes and by satellite based limb path atmospheric extinction measurements, such as the Stratospheric Aerosol and Gas Experiments (SAGE I/II).
Atmospheric Monitoring for Carbon Monoxide
Authors: Seville-Jones Dyan N. , Martinez Ronald J. , Sander Robert K. , Tiee Joe J.
Published: February 2023

A preliminary study of the flow and concentration of CO over urban intersections is discussed. Results from a tunable diode laser monitoring system are presented.
AlGaAs Aerosol Lidar - Theory & Measurements
Authors: Abshire James B. , Rall Jonathan A.R.
Published: February 2023

In 1983, Takeuchi et al. [1] demonstrated a pseudo-noise (PN) lidar using an externally modulated Argon laser. In 1986, Takeuchi et al. [2] reported PN aerosol lidar measurements using a single AlGaAs laser as a transmitter. We recently reported the design and initial measurements [3,4] made with our AlGaAs lidar which uses a Si APD photon counting detector with a histogram-correlate signal processor.
Evolution of Pinatubo and Cerro Hudson Aerosol Over the Antarctic During the 1991 Austral Spring
Authors: Pitts Michael C. , Thomason Larry W. , Chu William P.
Published: February 2023

The eruption of Mt. Pinatubo (15.1°N, 120.4°E) in the Philippines on June 15, 1991, injected large amounts of SO2 into the stratosphere as high as 30 km (McCormick, 1992). The SO2underwent rapid conversion to H2SO4/H2O aerosol, and after the first few weeks following the eruption, the aerosol had dispersed in a band over the tropics between 20°S and 30°N. In subsequent weeks, substantial amounts of aerosol were transported to the mid-latitudes of both hemispheres, and by early September, satellite observations indicated a layer of Pinatubo aerosol centered near 21 km had reached as far south as the outer edge of the Antarctic polar vortex (McCormick and Veiga, 1992). In addition, the Cerro Hudson volcano in southern Chile (45.92°S, 73.0°W) erupted intermittently from August 12-15, 1991, sending significant amounts of SO2 into the lower stratosphere, primarily below 14 km. Satellite observations indicated that the Cerro Hudson cloud initially became embedded in a predominantly westerly flow, and after two weeks was dispersed in a band between 50°S and 65°S (Doiron et al.,1991). Thus, at the onset of the 1991 Austral spring, two distinct volcanic aerosol clouds were present in the stratosphere over the polar regions of the Southern Hemisphere. In this study, we utilize SAM II and SAGE II data to identify and track the movement of these volcanic clouds and study transport processes associated with the Antarctic polar vortex during the spring.
Lidar Measurements of the Stratospheric Aerosol Layer over Toronto
Authors: Donovan D.P. , Steinbrecht W. , Carswell A.I.
Published: February 2023

Since March 1991, lidar measurements of the stratospheric aerosol layer over Toronto Canada (42.80° N, 79.50° W) have been routinely conducted at wavelengths of 353nm and 532nm .
Lidar Observations of Mt. Pinatubo Aerosols: Effects on the Global Radiation Budget
Authors: Stevens T. D. , Maruvada S. , Kane T. J. , Philbrick C. R.
Published: February 2023

Significant amounts of stratospheric aerosols can cause a cooling of the earth's surface due to the scattering of solar radiation back into space. Likewise a warming of the stratosphere where the particles reside will occur due to absorption of upwelling infrared radiation [1]. The eruption of the Pinatubo volcano in the Philippines (15.14°N, 120.35°E) on June 15, 1991, produced the largest impact on the stratosphere ever observed by modem airborne, spaceborne, and ground-based scientific instruments. The volcanic aerosols were ejected into the upper troposphere and the stratosphere to heights above 33 km. Due to their long residence time, the volcanic aerosols were transported around the globe in about three weeks [2]. The effects are spread in the meridional direction by the interactions of large scale planetary waves with the resivour regions about the equator. By September 27 small amounts were observed as far north as Norway.
Derivation of CLAES Filter Shapes
Authors: Mergenthaler J.L. , Potter J.F. , Kumer J.B. , James T.C. , Roche A.E.
Published: February 2023

The Cryogenic Limb Array Etalon Spectrometer, CLAES, was launched on September 12, 1991 aboard the NASA Upper Atmosphere Research Satellite (UARS) and has been acquiring data on stratospheric composition since October 1, 1991. Overviews of the CLAES experiment and hardware are given by Roche et al (1) and Burriesci et al. (2). In the OSA Topical Meeting on Optical Remote Sensing of the Atmosphere in 1990 we presented three papers, (3,4,5) that described our progress up to that time in defining the system spectral transmission. In this paper, we describe refinements to CLAES characterization since then. These have come from further work with the pre-launch cold test data and from on-flight data. The spectral transmission characterization described here is currently being used in CLAES retrieval software. Figure (1) shows a schematic diagram of the spectrometer. In normal operation the CLAES instrument achieves a 0.2-0.65 cm-1 spectral resolution by passing the radiation through one of nine passband blocking filters (FWHM ~10 cm-1) mounted in a filter wheel, and one of four Fabry-Perot etalons which are mounted in a paddle wheel to provide for spectral scanning by tilting. The transmitted radiation then falls on a focal plane array consisting of a main array of 20 elements and an HCI array of 3 elements. The main detector array is used by eight spectral channels from 5.3 to 12.8 μm and takes atmospheric data in 20-2.5 km vertical increments. The 3-element HCL array is used only by the 3.5 μm channel where each detector spans approximately 16 km for S/N augmentation.
A Novel Collector for High Altitude Aircraft Observations of Solar Ultraviolet Flux
Authors: Burris J.
Published: February 2023

An inexpensive technique to quickly and reliably collect the integrated solar flux over a hemisphere is described.
From 'Onion Peeling' to 'Cutting Onion Cubes'
Authors: Clarmann Thomas v.
Published: February 2023

Long horizontal paths and rapid changes of observer position combined with large horizontal gradients in mixing ratios of trace gases of interest are the reason for the need of a two-dimensional approach for analysis of limb emission spectra from space-borne experiments. A data evaluation concept is de-scribed and discussed which is based on classical one-dimensional 'onion peeling' approach, but avoids the assumption of spherical homogeneity.
Determination of Ejection Power of Pollutants According To Optical Radiation Backscattering
Authors: Banakh V.A. , Smalikho I.N.
Published: February 2023

The paper presents a method for remote determination of ejection power of a local source of pollution from the measurements of backscattering intensity when sounding the smoke plumes using a directed cw optical beam. For the light intensity distribution along the coordinate x in the image plane of smoke plume we can write the following formula /1/
Stratospheric aerosol measuring from Obninsk lidar station following the volcano Pinatubo eruption
Authors: Khmelevtsov S.S. , Kaufman Yu.G.
Published: February 2023

The eruption effect on stratospheric aerosol was first observed during lidar sounding at Obninsk station (55°N, 37°E ) in 37 days following the eruption, 22 of July , 1991. The devices used for sounding are described in [1]. The speed of cloud movement, computed on the given measurements, has been found to be more than 1 degree per twenty four hours. 21 of February, 1992 the integral backscatter reached the value 3,67 10−3 Br−1 ( the measurements were carried out at the wavelength of 532 nm ) in the layer of 15-30 km and than began to decrease. According to preliminary results the time of relaxation of the stratospheric aerosol in latitude 55°North is close to 10 months, i.e. just less than the relaxation time of the stratospheric aerosol formed following volcano El Chichon in 1982.
Continuous Measurement of Boundary Layer Temperature and Moisture Structure Using Ground-Based FTIR
Authors: Smith W. L. , Knuteson R. O. , Revercomb H. E. , Howell H. B.
Published: February 2023

During the past decade a number of remote sensing devices to provide continuous atmospheric profile observations from the ground have been examined (Dabbert 1990). Several of these, including the doppler radar wind "Profiler" and the Radar Acoustic temperature Sounding System (RASS), are close to routine operational implementation. A RAMAN Lidar, developed for water vapor profiling, has proven to be an excellent research tool with some hope for operational implementation when the cost and complexity of the technology is reduced during the coming years.
Polar Ozone and Aerosol Measurement Experiment (POAM-II)
Authors: Lehmann F. J. , Bevilacqua R. M. , Glaccum W. J. , Hornstein J. S. , Krigman S. S. , Lumpe J. D. , Shettle E. P.
Published: February 2023

NRL will launch POAM II in September 1993, to measure polar stratospheric 03, H2O, NO2, and aerosol extinction. The satellite system description is presented.
Diode Laser-based Sensor System for Long-Path Absorption Measurements of Atmospheric Concentration and Near-IR Molecular Spectral Parameters.
Authors: Goldstein Neil , Lee Jamine , Adler-Golden Steven M. , Bien Fritz
Published: February 2023

Line-locked near-IR diode lasers and a simple retroreflector/telescope system were used for remote sensing of atmospheric constituents over long atmospheric paths. Figure 1 shows the experimental configuration used in preliminary measurements of atmospheric water vapor and oxygen with AlGaAs diode lasers. A prototype field sensor system currently under development shares the same basic configuration but incorporates interchangeable AlGaAs and InGaAsP diode-laser modules for monitoring a variety of atmospheric gases.
Lidar and Radiometer Observations of Midlevel Clouds
Authors: Platt C.M.R. , Young S.A. , Patterson G.R. , Manson P.J.
Published: February 2023

Midlevel clouds occur in the region of the troposphere, lying between high cirrus ice clouds and low boundary layer stratus, stratocumulus and cumulus clouds. Midlevel clouds are associated with moisture advected to the middle part of the troposphere between about 2km and 6km, or temperatures between about 0°C and -20°C. However, there is no sharp gradation between cirrus and altus clouds, rather, a blending of one into the other. Again, deep frontal clouds, which include midlevel cloud, can extend from cirrus level to the boundary layer. Both the depths and the compositions of midlevel clouds are thus very variable. The clouds can often exist as supercooled water drops, which sometimes glaciate rapidly; as the saturation vapour pressure over ice is lower than over water, and the deficit is maximum at about -15°C in the mid-troposphere, any tendency for ice crystals to form can cause rapid growth of the crystals at the expense of the water drops. Optical remote sensing of these clouds has been confined in the past to a few observations (e.g. Platt and Gambling, 1971, Platt and Bartusek, 1974, Platt, 1977, Sassen, 1984, Uchino et al., 1988). However, recently, a few more observations were made in the first FIRE experiment (e.g. Heymsfield et al., 1991) although observations tended to concentrate on cirrus.
Lidar Cloud Observaion: In Part of Eclips Phase II in the Region of Sofia
Authors: Kolev I. , Parvanov O. , Kaprielov B. , Tomova Y.
Published: February 2023

The ECLIPS project in which our lidar group also takes part is well described [1]. In general, the main purpose is a ground-based lidar observation of the clouds simultaneously with the NOAA 10 and NOAA 11 meteorological satellites overpassing the same areas to be performed. Essential data are the recorded profiles of the lidar returns from which certain information about the clouds height, optical depth and vertical extinction can be derived.
Tropospheric Temperature Measurements Using a Raman Lidar
Authors: Evans K. D. , Melfi S. H. , Ferrare R. A. , Whiteman D. N.
Published: February 2023

The GSFC Raman lidar measures temperature in the troposphere as well as water vapor and aerosols (Whiteman et al. 1992a). Strauch et al. (1971) demonstrated that atmospheric temperature can be determined using the Raman backscatter from nitrogen and Hauchecorne et al. (1992) used the Raman vibrational scattering from nitrogen to calculate temperature in the lower stratosphere. In this paper, we present density and temperature profiles in the troposphere using the Raman vibrational scattering from nitrogen.
A.E.S. DIAL System for Monitoring of Tropospheric Ozone.
Authors: Hahn J. F. , Sheppard A. , Hoff R. M.
Published: February 2023

In order to better understand the mechanisms controlling atmospheric ozone transfer and production in the troposphere, as well as ozone exchange between the troposphere and stratosphere, the Atmospheric Environment Service has undertaken to build a differential absorption lidar (DIAL) system at its Centre for Atmospheric Research Experiments facility in Egbert, Ontario, located approximately 80 kilometres north of metropolitan Toronto. The system under construction will employ Raman shifting of quadrupled Nd:YAG output at 266 nm to 289.9 and 294.2 nm through the use of HD and D2 respectively (1,2). This is a basic change in approach from the earlier dye laser-based system used by A.E.S. at the Centre for Atmospheric Research Experiments (C.A.R.E.) (3).
Laser Long-Path Absorption Measurements with the Retroreflector in Space for the ADEOS Satellite
Authors: Sugimoto N. , Minato A. , Sasano Y. , Itabe T. , Hiromoto N. , Takabe M.
Published: February 2023

Experiments on earth-satellite-earth laser long-path absorption measurement of atmospheric trace species will be performed with the Retroreflector In Space (RIS) which is to be loaded on the Advanced Earth Observing Satellite (ADEOS). The ADEOS is a Japanese polar-orbit satellite which is scheduled for launch in early 1996. RIS is a single-element cube-corner retroreflector with an effective diameter of 0.5 m. In the RIS experiments, a laser beam is transmitted from a ground station, reflected by RIS, and received at the ground station. The absorption of atmospheric trace species is measured in the round-trip optical path.
Probing the Martian Atmosphere in the Ultraviolet
Authors: Lindner Bernhard Lee
Published: February 2023

Several fundamental differences in atmospheric chemistry exist between Mars and the Earth. The martian atmosphere is primarily CO2 (95%), with strong vertical mixing, cold temperatures (typically 220K), low pressures (6 mb at the surface), high atmospheric dust and cloud particle content, and no man-made atmospheric constituents. Earlier difficulties in explaining why the atmosphere was not more decomposed into CO and O2 have been placated with models using updated reaction rates, 'moderate' eddy mixing of order 107 cm2s-1, and the odd hydrogen catalytic cycle (Shimazaki, 1989; Krasnopolsky, 1992). Odd nitrogen and sulfur catalytic cycles are of marginal importance, and other catalytic cycles shown to be important in the terrestrial atmosphere are unimportant on Mars (Yung et al., 1977; Krasnopolsky, 1992). Currently, much work is being undertaken to examine the importance of heterogeneous chemistry (e.g., Atreya and Blamont, 1990; Krasnopolsky, 1992), but uncertainties in particle properties make efficiencies difficult to evaluate. Also, atmospheric chemistry may significantly alter atmospheric composition on climatic timescales, particularly during periods of low obliquity (Lindner and Jakosky, 1985).
RIVMs tropospheric and stratospheric ozone lidars for European and Global monitoring networks
Authors: Swart Daan P.J. , Apituley Arnoud , Spakman Jan , Visser Eric P. , Bergwerff Hans B.
Published: February 2023

Background tropospheric ozone levels have doubled since 1900 [1], and are presently increasing at a rate of 1 % per year[2]. Of all trace gases in the lower atmosphere, ozone has reached concentration levels closest to proven toxic levels on man[3]. Crop yield in the Netherlands is estimated to be lower by 3 to 4% (300-400 million US $) due to higher ozone levels during the growth season[4]. Column (i.e. mainly stratospheric) ozone levels at northern hemisphere mid latitudes have gone down by 5 to 6% between 1970 and 1991 [5]. The expected increased exposure of the earth surface to UV-B has many adverse effects on man and environment[6]. The changing vertical distribution of ozone may be reflected in climate changes as well[5].
NDSC and Lidar Observations at OHP
Authors: Godin Sophie
Published: February 2023

Summary not available at press time.
Examples of GOES-8 Data and Products
Authors: Menzel W. Paul , Purdom James F. W.
Published: February 2023

On 13 April 1994, the first of NOAA's next generation of geostationary satellites, GOES-8, was launched. All components of the GOES-8 system are new or greatly improved: (1) the satellite is earth oriented to improve instrument performance; (2) sounding and imaging operations are now performed by different and separate instruments; (3) a five band multispectral radiometer with higher spatial resolution improves imaging capabilities; (4) a sounder with higher radiometric sensitivity enables operational temperature and moisture profile retrieval from geostationary altitude for the first time; (5) a different data format is used to retransmit raw data to direct receive users; and, (6) a new ground data processing system handles the high data volume and distributes advanced products to a variety of users.
Effects of the Inhomogeneity of the Atmosphere on the Multiple Scattering in Lidar Sounding from Space
Authors: Flesia Cristina , Starkov Andrei V.
Published: February 2023

We used variance reduction Monte Carlo method [1] and analytical extension of the Mie theory [2] to calculate spaceborn lidar returns from the pure and cloudy atmosphere and we analysed the influence of multiple scattering on the interpretation of measurements. In particular, the performance capabilities of identification of cloud layers from space has been evaluated.
Aerosol and Cloud Observations from the Lidar In-space Technology Experiment
Authors: Winker D. M.
Published: February 2023

The Lidar In-Space Technology Experiment (LITE) is a backscatter lidar built by NASA Langley Research Center to fly on the Space Shuttle. The purpose of the program was to develop the engineering processes required for space lidar and to demonstrate applications of space lidar to remote sensing of the atmosphere. The instrument was flown on Discovery in September 1994. Global observations of clouds and aerosols were made between the latitudes of 57°N and 57°S during 10 days of the mission.
Imaging Spectrometer Measurement of Water Vapor in the 400 to 2500 nm Spectral Region
Authors: Green Robert O. , Roberts Dar A. , Conel James E. , Dozier Jeff
Published: February 2023

The Airborne Visible-Infrared Imaging Spectrometer (AVIRIS) measures the total upwelling spectral radiance from 400 to 2500 nm sampled at 10 nm intervals. The instrument acquires spectral data at an altitude of 20 km above sea level, as images of 11 by up to 100 km at 17x17 meter spatial sampling. We have developed a nonlinear spectral fitting algorithm coupled with a radiative transfer code to derive the total path water vapor from the spectrum, measured for each spatial element in an AVIRIS image. The algorithm compensates for variation in the surface spectral reflectance and atmospheric aerosols. It uses water vapor absorption bands centered at 940 nm 1040 nm, and 1380 nm.