31 results match your criteria Atmospheric Measurement Techniques[Journal]

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Cloud Products from the Earth Polychromatic Imaging Camera (EPIC): Algorithms and Initial Evaluation.

Atmos Meas Tech 2019 29;12(3):2019-2031. Epub 2019 Mar 29.

NASA Langley Research Center, Hampton, VA.

This paper presents the physical basis of the EPIC cloud product algorithms and an initial evaluation of their performance. Since June 2015, EPIC has been providing observations of the sunlit side of the Earth with its 10 spectral channels ranging from the UV to the near-IR. A suite of algorithms has been developed to generate the standard EPIC Level 2 Cloud Products that include cloud mask, cloud effective pressure/height, and cloud optical thickness. Read More

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http://dx.doi.org/10.5194/amt-12-2019-2019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6951331PMC

Using a Speed-Dependent Voigt Line Shape to Retrieve O from Total Carbon Column Observing Network Solar Spectra to Improve Measurements of XCO.

Atmos Meas Tech 2019 ;12

Harvard John A. Paulson School of Engineering and Applied Sciences, Cambridge, MA, USA.

High-resolution, laboratory, absorption spectra of the oxygen (O) band measured using cavity ring-down spectroscopy were fitted using the Voigt and speed-dependent Voigt line shapes. We found that the speed-dependent Voigt line shape was better able to model the measured absorption coefficients than the Voigt line shape. We used these line shape models to calculate absorption coefficients to retrieve atmospheric total columns abundances of O from ground-based spectra from four Fourier transform spectrometers that are apart of the Total Carbon Column Observing Network (TCCON) Lower O total columns were retrieved with the speed-dependent Voigt line shape, and the difference between the total columns retrieved using the Voigt and speed-dependent Voigt line shapes increased as a function of solar zenith angle. Read More

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http://dx.doi.org/10.5194/amt-12-35-2019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6774361PMC
January 2019
1 Read

Characterising low-cost sensors in highly portable platforms to quantify personal exposure in diverse environments.

Atmos Meas Tech 2019 30;12(8):4643-4657. Epub 2019 Aug 30.

Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK.

The inaccurate quantification of personal exposure to air pollution introduces error and bias in health estimations, severely limiting causal inference in epidemiological research worldwide. Rapid advancements in affordable, miniaturised air pollution sensor technologies offer the potential to address this limitation by capturing the high variability of personal exposure during daily life in large-scale studies with unprecedented spatial and temporal resolution. However, concerns remain regarding the suitability of novel sensing technologies for scientific and policy purposes. Read More

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http://dx.doi.org/10.5194/amt-12-1-2019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6751078PMC
August 2019
2 Reads

Using collision-induced dissociation to constrain sensitivity of ammonia chemical ionization mass spectrometry ( CIMS) to oxygenated volatile organic compounds.

Atmos Meas Tech 2019 20;12(3):1861-1870. Epub 2019 Mar 20.

John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA.

Chemical ionization mass spectrometry (CIMS) instruments routinely detect hundreds of oxidized organic compounds in the atmosphere. A major limitation of these instruments is the uncertainty in their sensitivity to many of the detected ions. We describe the development of a new high-resolution time-of-flight chemical ionization mass spectrometer that operates in one of two ionization modes: using either ammonium ion ligand-switching reactions such as for CIMS or proton transfer reactions such as for protontransfer-reaction mass spectrometer (PTR-MS). Read More

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http://dx.doi.org/10.5194/amt-12-1861-2019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7094031PMC

Assessing snow extent data sets over North America to inform and improve trace gas retrievals from solar backscatter.

Atmos Meas Tech 2018 22;11(5):2983-2994. Epub 2018 May 22.

Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada.

Accurate representation of surface reflectivity is essential to tropospheric trace gas retrievals from solar backscatter observations. Surface snow cover presents a significant challenge due to its variability and thus snow-covered scenes are often omitted from retrieval data sets; however, the high reflectance of snow is potentially advantageous for trace gas retrievals. We first examine the implications of surface snow on retrievals from the upcoming TEMPO geostationary instrument for North America. Read More

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http://dx.doi.org/10.5194/amt-11-2983-2018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6235450PMC
May 2018
6 Reads

Chromatography related performance of the Monitor for AeRosols and GAses in ambient air (MARGA): laboratory and field-based evaluation.

Atmos Meas Tech 2017 Oct;10(10):3893-3908

National Risk Management Research Laboratory, Office of Research and Development, US Environmental Protection Agency, Research Triangle Park, North Carolina, 27711, USA.

Evaluation of the semi-continuous Monitor for AeRosols and GAses in ambient air (MARGA, Metrohm Ap-plikon B.V.) was conducted with an emphasis on examination of accuracy and precision associated with processing of chromatograms. Read More

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http://dx.doi.org/10.5194/amt-10-3893-2017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6192433PMC
October 2017
5 Reads

CALIPSO IIR Version 2 Level 1b calibrated radiances: analysis and reduction of residual biases in the Northern Hemisphere.

Atmos Meas Tech 2018 Apr;11(4):2485-2500

Laboratoire de Météorologie Dynamique, Ecole Polytechnique-CNRS, Palaiseau, 91128, France.

Version 2 of the Level 1b calibrated radiances of the Imaging Infrared Radiometer (IIR) on board the Cloud-Aerosol Lidar and Infrared Satellite Observation (CALIPSO) satellite has been released recently. This new version incorporates corrections of small but systematic seasonal calibration biases previously revealed in Version 1 data products mostly north of 30° N. These biases of different amplitudes in the three IIR channels 8. Read More

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http://dx.doi.org/10.5194/amt-11-2485-2018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6907013PMC

A Prototype Method for Diagnosing High Ice Water Content Probability Using Satellite Imager Data.

Atmos Meas Tech 2018 Mar;11(3):1615-1637

Laboratoire Atmosphere, Milieux, et Observations Spatiales, Guyancourt, France.

Recent studies have found that flight through deep convective storms and ingestion of high mass concentrations of ice crystals, also known as high ice water content (HIWC), into aircraft engines can adversely impact aircraft engine performance. These aircraft engine icing events caused by HIWC have been documented during flight in weak reflectivity regions near convective updraft regions that do not appear threatening in onboard weather radar data. Three airborne field campaigns were conducted in 2014 and 2015 to better understand how HIWC is distributed in deep convection, both as a function of altitude and proximity to convective updraft regions, and to facilitate development of new methods for detecting HIWC conditions, in addition to many other research and regulatory goals. Read More

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http://dx.doi.org/10.5194/amt-11-1615-2018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6750020PMC

A Cloud-Ozone Data Product from Aura OMI and MLS Satellite Measurements.

Atmos Meas Tech 2017 1;10(11):4067-4078. Epub 2017 Nov 1.

NASA Goddard Space Flight Center, Greenbelt, Maryland, USA.

Ozone within deep convective clouds is controlled by several factors involving photochemical reactions and transport. Gas-phase photochemical reactions and heterogeneous surface chemical reactions involving ice, water particles, and aerosols inside the clouds all contribute to the distribution and net production and loss of ozone. Ozone in clouds is also dependent on convective transport that carries low troposphere/boundary layer ozone and ozone precursors upward into the clouds. Read More

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http://dx.doi.org/10.5194/amt-10-4067-2017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5810404PMC
November 2017
32 Reads

The CALIPSO Version 4 Automated Aerosol Classification and Lidar Ratio Selection Algorithm.

Atmos Meas Tech 2018 ;11(11):6107-6135

Science Systems and Applications, Inc., Hampton, VA, USA.

The Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) version 4.10 (V4) level 2 aerosol data products, released in November 2016, include substantial improvements to the aerosol subtyping and lidar ratio selection algorithms. These improvements are described along with resulting changes in aerosol optical depth (AOD). Read More

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http://dx.doi.org/10.5194/amt-11-6107-2018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6951257PMC
January 2018

Long-term evaluation of air sensor technology under ambient conditions in Denver, Colorado.

Atmos Meas Tech 2018 ;11(8):4605-4615

Jacobs Technology, Inc, Research Triangle Park, NC 27709, USA.

Air pollution sensors are quickly proliferating for use in a wide variety of applications, with a low price point that supports use in high-density networks, citizen science, and individual consumer use. This emerging technology motivates the assessment under real-world conditions, including varying pollution levels and environmental conditions. A seven-month, systematic field evaluation of low-cost air pollution sensors was performed in Denver, Colorado, over 2015-2016; the location was chosen to evaluate the sensors in a high-altitude, cool, and dry climate. Read More

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http://dx.doi.org/10.5194/amt-11-4605-2018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6781239PMC
January 2018

On the consistency of HNO and NO in the Aleutian High region from the Nimbus 7 LIMS Version 6 data set.

Atmos Meas Tech 2018 21;11(6):3611-3626. Epub 2018 Jun 21.

Laboratory for Atmospheric and Space Physics Atmospheric and Oceanic Sciences University of Colorado, UCB 311 Boulder, Colorado 80309, USA.

This study uses photochemical calculations along kinematic trajectories in conjunction with Limb Infrared Monitor of the Stratosphere (LIMS) observations to examine the changes in HNO and NO near 30 hPa in the region of the Aleutian High (AH) during the minor warming event of January 1979. An earlier analysis of Version 5 (V5) LIMS data indicated increases in HNO without a corresponding decrease in NO in that region and a quasi-wave 2 signature in the zonal distribution of HNO, unlike the wave 1 signal in ozone and other tracers. Version 6 (V6) LIMS also shows an increase of HNO in that region, but NO is smaller than from V5. Read More

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http://dx.doi.org/10.5194/amt-11-3611-2018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6677156PMC

Intercomparison of Open-Path Trace Gas Measurements with Two Dual Frequency Comb Spectrometers.

Atmos Meas Tech 2017 11;10(9):3295-3311. Epub 2017 Sep 11.

Physical Measurement Laboratory, National Institute of Standards and Technology, 325 Broadway, Boulder, CO 80305.

We present the first quantitative intercomparison between two open-path dual comb spectroscopy (DCS) instruments which were operated across adjacent 2-km open-air paths over a two-week period. We used DCS to measure the atmospheric absorption spectrum in the near infrared from 6021 to 6388 cm (1565 to 1661 nm), corresponding to a 367 cm bandwidth, at 0.0067 cm sample spacing. Read More

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http://dx.doi.org/10.5194/amt-2017-62DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5740489PMC
September 2017
22 Reads

An online monitor of the oxidative capacity of aerosols (o-MOCA).

Atmos Meas Tech 2017 28;10(2):633-644. Epub 2017 Feb 28.

Aerosol Dynamics Inc., 935 Grayson St., Berkeley, CA, USA.

The capacity of airborne particulate matter to generate reactive oxygen species (ROS) has been correlated with the generation of oxidative stress both in vitro and in vivo. The cellular damage from oxidative stress, and by implication with ROS, is associated with several common diseases, such as asthma and chronic obstructive pulmonary disease (COPD), and some neurological diseases. Yet currently available chemical and in vitro assays to determine the oxidative capacity of ambient particles require large samples, analyses are typically done offline, and the results are not immediate. Read More

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http://dx.doi.org/10.5194/amt-10-633-2017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5703220PMC
February 2017
4 Reads

Differences in liquid cloud droplet effective radius and number concentration estimates between MODIS Collections 5.1 and 6 over global oceans.

Atmos Meas Tech 2017 8;10(6):2105-2116. Epub 2017 Jun 8.

NASA Goddard Space Flight Center, Greenbelt, Maryland, 20771, USA.

Differences in cloud droplet effective radius and cloud droplet number concentration (CDNC) estimates inferred from the Aqua MODIS Collections 5.1 and 6 cloud products (MYD06) are examined for warm clouds over global oceans for the year 2008. Individual pixel level retrievals for both collections are aggregated to 1° × 1° and compared globally and regionally for the three main spectral channel pairs used for MODIS cloud optical property retrievals. Read More

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http://dx.doi.org/10.5194/amt-10-2105-2017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5662204PMC
June 2017
2 Reads

Eddy covariance carbonyl sulphide flux measurements with a quantum cascade laser absorption spectrometer.

Atmos Meas Tech 2017 Sep;10(9):3525-3537

Institut of Ecology, University of Innsbruck, Innsbruck, Austria.

The trace gas carbonyl sulphide (COS) has lately received growing interest in the eddy covariance (EC) community due to its potential to serve as an independent approach for constraining gross primary production and canopy stomatal conductance. Thanks to recent developments of fast-response high-precision trace gas analysers (e.g. Read More

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http://dx.doi.org/10.5194/amt-10-3525-2017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5662146PMC
September 2017
3 Reads

Recent divergences in stratospheric water vapor measurements by frost point hygrometers and the Aura Microwave Limb Sounder.

Atmos Meas Tech 2016 Sep;9(9):4447-4457

Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, USA.

Balloon-borne frost point hygrometers (FPs) and the Aura Microwave Limb Sounder (MLS) provide high-quality vertical profile measurements of water vapor in the upper troposphere and lower stratosphere (UTLS). A previous comparison of stratospheric water vapor measurements by FPs and MLS over three sites - Boulder, Colorado (40.0° N); Hilo, Hawaii (19. Read More

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http://dx.doi.org/10.5194/amt-9-4447-2016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5619251PMC
September 2016
12 Reads

Evaluation and environmental correction of ambient CO measurements from a low-cost NDIR sensor.

Atmos Meas Tech 2017 ;10

Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD 20742, USA.

Non-dispersive infrared (NDIR) sensors are a low-cost way to observe carbon dioxide concentrations in air, but their specified accuracy and precision are not sufficient for some scientific applications. An initial evaluation of six SenseAir K30 carbon dioxide NDIR sensors in a lab setting showed that without any calibration or correction, the sensors have an individual root mean square error (RMSE) between ~5 and 21 parts per million (ppm) compared to a research-grade greenhouse gas analyzer using cavity enhanced laser absorption spectroscopy. Through further evaluation, after correcting for environmental variables with coefficients determined through a multivariate linear regression analysis, the calculated difference between the each of six individual K30 NDIR sensors and the higher-precision instrument had an RMSE of between 1. Read More

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https://www.atmos-meas-tech.net/10/2383/2017/
Publisher Site
http://dx.doi.org/10.5194/amt-10-2383-2017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6463532PMC
January 2017
24 Reads

Cross-calibration of S-NPP VIIRS moderate resolution reflective solar bands against MODIS Aqua over dark water scenes.

Atmos Meas Tech 2017 13;10(4):1425-1444. Epub 2017 Apr 13.

Space Science and Engineering Center, University of Wisconsin, Madison, WI, USA.

The Visible Infrared Imaging Radiometer Suite (VIIRS) is being used to continue the record of Earth Science observations and data products produced routinely from National Aeronautics and Space Administration (NASA) Moderate Resolution Imaging Spectroradiometer (MODIS) measurements. However, the absolute calibration of VIIRS's reflected solar bands is thought to be biased, leading to offsets in derived data products such as aerosol optical depth (AOD) as compared to when similar algorithms are applied to different sensors. This study presents a cross-calibration of these VIIRS bands against MODIS Aqua over dark water scenes, finding corrections to the NASA VIIRS Level 1 (version 2) reflectances between approximately +1 % and -7 % (dependent on band) are needed to bring the two into alignment (after accounting for expected differences resulting from different band spectral response functions), and indications of relative trending of up to ^0. Read More

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http://dx.doi.org/10.5194/amt-10-1425-2017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6155460PMC
April 2017
1 Read

Assessment of Mixed-Layer Height Estimation from Single-wavelength Ceilometer Profiles.

Atmos Meas Tech 2017 ;10:3963-3983

NASA Langley Research Center, Hampton, Virginia 23681, USA.

Differing boundary/mixed-layer height measurement methods were assessed in moderately-polluted and clean environments, with a focus on the Vaisala CL51 ceilometer. This intercomparison was performed as part of ongoing measurements at the Chemistry And Physics of the Atmospheric Boundary Layer Experiment (CAPABLE) site in Hampton, Virginia and during the 2014 Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) field campaign that took place in and around Denver, Colorado. We analyzed CL51 data that were collected via two different methods (BLView software, which applied correction factors, and simple terminal emulation logging) to determine the impact of data collection methodology. Read More

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http://dx.doi.org/10.5194/amt-10-3963-2017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5906814PMC
January 2017
18 Reads

In-flight performance of the Ozone Monitoring Instrument.

Atmos Meas Tech 2017 1;10(5):1957-1986. Epub 2017 Jun 1.

Royal Netherlands Meteorological Institute KNMI, De Bilt, The Netherlands.

The Dutch-Finnish Ozone Monitoring Instrument (OMI) is an imaging spectrograph flying on NASA's EOS Aura satellite since July 15, 2004. OMI is primarily used to map trace gas concentrations in the Earth's atmosphere, obtaining mid-resolution (0.4-0. Read More

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http://dx.doi.org/10.5194/amt-2016-420DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5893161PMC
June 2017
4 Reads

The detection of carbon dioxide leaks using quasi-tomographic laser absorption spectroscopy measurements in variable wind.

Atmos Meas Tech 2016 Apr;9:1627-1636

Atmospheric and Environmental Research, 131 Hartwell Avenue, Lexington, Massachusetts, 02421, USA.

Laser absorption spectroscopy (LAS) has been used over the last several decades for the measurement of trace gasses in the atmosphere. For over a decade, LAS measurements from multiple sources and tens of retroreflectors have been combined with sparse-sample tomography methods to estimate the 2-D distribution of trace gas concentrations and underlying fluxes from point-like sources. In this work, we consider the ability of such a system to detect and estimate the position and rate of a single point leak which may arise as a failure mode for carbon dioxide storage. Read More

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http://dx.doi.org/10.5194/amt-9-1627-2016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4955779PMC
April 2016
6 Reads

Ground-based assessment of the bias and long-term stability of fourteen limb and occultation ozone profile data records.

Atmos Meas Tech 2016 8;9(6):2497-2534. Epub 2016 Jun 8.

NASA Langley Research Center, Hampton, VA, USA.

The ozone profile records of a large number of limb and occultation satellite instruments are widely used to address several key questions in ozone research. Further progress in some domains depends on a more detailed understanding of these data sets, especially of their long-term stability and their mutual consistency. To this end, we made a systematic assessment of fourteen limb and occultation sounders that, together, provide more than three decades of global ozone profile measurements. Read More

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http://dx.doi.org/10.5194/amtd-8-6661-2015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5937289PMC
June 2016
1 Read

Investigation of a potential HCHO measurement artifact from ISOPOOH.

Atmos Meas Tech 2016 16;9(9):4561-4568. Epub 2016 Sep 16.

Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA.

Recent laboratory experiments have shown that a first generation isoprene oxidation product, ISOPOOH, can decompose to methyl vinyl ketone (MVK) and methacrolein (MACR) on instrument surfaces, leading to overestimates of MVK and MACR concentrations. Formaldehyde (HCHO) was suggested as a decomposition co-product, raising concern that in situ HCHO measurements may also be affected by an ISOPOOH interference. The HCHO measurement artifact from ISOPOOH for the NASA In Situ Airborne Formaldehyde instrument (ISAF) was investigated for the two major ISOPOOH isomers, (1,2)-ISOPOOH and (4,3)-ISOPOOH, under dry and humid conditions. Read More

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http://dx.doi.org/10.5194/amt-9-4561-2016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5889939PMC
September 2016
8 Reads

Instrumentation and Measurement Strategy for the NOAA SENEX Aircraft Campaign as Part of the Southeast Atmosphere Study 2013.

Atmos Meas Tech 2016 18;9(7):3063-3093. Epub 2016 Jul 18.

Department of Chemistry, Hendrix College, 1600 Washington Ave., Conway, AR, USA.

Natural emissions of ozone-and-aerosol-precursor gases such as isoprene and monoterpenes are high in the southeast of the US. In addition, anthropogenic emissions are significant in the Southeast US and summertime photochemistry is rapid. The NOAA-led SENEX (Southeast Nexus) aircraft campaign was one of the major components of the Southeast Atmosphere Study (SAS) and was focused on studying the interactions between biogenic and anthropogenic emissions to form secondary pollutants. Read More

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http://dx.doi.org/10.5194/amt-9-3063-2016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5880326PMC
July 2016
1 Read

Uncertainties in cloud phase and optical thickness retrievals from the Earth Polychromatic Imaging Camera (EPIC).

Atmos Meas Tech 2016 26;9(4):1785-1797. Epub 2016 Apr 26.

NASA Goddard Space Flight Center, Greenbelt, Maryland, USA.

This paper presents an investigation of the expected uncertainties of a single channel cloud optical thickness (COT) retrieval technique, as well as a simple cloud temperature threshold based thermodynamic phase approach, in support of the Deep Space Climate Observatory (DSCOVR) mission. DSCOVR cloud products will be derived from Earth Polychromatic Imaging Camera (EPIC) observations in the ultraviolet and visible spectra. Since EPIC is not equipped with a spectral channel in the shortwave or mid-wave infrared that is sensitive to cloud effective radius (CER), COT will be inferred from a single visible channel with the assumption of appropriate CER values for liquid and ice phase clouds. Read More

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http://dx.doi.org/10.5194/amt-9-1785-2016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5880043PMC
April 2016
2 Reads

Cirrus cloud optical and microphysical property retrievals from eMAS during SEACRS using bi-spectral reflectance measurements within the 1.88 μm water vapor absorption band.

Atmos Meas Tech 2016 20;9(4):1743-1753. Epub 2016 Apr 20.

Earth System Science Interdisciplinary Center, University of Maryland - College Park, College Park, Maryland, USA.

Previous bi-spectral imager retrievals of cloud optical thickness (COT) and effective particle radius (CER) based on the Nakajima and King (1990) approach, such as those of the operational MODIS cloud optical property retrieval product (MOD06), have typically paired a non-absorbing visible or near-infrared wavelength, sensitive to COT, with an absorbing shortwave or midwave infrared wavelength sensitive to CER. However, in practice it is only necessary to select two spectral channels that exhibit a strong contrast in cloud particle absorption. Here it is shown, using eMAS observations obtained during NASA's SEACRS field campaign, that selecting two absorbing wavelength channels within the broader 1. Read More

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http://dx.doi.org/10.5194/amt-9-1743-2016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5880280PMC

Controlled weather balloon ascents and descents for atmospheric research and climate monitoring.

Atmos Meas Tech 2016 7;9:929-938. Epub 2016 Mar 7.

Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, USA.

In situ upper-air measurements are often made with instruments attached to weather balloons launched at the surface and lifted into the stratosphere. Present-day balloon-borne sensors allow near-continuous measurements from the Earth's surface to about 35 km (3-5 hPa), where the balloons burst and their instrument payloads descend with parachutes. It has been demonstrated that ascending weather balloons can perturb the air measured by very sensitive humidity and temperature sensors trailing behind them, particularly in the upper troposphere and lower stratosphere (UTLS). Read More

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https://www.atmos-meas-tech.net/9/929/2016/
Publisher Site
http://dx.doi.org/10.5194/amt-9-929-2016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5734649PMC
March 2016
3 Reads

UTLS water vapour from SCIAMACHY limb measurementsV3.01 (2002-2012).

Atmos Meas Tech 2016 18;9:133-158. Epub 2016 Jan 18.

Institute of Environmental Physics - IUP, University of Bremen, Bremen, Germany.

The SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) aboard the Envisat satellite provided measurements from August 2002 until April 2012. SCIAMACHY measured the scattered or direct sunlight using different observation geometries. The limb viewing geometry allows the retrieval of water vapour at about 10-25 km height from the near-infrared spectral range (1353-1410 nm). Read More

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http://dx.doi.org/10.5194/amt-9-133-2016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5734655PMC
January 2016
5 Reads

Advancements, measurement uncertainties, and recent comparisons of the NOAA frost point hygrometer.

Atmos Meas Tech 2016 5;9(9):4295-4310. Epub 2016 Sep 5.

Physikalisch-Technische Bundesanstalt, Braunschweig, Germany.

The NOAA frost point hygrometer (FPH) is a balloon-borne instrument flown monthly at three sites to measure water vapor profiles up to 28 km. The FPH record from Boulder, Colorado, is the longest continuous stratospheric water vapor record. The instrument has an uncertainty in the stratosphere that is < 6 % and up to 12 % in the troposphere. Read More

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http://dx.doi.org/10.5194/amt-9-4295-2016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5571835PMC
September 2016
3 Reads

First eddy covariance flux measurements by PTR-TOF.

Atmos Meas Tech 2010 Mar;3(2):387-395

Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Innsbruck, Austria.

The recently developed PTR-TOF instrument was evaluated to measure methanol fluxes emitted from grass land using the eddy covariance method. The high time resolution of the PTR-TOF allowed storing full mass spectra up to 315 with a frequency of 10 Hz. Three isobaric ions were found at a nominal mass of 33 due to the high mass resolving power of the PTR-TOF. Read More

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http://dx.doi.org/10.5194/amt-3-387-2010DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3898015PMC
March 2010
1 Read
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