scholarly journals Seasonal variations of CO and HCN in the troposphere measured by solar absorption spectroscopy over Poker Flat, Alaska

2005 ◽  
Vol 32 (19) ◽  
pp. n/a-n/a ◽  
Author(s):  
Yasuko J. Kasai ◽  
Akiko Kagawa ◽  
Nicholas Jones ◽  
Akimitsu Fujiwara ◽  
Koji Seki ◽  
...  
Keyword(s):  
Absorption Spectroscopy ◽  
Seasonal Variations ◽  
Solar Absorption

Airborne observations of the 1992 arctic winter stratosphere by FTIR solar absorption spectroscopy

1993 ◽  
Author(s):  
Geoffrey C. Toon ◽  
J. F. Blavier ◽  
J. N. Solario ◽  
J. M. Szeto
Keyword(s):  
Absorption Spectroscopy ◽  
Solar Absorption

scholarly journals First detection of meso-thermospheric Nitric Oxide (NO) by ground-based FTIR solar absorption spectroscopy

2006 ◽  
Vol 33 (3) ◽  
Author(s):  
A. Wiacek ◽  
N. B. Jones ◽  
K. Strong ◽  
J. R. Taylor ◽  
R. L. Mittermeier ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Absorption Spectroscopy ◽  
Solar Absorption

scholarly journals Formaldehyde total column densities over Mexico City: comparison between multi-axis differential optical absorption spectroscopy and solar-absorption Fourier transform infrared measurements

2021 ◽  
Vol 14 (1) ◽  
pp. 595-613
Author(s):  
Claudia Rivera Cárdenas ◽  
Cesar Guarín ◽  
Wolfgang Stremme ◽  
Martina M. Friedrich ◽  
Alejandro Bezanilla ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Optical Absorption ◽  
Mexico City ◽  
Absorption Spectroscopy ◽  
Fourier Transform Infrared ◽  
Differential Optical Absorption Spectroscopy ◽  
Urban Site ◽  
Optical Absorption Spectroscopy ◽  
Solar Absorption ◽  
Total Column

Abstract. Formaldehyde (HCHO) total column densities over the Mexico City metropolitan area (MCMA) were retrieved using two independent measurement techniques: multi-axis differential optical absorption spectroscopy (MAX-DOAS) and Fourier transform infrared (FTIR) spectroscopy. For the MAX-DOAS measurements, the software QDOAS was used to calculate differential slant column densities (dSCDs) from the measured spectra and subsequently the Mexican MAX-DOAS fit (MMF) retrieval code to convert from dSCDs to vertical column densities (VCDs). The direct solar-absorption spectra measured with FTIR were analyzed using the PROFFIT (PROFile FIT) retrieval code. Typically the MAX-DOAS instrument reports higher VCDs than those measured with FTIR, in part due to differences found in the ground-level sensitivities as revealed from the retrieval diagnostics from both instruments, as the FTIR and the MAX-DOAS information do not refer exactly to the same altitudes of the atmosphere. Three MAX-DOAS datasets using measurements conducted towards the east, west or both sides of the measurement plane were evaluated with respect to the FTIR results. The retrieved MAX-DOAS HCHO VCDs where 6 %, 8 % and 28 % larger than the FTIR measurements which, supported with satellite data, indicates a large horizontal inhomogeneity in the HCHO abundances. The temporal change in the vertical distribution of this pollutant, guided by the evolution of the mixing-layer height, affects the comparison of the two retrievals with different sensitivities (total column averaging kernels). In addition to the reported seasonal and diurnal variability of HCHO columns within the urban site, background data from measurements at a high-altitude station, located only 60 km away, are presented.

scholarly journals Latitudinal variations of trace gas concentrations in the free troposphere measured by solar absorption spectroscopy during a ship cruise

2000 ◽  
Vol 105 (D1) ◽  
pp. 1337-1349 ◽  
Author(s):  
J. Notholt ◽  
G. C. Toon ◽  
C. P. Rinsland ◽  
N. S. Pougatchev ◽  
N. B. Jones ◽  
...  
Keyword(s):  
Absorption Spectroscopy ◽  
Trace Gas ◽  
Free Troposphere ◽  
Solar Absorption ◽  
Latitudinal Variations

Composition measurements of the 1989 Arctic winter stratosphere by airborne infrared solar absorption spectroscopy

1992 ◽  
Vol 97 (D8) ◽  
pp. 7939 ◽  
Author(s):  
G. C. Toon ◽  
C. B. Farmer ◽  
P. W. Schaper ◽  
L. L. Lowes ◽  
R. H. Norton
Keyword(s):  
Absorption Spectroscopy ◽  
Solar Absorption ◽  
Composition Measurements

Mountain polar stratospheric cloud measurements by Ground Based FTIR Solar Absorption Spectroscopy

2001 ◽  
Vol 28 (11) ◽  
pp. 2189-2192 ◽  
Author(s):  
Michael Höpfner ◽  
Thomas Blumenstock ◽  
Frank Hase ◽  
Alexandra Zimmermann ◽  
Harald Flentje ◽  
...  
Keyword(s):  
Absorption Spectroscopy ◽  
Solar Absorption ◽  
Polar Stratospheric Cloud

Mobile ground-based remote sensing of atmospheric CO2, CH4, and CO column densities above the Pacific Ocean

2020 ◽  
Author(s):  
Marvin Knapp ◽  
Ralph Kleinschek ◽  
Benedikt Hemmer ◽  
Ralph Pfeifer ◽  
Frank Hase ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Absorption Spectroscopy ◽  
Short Wave ◽  
Research Vessel ◽  
Model Data ◽  
Direct Sunlight ◽  
Solar Absorption ◽  
The Pacific ◽  
Solar Tracker ◽  
Gas Measurements

<p>Validation opportunities for model data and satellite observations in the short-wave infra-red spectral range are still sparse above the oceans. To provide such opportunities, we qualify a Fourier-transform spectrometer (FTS) for the regular use on ships. We use the EM27/SUN FTS [1] in direct-sunlight measurement geometry to retrieve total column densities of carbon dioxide (CO<sub>2</sub>), methane (CH<sub>4</sub>), and carbon monoxide (CO) [2] with solar absorption spectroscopy.<br>Performing direct-sunlight measurements from a moving platform poses significant challenges to the solar tracking. We use a solar tracker that compensates the vessel's movements in real time, keeping the pointing of the instrument relative to the center of the sun better than 0.05° for more than 99 % of the time [3]. The solar tracker is part of a newly developed enclosure that allows automated measurements and withstands environmental factors such as rain, humidity, and sea spray.<br>The instrument was deployed on board the German research vessel <em>RV Sonne</em> during the MORE-2 (Measuring Oceanic REferences 2) campaign on a longitudinal transect from Vancouver (Canada) to Singapore in June 2019. During the campaign we recorded 33800 direct sunlight spectra from which column-averaged dry-air mole fractions of CO<sub>2</sub>, CH<sub>4</sub>, and CO are retrieved. Our results are calibrated against World Meteorological Organization standards and the columns achieve a relative precision of 0.06 %, 0.06 %, and 1.02 % for CO<sub>2</sub>, CH<sub>4</sub>, and CO, respectively.<br>We compare our records to coincident observations of the Greenhouse gases Observing SATellite (GOSAT), the Orbiting Carbon Observatory-2 (OCO-2), and the TROPOspheric Monitoring Instrument (TROPOMI). Our CO<sub>2</sub> records show a mean offset of -3.2 ± 1.1 ppm to OCO-2 and -1.4 ± 1.7 ppm to GOSAT observations. Furthermore, we find a mean CH<sub>4</sub> offset of 17 ± 6 ppb to GOSAT and a mean CO offset of 3.5 ± 2.6 ppb to TROPOMI. The Copernicus Atmosphere Monitoring Service (CAMS) provided us with model data of CH<sub>4</sub> and CO. We could show that the CO data agree well with our measurements, showing an offset of 3.5 ± 3.6 ppb.</p><p><br>[1] Gisi, M. et al.: XCO2-measurements with a tabletop FTS using solar absorption spectroscopy, Atmos. Meas. Tech., 5, 2969-2980, 2012<br>[2] Hase, F. et al.: Addition of a channel for XCO observations to a portable FTIR spectrometer for greenhouse gas measurements, Atmos. Meas. Tech., 9, 2303-2313, 2016<br>[3] Klappenbach, F. et al.: Accurate mobile remote sensing of XCO2 and XCH4 latitudinal transects from aboard a research vessel, Atmos. Meas. Tech., 8, 5023–5038, 2015</p>

Seasonal variations in AADSAS applicants

1985 ◽  
Vol 49 (6) ◽  
pp. 445-447
Author(s):  
E Solomon ◽  
D Stoll
Keyword(s):  
Seasonal Variations
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