The Berkeley High Resolution Tropospheric NO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; product

Laughner, Joshua L.; Zhu, Qindan; Cohen, R. C.

doi:10.5194/essd-10-2069-2018

Cited by 38 publications

(70 citation statements)

References 95 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Data availability. All datasets are publicly available online: GeoTASO data are archived at https://www-air.larc.nasa.gov/ cgi-bin/ArcView/lmos (Janz et al, 2019), Pandora NO 2 data are found at http://judd2019.pandonia-global-network.org/ (last access: 4 November 2019) and produced following https://www.pandonia-global-network.org/wp-content/uploads/ 2019/11/BlickSoftwareSuite_Manual_v1-7.pdf (LuftBlick, 2017), and OMI data are from Laughner et al (2018b).…”

Section: Discussionmentioning

confidence: 99%

“…OMI is a space-based UV-VIS instrument launched in 2004 aboard the EOS-Aura satellite in a sun-synchronous orbit with an Equator crossing time in the early afternoon (Levelt et al, 2006). This work uses the NASA standard product (SP) version 3 and the Berkeley High Resolution (BEHR) product (Russell et al, 2011;Laughner et al, 2018bLaughner et al, , 2019 to assess how their tropospheric column retrievals compare with measurements from Pandora spectrometers deployed during summer 2017 in the LMOS and the LA Basin domains. The two vertical column products are based on the same slant columns (produced by the SP retrieval), but they differ in their a priori inputs for the tropospheric air mass factor calculation.…”

Section: Ozone Monitoring Instrument (Omi)mentioning

confidence: 99%

See 1 more Smart Citation

Evaluating the impact of spatial resolution on tropospheric NO2 column comparisons within urban areas using high-resolution airborne data

et al. 2019

View full text Add to dashboard Cite

NASA deployed the GeoTASO airborne UVvisible spectrometer in May-June 2017 to produce highresolution (approximately 250 m × 250 m) gapless NO 2 datasets over the western shore of Lake Michigan and over the Los Angeles Basin. The results collected show that the airborne tropospheric vertical column retrievals compare well with ground-based Pandora spectrometer column NO 2 observations (r 2 = 0.91 and slope of 1.03). Apparent disagreements between the two measurements can be sensitive to the coincidence criteria and are often associated with large local variability, including rapid temporal changes and spatial heterogeneity that may be observed differently by the sunward-viewing Pandora observations. The gapless mapping strategy executed during the 2017 GeoTASO flights provides data suitable for averaging to coarser areal resolutions to simulate satellite retrievals. As simulated satellite pixel area increases to values typical of TEMPO (Tropospheric Emissions: Monitoring Pollution), TROPOMI (TRO-POspheric Monitoring Instrument), and OMI (Ozone Monitoring Instrument), the agreement with Pandora measurements degraded, particularly for the most polluted columns as localized large pollution enhancements observed by Pandora and GeoTASO are spatially averaged with nearby less-polluted locations within the larger area representative of the satellite spatial resolutions (aircraft-to-Pandora slope: TEMPO scale = 0.88; TROPOMI scale = 0.77; OMI scale = 0.57). In these two regions, Pandora and TEMPO or TROPOMI have the potential to compare well at least up to pollution scales of 30 × 10 15 molecules cm −2 . Two publicly available OMI tropospheric NO 2 retrievals are found to be biased low with respect to these Pandora observations. However, the agreement improves when higher-resolution a priori inputs are used for the tropospheric air mass factor calculation (NASA V3 standard product slope = 0.18 and Berkeley High Resolution product slope = 0.30). Overall, this work explores best practices for satellite validation strategies with Pandora direct-sun observations by showing the sensitivity to product spatial resolution and demonstrating how the high-spatial-resolution NO 2 data retrieved from airborne spectrometers, such as GeoTASO, can be used with high-temporal-resolution ground-based column observationsPublished by Copernicus Publications on behalf of the European Geosciences Union. 6092 L. M. Judd et al.: Impact of spatial resolution on tropospheric NO 2 column comparisons to evaluate the influence of spatial heterogeneity on validation results.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Ozone Monitoring Instrument (Omi)mentioning

confidence: 99%

Evaluating the impact of spatial resolution on tropospheric NO2 column comparisons within urban areas using high-resolution airborne data

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Celarier et al, 2008;Kramer et al, 2008;Chen et al, 2009;Irie et al, 2012;Ma et al, 2013;Wu et al, 2013;Kanaya et al, 2014;Wang et al, 2017;Drosoglou et al, 2017Drosoglou et al, , 2018. Other possible explanations include the uncertainties in the applied satellite retrieval assumptions, such as the choices of surface albedo, a priori NO 2 profiles, or cloud and aerosol treatment (Boersma et al, 2004Leitão et al, 2010;Heckel et al, 2011;Lin et al, 2014Lin et al, , 2015. The best agreement is generally obtained in the case of suburban and remote stations, but difficulties may arise when small local sources are present in a remote location, such as Réu-nion island or Bujumbura Gielen et al, 2017).…”

Section: Uncertainty Estimates For Gome-2 Total and Tropospheric Nomentioning

confidence: 99%

An improved total and tropospheric NO2 column retrieval for GOME-2

et al. 2019

View full text Add to dashboard Cite

Abstract. An improved algorithm for the retrieval of total and tropospheric nitrogen dioxide (NO2) columns from the Global Ozone Monitoring Experiment-2 (GOME-2) is presented. The refined retrieval will be implemented in a future version of the GOME Data Processor (GDP) as used by the EUMETSAT Satellite Application Facility on Atmospheric Composition and UV Radiation (AC-SAF). The first main improvement is the application of an extended 425–497 nm wavelength fitting window in the differential optical absorption spectroscopy (DOAS) retrieval of the NO2 slant column density, based on which initial total NO2 columns are computed using stratospheric air mass factors (AMFs). Updated absorption cross sections and a linear offset correction are used for the large fitting window. An improved slit function treatment is applied to compensate for both long-term and in-orbit drift of the GOME-2 slit function. Compared to the current operational (GDP 4.8) dataset, the use of these new features increases the NO2 columns by ∼1–3×1014 molec cm2 and reduces the slant column error by ∼24 %. In addition, the bias between GOME-2A and GOME-2B measurements is largely reduced by adopting a new level 1b data version in the DOAS retrieval. The retrieved NO2 slant columns show good consistency with the Quality Assurance for Essential Climate Variables (QA4ECV) retrieval with a good overall quality. Second, the STRatospheric Estimation Algorithm from Mainz (STREAM), which was originally developed for the TROPOspheric Monitoring Instrument (TROPOMI) instrument, was optimised for GOME-2 measurements to determine the stratospheric NO2 column density. Applied to synthetic GOME-2 data, the estimated stratospheric NO2 columns from STREAM shows good agreement with the a priori truth. An improved latitudinal correction is introduced in STREAM to reduce the biases over the subtropics. Applied to GOME-2 measurements, STREAM largely reduces the overestimation of stratospheric NO2 columns over polluted regions in the GDP 4.8 dataset. Third, the calculation of AMF applies an updated box-air-mass factor (box-AMF) look-up table (LUT) calculated using the latest version 2.7 of the Vector-LInearized Discrete Ordinate Radiative Transfer (VLIDORT) model with an increased number of reference points and vertical layers, a new GOME-2 surface albedo climatology, and improved a priori NO2 profiles obtained from the TM5-MP chemistry transport model. A large effect (mainly enhancement in summer and reduction in winter) on the retrieved tropospheric NO2 columns by more than 10 % is found over polluted regions. To evaluate the GOME-2 tropospheric NO2 columns, an end-to-end validation is performed using ground-based multiple-axis DOAS (MAXDOAS) measurements. The validation is illustrated for six stations covering urban, suburban, and background situations. Compared to the GDP 4.8 product, the new dataset presents improved agreement with the MAXDOAS measurements for all the stations.

show abstract

“…This trend matches satellite observations of NO 2 over the continental United States. Figure 8 shows the cumulative frequency distribution of summertime tropospheric NO 2 columns from 2005-2007 and 2015-2017 using the BErkeley High-Resolution (BEHR) v3.0A retrieval (Laughner et al, 2018a) of slantcolumn measurements from ozone monitoring instrument (OMI). Over this time, the highest percentiles of NO 2 concentrations have decreased and the lowest percentiles increased, leading to a significantly narrower distribution of NO 2 concentrations.…”

Section: Impacts Of the Transition From The Hno 3 To The Rono 2 Regimementioning

confidence: 99%

The changing role of organic nitrates in the removal and transport of NOx

Romer¹,

Zare²,

Cohen³

2020

Atmos. Chem. Phys.

Self Cite

View full text Add to dashboard Cite

A better understanding of the chemistry of nitrogen oxides (NO x ) is crucial to effectively reducing air pollution and predicting future air quality. The response of NO x lifetime to perturbations in emissions or in the climate system is set in large part by whether NO x loss occurs primarily by the direct formation of HNO 3 or through the formation of alkyl and multifunctional nitrates (RONO 2 ). Using 15 years of detailed in situ observations, we show that in the summer daytime continental boundary layer the relative importance of these two pathways can be well approximated by the relative likelihood that OH will react with NO 2 or instead with a volatile organic compound (VOC). Over the past decades, changes in anthropogenic emissions of both NO x and VOCs have led to a significant increase in the overall importance of RONO 2 chemistry to NO x loss. We find that this shift is associated with a decreased effectiveness of NO x emissions reductions on ozone production in polluted areas and increased transport of NO x from source to receptor regions. This change in chemistry, combined with changes in the spatial pattern of NO x emissions, is observed to be leading to a flatter distribution of NO 2 across the United States, potentially transforming ozone air pollution from a local issue into a regional one.

show abstract

The Berkeley High Resolution Tropospheric NO<sub>2</sub> product

Cited by 38 publications

References 95 publications

Evaluating the impact of spatial resolution on tropospheric NO<sub>2</sub> column comparisons within urban areas using high-resolution airborne data

Evaluating the impact of spatial resolution on tropospheric NO<sub>2</sub> column comparisons within urban areas using high-resolution airborne data

An improved total and tropospheric NO<sub>2</sub> column retrieval for GOME-2

The changing role of organic nitrates in the removal and transport of NO<sub><i>x</i></sub>

Contact Info

Product

Resources

About

The Berkeley High Resolution Tropospheric NO&lt;sub&gt;2&lt;/sub&gt; product

Cited by 38 publications

References 95 publications

Evaluating the impact of spatial resolution on tropospheric NO&lt;sub&gt;2&lt;/sub&gt; column comparisons within urban areas using high-resolution airborne data

Evaluating the impact of spatial resolution on tropospheric NO&lt;sub&gt;2&lt;/sub&gt; column comparisons within urban areas using high-resolution airborne data

An improved total and tropospheric NO&lt;sub&gt;2&lt;/sub&gt; column retrieval for GOME-2

The changing role of organic nitrates in the removal and transport of NO&lt;sub&gt;&lt;i&gt;x&lt;/i&gt;&lt;/sub&gt;

Contact Info

Product

Resources

About

The Berkeley High Resolution Tropospheric NO<sub>2</sub> product

Evaluating the impact of spatial resolution on tropospheric NO<sub>2</sub> column comparisons within urban areas using high-resolution airborne data

Evaluating the impact of spatial resolution on tropospheric NO<sub>2</sub> column comparisons within urban areas using high-resolution airborne data

An improved total and tropospheric NO<sub>2</sub> column retrieval for GOME-2

The changing role of organic nitrates in the removal and transport of NO<sub><i>x</i></sub>