Diurnal, seasonal and long-term variations of global formaldehyde columns inferred from combined OMI and GOME-2 observations

Abstract. We present the new version (v14) of the BIRA-IASB algorithm for the retrieval of formaldehyde (H2CO) columns from spaceborne UV–visible sensors. Applied to OMI measurements from Aura and to GOME-2 measurements from MetOp-A and MetOp-B, this algorithm is used to produce global distributions of H2CO representative of mid-morning and early afternoon conditions. Its main features include (1) a new iterative DOAS scheme involving three fitting intervals to better account for the O2–O2 absorption, (2) the use of earthshine radiances averaged in the equatorial Pacific as reference spectra, and (3) a destriping correction and background normalisation resolved in the across-swath position. For the air mass factor calculation, a priori vertical profiles calculated by the IMAGES chemistry transport model at 09:30 and 13:30 LT are used. Although the resulting GOME-2 and OMI H2CO vertical columns are found to be highly correlated, some systematic differences are observed. Afternoon columns are generally larger than morning ones, especially in mid-latitude regions. In contrast, over tropical rainforests, morning H2CO columns significantly exceed those observed in the afternoon. These differences are discussed in terms of the H2CO column variation between mid-morning and early afternoon, using ground-based MAX-DOAS measurements available from seven stations in Europe, China and Africa. Validation results confirm the capacity of the combined satellite measurements to resolve diurnal variations in H2CO columns. Furthermore, vertical profiles derived from MAX-DOAS measurements in the Beijing area and in Bujumbura are used for a more detailed validation exercise. In both regions, we find an agreement better than 15 % when MAX-DOAS profiles are used as a priori for the satellite retrievals. Finally, regional trends in H2CO columns are estimated for the 2004–2014 period using SCIAMACHY and GOME-2 data for morning conditions, and OMI for early afternoon conditions. Consistent features are observed, such as an increase of the columns in India and central–eastern China, and a decrease in the eastern US and Europe. We find that the higher horizontal resolution of OMI combined with a better sampling and a more favourable illumination at midday allow for more significant trend estimates, especially over Europe and North America. Importantly, in some parts of the Amazonian forest, we observe with both time series a significant downward trend in H2CO columns, spatially correlated with areas affected by deforestation.

[1]  John P. Burrows,et al.  RING EFFECT: IMPACT OF ROTATIONAL RAMAN SCATTERING ON RADIATIVE TRANSFER IN EARTH’S ATMOSPHERE , 1998 .

[2]  J. Burrows,et al.  An improved glyoxal retrieval from OMI measurements , 2014 .

[3]  Henk Eskes,et al.  TROPOMI on the ESA Sentinel-5 Precursor: A GMES mission for global observations of the atmospheric composition for climate, air quality and ozone layer applications , 2012 .

[4]  M. V. Roozendael,et al.  FRESCO+: an improved O 2 A-band cloud retrieval algorithm for tropospheric trace gas retrievals , 2008 .

[5]  Nicolas Theys,et al.  Global observations of tropospheric BrO columns using GOME-2 satellite data , 2010 .

[6]  Trissevgeni Stavrakou,et al.  Trend detection in satellite observations of formaldehyde tropospheric columns , 2010 .

[7]  Alexis Merlaud,et al.  Ground-based FTIR and MAX-DOAS observations of formaldehyde at Réunion Island and comparisons with satellite and model data , 2009 .

[8]  M. Saunois,et al.  The formaldehyde budget as seen by a global-scale multi-constraint and multi-species inversion system , 2012 .

[9]  Thomas P. Kurosu,et al.  Satellite observations of formaldehyde over North America from GOME , 2000 .

[10]  John P. Burrows,et al.  GOME-2 observations of oxygenated VOCs: what can we learn from the ratio glyoxal to formaldehyde on a global scale? , 2010 .

[11]  J. Curry,et al.  Analysis of satellite-derived Arctic tropospheric BrO columns in conjunction with aircraft measurements during ARCTAS and ARCPAC , 2011 .

[12]  J. Burrows,et al.  Simultaneous global observations of glyoxal and formaldehyde from space , 2006 .

[13]  Robert J. D. Spurr,et al.  Air-mass factor formulation for spectroscopic measurements from satellites: application to formaldeh , 2001 .

[14]  Christian Hermans,et al.  Four years of ground-based MAX-DOAS observations of HONO and NO 2 in the Beijing area , 2012 .

[15]  Ryan Thalman,et al.  Temperature dependent absorption cross-sections of O2-O2 collision pairs between 340 and 630 nm and at atmospherically relevant pressure. , 2013, Physical chemistry chemical physics : PCCP.

[16]  J. Brion,et al.  Ozone UV spectroscopy I: Absorption cross-sections at room temperature , 1992 .

[17]  I. D. Smedt,et al.  Characterisation of GOME-2 formaldehyde retrieval sensitivity , 2012 .

[18]  Can Li,et al.  A new method for global retrievals of HCHO total columns from the Suomi National Polar‐orbiting Partnership Ozone Mapping and Profiler Suite , 2015 .

[19]  Henk Eskes,et al.  Twelve years of global observations of formaldehyde in the troposphere using GOME and SCIAMACHY sensors , 2008 .

[20]  D. Jacob,et al.  Isoprene emissions in Africa inferred from OMI observations of formaldehyde columns. , 2012, Atmospheric chemistry and physics.

[21]  I. D. Smedt,et al.  Long-term global observations of tropospheric formaldehyde retrieved from spaceborne nadir UV sensors , 2011 .

[22]  Glen Jaross,et al.  Validation of Ozone Monitoring Instrument level 1b data products , 2008 .

[23]  R. Spurr.  LIDORT and VLIDORT: Linearized pseudo-spherical scalar and vector discrete ordinate radiative transfer models for use in remote sensing retrieval problems , 2008 .

[24]  Kelly Chance,et al.  Can a "state of the art" chemistry transport model simulate Amazonian tropospheric chemistry? , 2011 .

[25]  Geert K. Moortgat,et al.  Temperature dependence of the absorption cross sections of formaldehyde between 223 and 323 K in the wavelength range 225–375 nm , 2000 .

[26]  Barbara Barletta,et al.  Space‐based formaldehyde measurements as constraints on volatile organic compound emissions in east and south Asia and implications for ozone , 2007 .

[27]  A. Arneth,et al.  Top‐down isoprene emissions over tropical South America inferred from SCIAMACHY and OMI formaldehyde columns , 2013 .

[28]  Johannes Orphal,et al.  New ultraviolet absorption cross-sections of BrO at atmospheric temperatures measured by time-windowing Fourier transform spectroscopy , 2004 .

[29]  J. Brion,et al.  Absorption Spectra Measurements for the Ozone Molecule in the 350–830 nm Region , 1998 .

[30]  Andreas Hilboll,et al.  Long-term changes of tropospheric NO 2 over megacities derived from multiple satellite instruments , 2012 .

[31]  Martin Wild,et al.  Isoprene emissions over Asia 1979-2012: Impact of climate and land-use changes , 2013 .

[32]  Pieter Valks,et al.  Operational total and tropospheric NO 2 column retrieval for GOME-2 , 2011 .

[33]  Nicolas Theys,et al.  Improved retrieval of global tropospheric formaldehyde columns from GOME-2/MetOp-A addressing noise reduction and instrumental degradation issues , 2012 .

[34]  Christine Wiedinmyer,et al.  Quantifying the Seasonal and Interannual Variability of North American Isoprene Emissions using Satellite Observations of Formaldehyde Column , 2005 .

[35]  Glen Jaross,et al.  Ozone monitoring instrument calibration , 2006, IEEE Transactions on Geoscience and Remote Sensing.

[36]  F. Hendrick,et al.  A simple and versatile cloud-screening method for MAX-DOAS retrievals , 2014 .

[37]  Greet Janssens-Maenhout,et al.  Emissions of air pollutants and greenhouse gases over Asian regions during 2000–2008: Regional Emission inventory in ASia (REAS) version 2 , 2013 .

[38]  GOME-2 on MetOp-A Support for Analysis of GOME-2 In-Orbit Degradation and Impacts on Level 2 Data Products Final Report , 2011 .

[39]  Andreas Hilboll,et al.  An improved NO 2 retrieval for the GOME-2 satellite instrument , 2011 .

[40]  K. F. Boersma,et al.  OMI tropospheric NO 2 air mass factors over South America: effects of biomass burning aerosols , 2015 .

[41]  Renske Timmermans,et al.  Synergistic use of OMI NO2 tropospheric columns and LOTOS–EUROS to evaluate the NOx emission trends across Europe , 2014 .

[42]  M. Shao,et al.  Understanding primary and secondary sources of ambient carbonyl compounds in Beijing using the PMF model , 2013 .

[43]  Paul Ingmann,et al.  Requirements for the GMES Atmosphere Service and ESA's implementation concept: Sentinels-4/-5 and -5p , 2012 .

[44]  I. D. Smedt,et al.  Glyoxal vertical columns from GOME-2 backscattered light measurements and comparisons with a global model , 2010 .

[45]  J. Burrows,et al.  The continental source of glyoxal estimated by the synergistic use of spaceborne measurements and inverse modelling , 2009 .

[46]  Quintus Kleipool,et al.  Earth surface reflectance climatology from 3 years of OMI data , 2008 .

[47]  Xiong Liu,et al.  Updated Smithsonian Astrophysical Observatory Ozone Monitoring Instrument (SAO OMI) formaldehyde retrieval , 2015 .

[48]  I. D. Smedt,et al.  Inter-annual variations in satellite observations of nitrogen dioxide and formaldehyde over India , 2015 .

[49]  I. D. Smedt,et al.  Evaluating the performance of pyrogenic and biogenic emission inventories against one decade of space-based formaldehyde columns , 2008 .

[50]  I. D. Smedt,et al.  Spatio-temporal analyses of formaldehyde over Pakistan by using SCIAMACHY and GOME-2 observations , 2015 .

[51]  J. Burrows,et al.  Satellite observations of long range transport of a large BrO plume in the Arctic , 2009 .

[52]  Gabriele Curci,et al.  Estimating European volatile organic compound emissions using satellite observations of formaldehyde from the Ozone Monitoring Instrument , 2010 .

[53]  Nicolas Theys,et al.  Sulfur dioxide vertical column DOAS retrievals from the Ozone Monitoring Instrument: Global observations and comparison to ground‐based and satellite data , 2015 .

[54]  J. Brion,et al.  Ozone UV spectroscopy. II. Absorption cross-sections and temperature dependence , 1995 .

[55]  U. Platt,et al.  Extending differential optical absorption spectroscopy for limb measurements in the UV , 2010 .

[56]  John P. Burrows,et al.  On the improvement of NO 2 satellite retrievals – aerosol impact on the airmass factors , 2009 .

[57]  Xiong Liu,et al.  A new interpretation of total column BrO during Arctic spring , 2010 .

[58]  John P. Burrows,et al.  MAX-DOAS measurements of formaldehyde in the Po-Valley , 2004 .

[59]  Nicolas Theys,et al.  Evaluation of tropospheric SO 2 retrieved from MAX-DOAS measurements in Xianghe, China , 2014 .

[60]  C. McLinden,et al.  Toxic volatile organic air pollutants across Canada: multi-year concentration trends, regional air quality modelling and source apportionment , 2016, Journal of Atmospheric Chemistry.

[61]  D. Jacob,et al.  Anthropogenic emissions of highly reactive volatile organic compounds in eastern Texas inferred from oversampling of satellite (OMI) measurements of HCHO columns , 2014 .

[62]  Dominik Brunner,et al.  Eight-component retrievals from ground-based MAX-DOAS observations , 2011 .

[63]  Trissevgeni Stavrakou,et al.  Global emissions of non-methane hydrocarbons deduced from SCIAMACHY formaldehyde columns through 2003-2006 , 2009 .

[64]  Glyoxal retrieval from the Ozone Monitoring Instrument , 2014 .

[65]  Henk Eskes,et al.  Averaging kernels for DOAS total-column satellite retrievals , 2003 .

[66]  Heikki Saari,et al.  The ozone monitoring instrument , 2006, IEEE Transactions on Geoscience and Remote Sensing.

[67]  Piet Stammes,et al.  Effective cloud fractions from the Ozone Monitoring Instrument: Theoretical framework and validation , 2008 .

[68]  Xiong Liu,et al.  Smithsonian Astrophysical Observatory Ozone Mapping and Profiler Suite (SAO OMPS) formaldehyde retrieval , 2015 .

[69]  J. Randerson,et al.  Global fire emissions and the contribution of deforestation, savanna, forest, agricultural, and peat fires (1997-2009) , 2010 .

[70]  Steffen Beirle,et al.  Tropospheric No 2 Vertical Column Densities over Beijing Printer-friendly Version Interactive Discussion Atmospheric Chemistry and Physics Discussions Tropospheric No 2 Vertical Column Densities over Beijing: Results of the First Three-years of Ground-based Max-doas Measurements (2008–2011) and Sate , 2022 .

[71]  Christian Hermans,et al.  MAX-DOAS observations of aerosols, formaldehyde and nitrogen dioxide in the Beijing area: comparison of two profile retrieval approaches , 2014 .

[72]  K. F. Boersma,et al.  Spatial distribution of isoprene emissions from North America derived from formaldehyde column measurements by the OMI satellite sensor , 2008 .

[73]  J. Randerson,et al.  Analysis of daily, monthly, and annual burned area using the fourth‐generation global fire emissions database (GFED4) , 2013 .

[74]  K. Boersma,et al.  Key chemical NOx sink uncertainties and how they influence top-down emissions of nitrogen oxides , 2013 .

[75]  G. Carmichael,et al.  Asian emissions in 2006 for the NASA INTEX-B mission , 2009 .

[76]  Henk Eskes,et al.  An improved tropospheric NO 2 column retrieval algorithm for the Ozone Monitoring Instrument , 2011 .

[77]  A. Hahne,et al.  GOME-2 – Metop ’ s Second-Generation Sensor for Operational Ozone Monitoring , 2000 .

[78]  Kelly Chance,et al.  An improved high-resolution solar reference spectrum for earth's atmosphere measurements in the ultraviolet, visible, and near infrared , 2010 .

[79]  James F. Gleason,et al.  An improved retrieval of tropospheric nitrogen dioxide from GOME , 2002 .

[80]  F. Hendrick,et al.  Multiple wavelength retrieval of tropospheric aerosol optical properties from MAXDOAS measurements in Beijing , 2010 .

[81]  R. Quentin Grafton,et al.  global surface temperature , 2012 .

[82]  J. Hansen,et al.  GLOBAL SURFACE TEMPERATURE CHANGE , 2010 .

[83]  Hisahiro Takashima,et al.  MAX-DOAS formaldehyde slant column measurements during CINDI: intercomparison and analysis improvement , 2012 .

[84]  Ann Carine Vandaele,et al.  High-resolution Fourier transform measurement of the NO2 visible and near-infrared absorption cross sections: Temperature and pressure effects , 2002 .

[85]  J. Pereira,et al.  Global wildland fire emissions from 1960 to 2000 , 2008 .