Harmonized dataset of ozone profiles from satellite limb and occultation measurements

Abstract. In this paper, we present a HARMonized dataset of OZone profiles (HARMOZ) based on limb and occultation measurements from Envisat (GOMOS, MIPAS and SCIAMACHY), Odin (OSIRIS, SMR) and SCISAT (ACE-FTS) satellite instruments. These measurements provide high-vertical-resolution ozone profiles covering the altitude range from the upper troposphere up to the mesosphere in years 2001–2012. HARMOZ has been created in the framework of the European Space Agency Climate Change Initiative project. The harmonized dataset consists of original retrieved ozone profiles from each instrument, which are screened for invalid data by the instrument teams. While the original ozone profiles are presented in different units and on different vertical grids, the harmonized dataset is given on a common pressure grid in netCDF (network common data form)-4 format. The pressure grid corresponds to vertical sampling of ~ 1 km below 20 km and 2–3 km above 20 km. The vertical range of the ozone profiles is specific for each instrument, thus all information contained in the original data is preserved. Provided altitude and temperature profiles allow the representation of ozone profiles in number density or mixing ratio on a pressure or altitude vertical grid. Geolocation, uncertainty estimates and vertical resolution are provided for each profile. For each instrument, optional parameters, which are related to the data quality, are also included. For convenience of users, tables of biases between each pair of instruments for each month, as well as bias uncertainties, are provided. These tables characterize the data consistency and can be used in various bias and drift analyses, which are needed, for instance, for combining several datasets to obtain a long-term climate dataset. This user-friendly dataset can be interesting and useful for various analyses and applications, such as data merging, data validation, assimilation and scientific research. The dataset is available at http://www.esa-ozone-cci.org/?q=node/161 or at doi:10.5270/esa-ozone_cci-limb_occultation_profiles-2001_2012-v_1-201308.

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Harmonized dataset of ozone profiles from satellite limb and occultation measurements

Earth System Science Data Discussions ◽

10.5194/essdd-6-189-2013 ◽

2013 ◽

Vol 6 (1) ◽

pp. 189-222 ◽

Cited By ~ 1

Author(s):

V. F. Sofieva ◽

N. Rahpoe ◽

J. Tamminen ◽

E. Kyrölä ◽

N. Kalakoski ◽

...

Keyword(s):

European Space Agency ◽

Original Data ◽

Data Consistency ◽

Vertical Resolution ◽

Data Merging ◽

Space Agency ◽

Vertical Range ◽

Uncertainty Estimates ◽

User Friendly ◽

Vertical Grids

Abstract. In this paper, we present a HARMonized dataset of OZone profiles (HARMOZ) based on limb and occultation measurements from Envisat (GOMOS, MIPAS and SCIAMACHY), Odin (OSIRIS, SMR) and SCISAT (ACE-FTS) satellite instruments. These measurements provide high-vertical-resolution ozone profiles covering the altitude range from the upper troposphere up to the mesosphere in years 2001–2012. HARMOZ has been created in the framework of European Space Agency Climate Change Initiative project. The harmonized dataset consists of original retrieved ozone profiles from each instrument, which are screened for invalid data by the instrument teams. While the original ozone profiles are presented in different units and on different vertical grids, the harmonized dataset is given on a common pressure grid in netcdf format. The pressure grid corresponds to vertical sampling of ~ 1 km below 20 km and 2–3 km above 20 km. The vertical range of the ozone profiles is specific for each instrument, thus all information contained in the original data is preserved. Provided altitude and temperature profiles allow the representation of ozone profiles in number density or mixing ratio on a pressure or altitude vertical grids. Geolocation, uncertainty estimates and vertical resolution are provided for each profile. For each instrument, optional parameters, which might be related to the data quality, are also included. For convenience of users, tables of biases between each pair of instruments for each month, as well as bias uncertainties, are provided. These tables characterize the data consistency and can be used in various bias and drift analyses, which are needed, for instance, for combining several datasets to obtain a long-term climate dataset. This user-friendly dataset can be interesting and useful for various analyses and applications, such as data merging, data validation, assimilation and scientific research. Dataset is available at: http://www.esa-ozone-cci.org/?q=node/161.

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The ESA MIPAS/Envisat level2-v8 dataset: 10 years of measurements retrieved with ORM v8.22

Atmospheric Measurement Techniques ◽

10.5194/amt-14-7975-2021 ◽

2021 ◽

Vol 14 (12) ◽

pp. 7975-7998

Author(s):

Bianca Maria Dinelli ◽

Piera Raspollini ◽

Marco Gai ◽

Luca Sgheri ◽

Marco Ridolfi ◽

...

Keyword(s):

Degrees Of Freedom ◽

Michelson Interferometer ◽

European Space Agency ◽

Vertical Resolution ◽

Scientific Prototype ◽

Retrieval Error ◽

Trace Species ◽

Vertical Range ◽

Vertical Grid ◽

Level 2

Abstract. The observations acquired during the full mission of the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) instrument, aboard the European Space Agency Environmental Satellite (Envisat), have been analysed with version 8.22 of the Optimised Retrieval Model (ORM), originally developed as the scientific prototype of the ESA level-2 processor for MIPAS observations. The results of the analyses have been included into the MIPAS level-2 version 8 (level2-v8) database containing atmospheric fields of pressure, temperature, and volume mixing ratio (VMR) of MIPAS main targets H2O, O3, HNO3, CH4, N2O, and NO2, along with the minor gases CFC-11, ClONO2, N2O5, CFC-12, COF2, CCl4, CF4, HCFC-22, C2H2, CH3Cl, COCl2, C2H6, OCS, and HDO. The database covers all the measurements acquired by MIPAS in the nominal measurement mode of the full resolution (FR) part of the mission (from July 2002 to March 2004) and all the observation modes of the optimised resolution (OR) part (from January 2005 to April 2012). The number of species included in the MIPAS level2-v8 dataset makes it of particular importance for the studies of stratospheric chemistry. The database is considered by ESA the final release of the MIPAS level-2 products. The ORM algorithm is operated at the vertical grid coincident to the tangent altitudes of the observations or to a subset of them, spanning (in the nominal mode) the altitude range from 6 to 68 km in the FR phase and from 6 to 70 km in the OR period. In the latitude domain, FR profiles are spaced by about 4.7∘, while the OR profiles are spaced by about 3.7∘. For each retrieved species, the auxiliary data and the retrieval choices are described. Each product is characterised in terms of the retrieval error, spatial resolution, and “useful” vertical range in both phases of the MIPAS mission. These depend on the characteristics of the measurements (spectral and vertical resolution of the measurements), the retrieval choices (number of spectral points included in the analyses, number of altitudes included in the vertical retrieval grid), and the information content of the measurements for each trace species. For temperature, water vapour, ozone, and nitric acid, the number of degrees of freedom is significantly larger in the OR phase than in the FR one, mainly due to the finer vertical measurement grid. In the FR phase, some trace species are characterised by a smaller retrieval error with respect to the OR phase, mainly due to the larger number of spectral points used in the analyses, along with the reduced vertical resolution. The way of handling possible caveats (negative VMR, vertical grid representation) is discussed. The quality of the retrieved profiles is assessed through four criteria, two providing information on the successful convergence of the retrieval iterations, one on the capability of the retrieval to reproduce the measurements, and one on the presence of outliers. An easy way to identify and filter the problematic profiles with the information contained in the output files is provided. MIPAS level2-v8 data are available to the scientific community through the ESA portal (https://doi.org/10.5270/EN1-c8hgqx4).

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The ESA MIPAS/ENVISAT Level2-v8 dataset: 10 years of measurements retrieved with ORM v8.22

10.5194/amt-2021-215 ◽

2021 ◽

Author(s):

Bianca Maria Dinelli ◽

Piera Raspollini ◽

Marco Gai ◽

Luca Sgheri ◽

Marco Ridolfi ◽

...

Keyword(s):

Michelson Interferometer ◽

European Space Agency ◽

Vertical Resolution ◽

Scientific Prototype ◽

Data Set ◽

Retrieval Error ◽

Trace Species ◽

Vertical Range ◽

Vertical Grid ◽

Level 2

Abstract. The observations acquired during the full mission of the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) instrument, on board the European Space Agency ENVISAT satellite, have been analysed with version 8.22 of the Optimised Retrieval Model (ORM), originally developed as the scientific prototype of the ESA level 2 processor for MIPAS observations. The results of the analyses have been included into the MIPAS level 2 version 8 (level2-v8) database containing atmospheric fields of pressure, temperature and volume mixing ratio of MIPAS main targets H2O, O3, HNO3, CH4, N2O, and NO2, along with the minor gases CFC-11, ClONO2, N2O5, CFC-12, COF2, CCl4, CF4, HCFC-22, C2H2, CH3Cl, COCl2, C2H6, OCS, HDO. The database covers all the measurements acquired by MIPAS in the nominal measurement mode of the Full Resolution (FR) part of the mission (from July 2002 to March 2004) and all the observation modes of the Optimised Resolution (OR) part (from January 2005 to April 2012). The number of species included in the MIPAS level2-v8 data-set makes it of particular importance for the studies of stratospheric chemistry. The database is considered by ESA the final release of the MIPAS level 2 products. The ORM algorithm is operated at the vertical grid coincident to the tangent altitudes of the observations or to a subset of them, spanning (in the nominal mode) the altitude range from 6 to 68 km in the FR phase and from 6 to 70 km in the OR period. In the latitude domain, FR profiles are spaced by about 4.7 degrees while the OR profiles are spaced by about 3.7 degrees. For each retrieved species the auxiliary data and the retrieval choices are described. Each product is characterised in terms of the retrieval error, spatial resolution, and 'useful' vertical range in both phases of the MIPAS mission. These depend on the characteristics of the measurements (spectral and vertical resolution of the measurements), on the retrieval choices (number of spectral points included in the analyses, number of altitudes included in the vertical retrieval grid), and on the information content of the measurements for each trace species. For temperature, water vapour, ozone and nitric acid the number of degrees of freedom is significantly larger in the OR phase than in the FR one, mainly due to the finer vertical measurement grid. In the FR phase some trace species are characterised by a smaller retrieval error with respect to the OR phase, mainly due to the larger number of spectral points used in the analyses, along with the reduced vertical resolution. The way of handling possible caveats (negative VMR, vertical grid representation) is discussed. The quality of the retrieved profiles is assessed through four criteria, two providing information on the successful convergence of the retrieval iterations, one on the capability of the retrieval to reproduce the measurements, and one on the presence of outliers. An easy way to identify and filter the problematic profiles with the information contained in the output files is provided. MIPAS level2-v8 data are available to the scientific community through the ESA portal https://earth.esa.int/eogateway/.

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The MIPAS2D database of MIPAS/ENVISAT measurements retrieved with a multi-target 2-dimensional tomographic approach

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-2-2639-2009 ◽

2009 ◽

Vol 2 (5) ◽

pp. 2639-2688 ◽

Cited By ~ 2

Author(s):

B. M. Dinelli ◽

E. Arnone ◽

G. Brizzi ◽

M. Carlotti ◽

E. Castelli ◽

...

Keyword(s):

Web Sites ◽

Michelson Interferometer ◽

European Space Agency ◽

Retrieval Algorithm ◽

Satellite Measurements ◽

Full Resolution ◽

Space Agency ◽

Vertical Grid ◽

Atmospheric State ◽

Tomographic Approach

Abstract. We present a multi-year database of atmospheric state parameters retrieved for the upper tropospheric to mesospheric region from satellite measurements with a 2-dimensional tomographic approach. The full mission of the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) instrument, on board the European Space Agency ENVISAT satellite, is analyzed with the Geofit Multi-Target Retrieval (GMTR) system to obtain the MIPAS2D database with atmospheric fields of pressure, temperature and volume mixing ratio of MIPAS main targets H2O, O3, HNO3, CH4, N2O, and NO2. The database covers both the MIPAS nominal observation mode measured at Full Resolution (FR) from July 2002 to March 2004 and the nominal observation mode of the new configuration, measured at Optimized Resolution (OR) and introduced in 2005. Further to the main targets, minor species N2O5, ClONO2, COF2, CFC-11, and CFC-12 for the FR mission only have been included in MIPAS2D to enhance its applicability in studies of stratospheric chemistry. The database is continuously updated with the analysis of the ongoing measurements that are planned to last until the end of 2013. The GMTR algorithm is operated on a fixed vertical grid coincident with the tangent altitudes of the FR nominal mode, spanning the altitude range from 6 to 68 km. In the horizontal domain, FR measurements are retrieved on both the observational grid and an equispaced 5 latitudinal-degrees grid which is made possible by the 2-dimensional retrieval algorithm. The analysis of MIPAS OR observations is operated on the same altitude-latitude fixed retrieval grid used for the FR measurements. This choice provides a homogeneous database in altitude and latitude, over the whole globe, covering to date about seven years of measurements. The equispaced latitudinal grid provides a new and convenient layout for the much needed synergetic studies of data from various instrumental and modeling sources. MIPAS2D is available to the scientific community through the two web sites http://www.mbf.fci.unibo.it/mipas2d.html, and http://www.isac.cnr.it/~rss/mipas2d.htm.

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Cross Sensor Simulation of Tomographic SAR Stacks

Remote Sensing ◽

10.3390/rs11182099 ◽

2019 ◽

Vol 11 (18) ◽

pp. 2099 ◽

Cited By ~ 1

Author(s):

Mauro Mariotti d’Alessandro ◽

Stefano Tebaldini

Keyword(s):

European Space Agency ◽

Three Dimensional ◽

Original Data ◽

Central Frequency ◽

Tropical Regions ◽

Space Agency ◽

Simulated System ◽

Good Proxy ◽

The Relationship ◽

Resolution Cell

This paper presents an algorithm for simulating tomographic synthetic aperture radar (SAR) data based on another stack actually gathered by a real acquisition system. Through the procedure here proposed, the simulated system can be evaluated according to its capability to image complex natural media rather than reference point targets. This feature is particularly important whenever the biophysical properties of the target of interest must be preserved and cannot be easily modeled. The system to be simulated may be different from the original one concerning resolution, off-nadir angles, bandwidth and central frequency. The algorithm here proposed handles these differences by properly taking into account the wavenumbers of the target illuminated by the real survey and requested by the simulated one. The complex images constituting the synthetic stack are associated with the effective vertical interferometric wavenumber peculiar of the geometry to be simulated, regardless of the original data. Furthermore, the three-dimensional resolution cell of the simulated tomographic system is consistent with the simulated geometry concerning size and spatial orientation. These two latter features cannot be guaranteed by simply filtering the original stack. The simulator here proposed has been used to simulate the tomographic stack expected from the forthcoming European Space Agency (ESA) BIOMASS mission. The relationship between baseline distribution and 3D focusing capability was explored; special attention has been paid to the robustness of tomographic power at being a good proxy for the above ground biomass in tropical regions.

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Theoretical uncertainties for global satellite-derived burned area estimates

Biogeosciences ◽

10.5194/bg-16-3147-2019 ◽

2019 ◽

Vol 16 (16) ◽

pp. 3147-3164 ◽

Cited By ~ 4

Author(s):

James Brennan ◽

Jose L. Gómez-Dans ◽

Mathias Disney ◽

Philip Lewis

Keyword(s):

European Space Agency ◽

Quantitative Information ◽

Burned Area ◽

Spatially Explicit ◽

Space Agency ◽

Uncertainty Estimates ◽

Moderate Resolution ◽

Resolution Imaging ◽

Moderate Resolution Imaging Spectroradiometer ◽

Area Product

Abstract. Quantitative information on the error properties of global satellite-derived burned area (BA) products is essential for evaluating the quality of these products, e.g. against modelled BA estimates. We estimate theoretical uncertainties for three widely used global satellite-derived BA products using a multiplicative triple collocation error model. The approach provides spatially unique uncertainties at 1∘ for the Moderate Resolution Imaging Spectroradiometer (MODIS) Collection 6 burned area product (MCD64), the MODIS Collection 5.1 (MCD45) product, and the European Space Agency (ESA) Climate Change Initiative Fire product version 5.0 (FireCCI50) for 2001–2013. The uncertainties on mean global burned area for three products are 3.76±0.15×106 km2 for MCD64, 3.70±0.17×106 km2 for FireCCI50, and 3.31±0.18×106 km2 for MCD45. These correspond to relative uncertainties of 4 %–5.5 % and also indicate previous uncertainty estimates to be underestimated. Relative uncertainties are 8 %–10 % in Africa and Australia, for example, and larger in regions with less annual burned area. The method provides uncertainties that are likely to be more consistent with modelling and data analysis studies due to their spatially explicit properties. These properties are also intended to allow spatially explicit validation of current burned area products.

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Land Cover Changes in Ghana over the Past 24 Years

Sustainability ◽

10.3390/su13094951 ◽

2021 ◽

Vol 13 (9) ◽

pp. 4951

Author(s):

Peter A. Y. Ampim ◽

Michael Ogbe ◽

Eric Obeng ◽

Edwin K. Akley ◽

Dilys S. MacCarthy

Keyword(s):

Land Cover ◽

Agricultural Land ◽

European Space Agency ◽

Original Data ◽

Bare Area ◽

The Past ◽

Space Agency ◽

Land Cover Data ◽

Emerging Issues ◽

Wide Scale

Changes in land cover (LC) can lead to environmental challenges, but few studies have investigated LC changes at a country wide scale in Ghana. Tracking LC changes at such a scale overtime is relevant for devising solutions to emerging issues. This study examined LC changes in Ghana for the past almost two and half decades covering 1995–2019 to highlight significant changes and opportunities for sustainable development. The study used land cover data for six selected years (1995, 2000, 2005, 2010, 2015, and 2019) obtained from the European Space Agency. The data was analyzed using R, ArcGIS Pro and Microsoft Excel 365 ProPlus. The original data was reclassified into eight LC categories, namely: agriculture, bare area, built-up, forest, grassland, other vegetation, waterbody, and wetland. On average, the results revealed 0.7%, 131.7%, 23.3%, 46.9%, and 11.2% increases for agriculture, built-up, forest, waterbody, and wetland, respectively, across the nation. However, losses were observed for bare area (92.8%), grassland (51.1%), and other vegetation (41%) LCs overall. Notably, agricultural land use increased up to 2015 and decreased subsequently but this did not affect production of the major staple foods. These findings reveal the importance of LC monitoring and the need for strategic efforts to address the causes of undesirable change.

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On sampling uncertainty of satellite ozone profile measurements

Atmospheric Measurement Techniques ◽

10.5194/amt-7-1891-2014 ◽

2014 ◽

Vol 7 (6) ◽

pp. 1891-1900 ◽

Cited By ~ 18

Author(s):

V. F. Sofieva ◽

N. Kalakoski ◽

S.-M. Päivärinta ◽

J. Tamminen ◽

M. Laine ◽

...

Keyword(s):

Standard Deviation ◽

Transport Model ◽

European Space Agency ◽

Atmospheric Measurements ◽

Sampling Uncertainty ◽

Space Agency ◽

Ozone Profile ◽

Uncertainty Estimates ◽

Continuous Fields ◽

Satellite Instruments

Abstract. Satellite measurements sample continuous fields of atmospheric constituents at discrete locations and times. However, insufficient or inhomogeneous sampling, if not taken into account, can result in inaccurate average estimates and even induce spurious features. We propose to characterize the spatiotemporal inhomogeneity of atmospheric measurements by a measure, which is a linear combination of the asymmetry and entropy of a sampling distribution. It is shown that this measure is related to the so-called sampling uncertainty, which occurs due to non-uniform sampling patterns. We have estimated the sampling uncertainty of zonal mean ozone profiles for six limb-viewing satellite instruments participating in the European Space Agency Ozone Climate Change Initiative project using the high-resolution ozone field simulated with the FinROSE chemistry-transport model. It is shown that the sampling uncertainty for the instruments with coarse sampling is not negligible and can be as large as a few percent. It is found that the standard deviation of the sampling uncertainty in the monthly zonal mean data allows for a simple parameterization in terms of the product of the standard deviation of natural variations and the proposed inhomogeneity measure. The sampling uncertainty estimates improve the uncertainty quantification and can be used in comprehensive data analyses. The focus of this work is the vertical ozone distributions measured by limb-viewing satellite instruments, but the developed methods can also be applied to different satellite, ground-based and in situ measurements.

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The MIPAS2D database of MIPAS/ENVISAT measurements retrieved with a multi-target 2-dimensional tomographic approach

Atmospheric Measurement Techniques ◽

10.5194/amt-3-355-2010 ◽

2010 ◽

Vol 3 (2) ◽

pp. 355-374 ◽

Cited By ~ 36

Author(s):

B. M. Dinelli ◽

E. Arnone ◽

G. Brizzi ◽

M. Carlotti ◽

E. Castelli ◽

...

Keyword(s):

Web Sites ◽

Michelson Interferometer ◽

European Space Agency ◽

Retrieval Algorithm ◽

Satellite Measurements ◽

Full Resolution ◽

Space Agency ◽

Vertical Grid ◽

Nominal Mode ◽

Tomographic Approach

Abstract. We present a multi-year database of atmospheric fields of the upper troposphere, stratosphere and lower mesosphere retrieved from satellite measurements adopting a 2-dimensional tomographic approach. The full mission of the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) instrument, on board the European Space Agency ENVISAT satellite, is analyzed with the Geofit Multi-Target Retrieval (GMTR) system to obtain the MIPAS2D database with atmospheric fields of pressure, temperature and volume mixing ratio of MIPAS main targets H2O, O3, HNO3, CH4, N2O, and NO2. The database covers both the MIPAS nominal observation mode measured at Full Resolution (FR) from July 2002 to March 2004 and the nominal observation mode of the new configuration, measured at Optimized Resolution (OR) and introduced in 2005. Further to the main targets, minor species N2O5, ClONO2, COF2, CFC-11, and CFC-12 for the FR mission only have been included in MIPAS2D to enhance its applicability in studies of stratospheric chemistry. The database is continuously updated with the analysis of the ongoing measurements that are planned to last until the end of 2013 and extended to other targets. The GMTR algorithm is operated on a fixed vertical grid coincident with the tangent altitudes of the FR nominal mode, spanning the altitude range from 6 to 68 km. In the horizontal domain, FR measurements are retrieved on both the observational grid and an equispaced 5 latitudinal-degrees grid which is made possible by the 2-dimensional retrieval algorithm. The analysis of MIPAS OR observations is operated on the same altitude-latitude fixed retrieval grid used for the FR measurements. This choice provides a database with a homogeneous altitude and latitude grid, over the whole globe, covering to date about seven years of measurements. The equispaced latitude grid provides a new and convenient layout for the much needed synergetic studies of data from various instrumental and modeling sources. MIPAS2D is available to the scientific community through the two web sites http://www.mbf.fci.unibo.it/mipas2d.html, and http://www.isac.cnr.it/~rss/mipas2d.htm

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Experimental Validation and Assimilation of Aeolus Wind Observations

10.5194/egusphere-egu2020-18186 ◽

2020 ◽

Author(s):

Anne Martin ◽

Alexander Geiss ◽

Alexander Cress ◽

Martin Weissmann

Keyword(s):

Experimental Validation ◽

European Space Agency ◽

Doppler Frequency ◽

Random Errors ◽

Space Agency ◽

Vertical Range ◽

Explorer Mission ◽

Global Coverage ◽

Wind Lidar ◽

Wind Profiles

The earth explorer mission Aeolus from the European Space Agency for the first time worldwide opens up the possibility to directly observe Earths&#8217; wind profiles from space. Aeolus carries a Doppler wind lidar operating at 335 nm which measures the Doppler frequency shift of backscattered laser light from air molecules and particles up to 30 km accumulated in 0.25 - 2 km vertical range bins. It&#8217;s expected that such global coverage of wind profiles helps to fill a gap in the global observing system.As part of the German initiative EVAA (Experimental Validation and Assimilation of Aeolus observations) validation and monitoring activities for Aeolus are performed to determine and understand observation systematic and random errors. Independent ground-based measurements from radiosondes and tropospheric radar wind profilers are used as reference for the evaluation of Aeolus winds. In addition monitoring results from the global model ICON from the German Weather Service (DWD) are used to examine the results and investigate bias dependencies. An accurate understanding of the systematic errors of Aeolus wind observations is necessary for data assimilation processes. First impact experiments with an established bias correction for Aeolus wind data were run at DWD showing encouraging results for forecast improvements in upper tropospheric and lower stratospheric tropics and southern hemisphere.

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