Time series inversion of spectra from ground-based radiometers
Retrieving time series of atmospheric constituents from ground-based spectrometers often requires different temporal averaging depending on the altitude region in focus. This can lead to several datasets existing for one instrument, which complicates validation and comparisons between instruments. T...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2013-07-01
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| Series: | Atmospheric Measurement Techniques |
| Online Access: | http://www.atmos-meas-tech.net/6/1597/2013/amt-6-1597-2013.pdf |
| _version_ | 1819206951641284608 |
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| author | O. M. Christensen P. Eriksson |
| author_facet | O. M. Christensen P. Eriksson |
| author_sort | O. M. Christensen |
| collection | DOAJ |
| description | Retrieving time series of atmospheric constituents from ground-based spectrometers often requires different temporal averaging depending on the altitude region in focus. This can lead to several datasets existing for one instrument, which complicates validation and comparisons between instruments. This paper puts forth a possible solution by incorporating the temporal domain into the maximum a posteriori (MAP) retrieval algorithm. The state vector is increased to include measurements spanning a time period, and the temporal correlations between the true atmospheric states are explicitly specified in the a priori uncertainty matrix. This allows the MAP method to effectively select the best temporal smoothing for each altitude, removing the need for several datasets to cover different altitudes. <br><br> The method is compared to traditional averaging of spectra using a simulated retrieval of water vapour in the mesosphere. The simulations show that the method offers a significant advantage compared to the traditional method, extending the sensitivity an additional 10 km upwards without reducing the temporal resolution at lower altitudes. The method is also tested on the Onsala Space Observatory (OSO) water vapour microwave radiometer confirming the advantages found in the simulation. Additionally, it is shown how the method can interpolate data in time and provide diagnostic values to evaluate the interpolated data. |
| first_indexed | 2024-12-23T05:15:45Z |
| format | Article |
| id | doaj.art-aeff12b405154e06957edb2113206fdd |
| institution | Directory Open Access Journal |
| issn | 1867-1381 1867-8548 |
| language | English |
| last_indexed | 2024-12-23T05:15:45Z |
| publishDate | 2013-07-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Measurement Techniques |
| spelling | doaj.art-aeff12b405154e06957edb2113206fdd2022-12-21T17:58:49ZengCopernicus PublicationsAtmospheric Measurement Techniques1867-13811867-85482013-07-01671597160910.5194/amt-6-1597-2013Time series inversion of spectra from ground-based radiometersO. M. ChristensenP. ErikssonRetrieving time series of atmospheric constituents from ground-based spectrometers often requires different temporal averaging depending on the altitude region in focus. This can lead to several datasets existing for one instrument, which complicates validation and comparisons between instruments. This paper puts forth a possible solution by incorporating the temporal domain into the maximum a posteriori (MAP) retrieval algorithm. The state vector is increased to include measurements spanning a time period, and the temporal correlations between the true atmospheric states are explicitly specified in the a priori uncertainty matrix. This allows the MAP method to effectively select the best temporal smoothing for each altitude, removing the need for several datasets to cover different altitudes. <br><br> The method is compared to traditional averaging of spectra using a simulated retrieval of water vapour in the mesosphere. The simulations show that the method offers a significant advantage compared to the traditional method, extending the sensitivity an additional 10 km upwards without reducing the temporal resolution at lower altitudes. The method is also tested on the Onsala Space Observatory (OSO) water vapour microwave radiometer confirming the advantages found in the simulation. Additionally, it is shown how the method can interpolate data in time and provide diagnostic values to evaluate the interpolated data.http://www.atmos-meas-tech.net/6/1597/2013/amt-6-1597-2013.pdf |
| spellingShingle | O. M. Christensen P. Eriksson Time series inversion of spectra from ground-based radiometers Atmospheric Measurement Techniques |
| title | Time series inversion of spectra from ground-based radiometers |
| title_full | Time series inversion of spectra from ground-based radiometers |
| title_fullStr | Time series inversion of spectra from ground-based radiometers |
| title_full_unstemmed | Time series inversion of spectra from ground-based radiometers |
| title_short | Time series inversion of spectra from ground-based radiometers |
| title_sort | time series inversion of spectra from ground based radiometers |
| url | http://www.atmos-meas-tech.net/6/1597/2013/amt-6-1597-2013.pdf |
| work_keys_str_mv | AT omchristensen timeseriesinversionofspectrafromgroundbasedradiometers AT periksson timeseriesinversionofspectrafromgroundbasedradiometers |