Validation of brightness and physical temperature from two scanning microwave radiometers in the 60 GHz O<sub>2</sub> band using radiosonde measurements
In this paper, we address the assessment of the tropospheric performance of a new temperature radiometer (TEMPERA) at 60 GHz. With this goal, an intercomparison campaign was carried out at the aerological station of MeteoSwiss in Payerne (Switzerland). The brightness temperature and the tropospheric...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2016-09-01
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| Series: | Atmospheric Measurement Techniques |
| Online Access: | http://www.atmos-meas-tech.net/9/4587/2016/amt-9-4587-2016.pdf |
| _version_ | 1828793785565315072 |
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| author | F. Navas-Guzmán N. Kämpfer A. Haefele |
| author_facet | F. Navas-Guzmán N. Kämpfer A. Haefele |
| author_sort | F. Navas-Guzmán |
| collection | DOAJ |
| description | In this paper, we address the assessment of the tropospheric performance of a
new temperature radiometer (TEMPERA) at 60 GHz. With this goal, an
intercomparison campaign was carried out at the aerological station of
MeteoSwiss in Payerne (Switzerland). The brightness temperature and the
tropospheric temperature were assessed by means of a comparison with
simultaneous and collocated radiosondes that are launched twice a day at
this station. In addition, the TEMPERA performances are compared with the
ones from a commercial microwave radiometer (HATPRO), which has some different
instrumental characteristics and uses a different inversion algorithm.
Brightness temperatures from both radiometers were compared with the ones
simulated using a radiative transfer model and atmospheric profiles from
radiosondes. A total of 532 cases were analyzed under all weather conditions
and evidenced larger brightness temperature deviations between the two
radiometers and the radiosondes for the most transparent channels.
Two different retrievals for the TEMPERA radiometer were implemented in order
to evaluate the effect of the different channels on the temperature
retrievals. The comparison with radiosondes evidenced better results very
similar to the ones from HATPRO, when the eight more opaque channels were used.
The study shows the good performance of TEMPERA to retrieve temperature
profiles in the troposphere. The inversion method of TEMPERA is based on the
optimal estimation method. The main advantage of this algorithm is that there is no necessity for
radiosonde information to achieve good results in contrast to conventional
methods as neural networks or lineal regression. Finally, an assessment of the effect of instrumental characteristics as the
filter response and the antenna pattern on the brightness temperature showed
that they can have an important impact on the most transparent channels. |
| first_indexed | 2024-12-12T03:33:45Z |
| format | Article |
| id | doaj.art-a3a04f3282694e74a60c7cd4af4b16b2 |
| institution | Directory Open Access Journal |
| issn | 1867-1381 1867-8548 |
| language | English |
| last_indexed | 2024-12-12T03:33:45Z |
| publishDate | 2016-09-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Measurement Techniques |
| spelling | doaj.art-a3a04f3282694e74a60c7cd4af4b16b22022-12-22T00:39:52ZengCopernicus PublicationsAtmospheric Measurement Techniques1867-13811867-85482016-09-01994587460010.5194/amt-9-4587-2016Validation of brightness and physical temperature from two scanning microwave radiometers in the 60 GHz O<sub>2</sub> band using radiosonde measurementsF. Navas-Guzmán0N. Kämpfer1A. Haefele2Institute of Applied Physics (IAP), University of Bern, Bern, SwitzerlandInstitute of Applied Physics (IAP), University of Bern, Bern, SwitzerlandFederal Office of Meteorology and Climatology MeteoSwiss, Payerne, SwitzerlandIn this paper, we address the assessment of the tropospheric performance of a new temperature radiometer (TEMPERA) at 60 GHz. With this goal, an intercomparison campaign was carried out at the aerological station of MeteoSwiss in Payerne (Switzerland). The brightness temperature and the tropospheric temperature were assessed by means of a comparison with simultaneous and collocated radiosondes that are launched twice a day at this station. In addition, the TEMPERA performances are compared with the ones from a commercial microwave radiometer (HATPRO), which has some different instrumental characteristics and uses a different inversion algorithm. Brightness temperatures from both radiometers were compared with the ones simulated using a radiative transfer model and atmospheric profiles from radiosondes. A total of 532 cases were analyzed under all weather conditions and evidenced larger brightness temperature deviations between the two radiometers and the radiosondes for the most transparent channels. Two different retrievals for the TEMPERA radiometer were implemented in order to evaluate the effect of the different channels on the temperature retrievals. The comparison with radiosondes evidenced better results very similar to the ones from HATPRO, when the eight more opaque channels were used. The study shows the good performance of TEMPERA to retrieve temperature profiles in the troposphere. The inversion method of TEMPERA is based on the optimal estimation method. The main advantage of this algorithm is that there is no necessity for radiosonde information to achieve good results in contrast to conventional methods as neural networks or lineal regression. Finally, an assessment of the effect of instrumental characteristics as the filter response and the antenna pattern on the brightness temperature showed that they can have an important impact on the most transparent channels.http://www.atmos-meas-tech.net/9/4587/2016/amt-9-4587-2016.pdf |
| spellingShingle | F. Navas-Guzmán N. Kämpfer A. Haefele Validation of brightness and physical temperature from two scanning microwave radiometers in the 60 GHz O<sub>2</sub> band using radiosonde measurements Atmospheric Measurement Techniques |
| title | Validation of brightness and physical temperature from two scanning
microwave radiometers in the 60 GHz O<sub>2</sub> band using radiosonde measurements |
| title_full | Validation of brightness and physical temperature from two scanning
microwave radiometers in the 60 GHz O<sub>2</sub> band using radiosonde measurements |
| title_fullStr | Validation of brightness and physical temperature from two scanning
microwave radiometers in the 60 GHz O<sub>2</sub> band using radiosonde measurements |
| title_full_unstemmed | Validation of brightness and physical temperature from two scanning
microwave radiometers in the 60 GHz O<sub>2</sub> band using radiosonde measurements |
| title_short | Validation of brightness and physical temperature from two scanning
microwave radiometers in the 60 GHz O<sub>2</sub> band using radiosonde measurements |
| title_sort | validation of brightness and physical temperature from two scanning microwave radiometers in the 60 ghz o sub 2 sub band using radiosonde measurements |
| url | http://www.atmos-meas-tech.net/9/4587/2016/amt-9-4587-2016.pdf |
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