Characterization of downwelling radiance measured from a ground-based microwave radiometer using numerical weather prediction model data
The ground-based microwave sounding radiometers installed at nine weather stations of Korea Meteorological Administration alongside with the wind profilers have been operating for more than 4 years. Here we apply a process to assess the characteristics of the observation data by comparing the measur...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2016-01-01
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| Series: | Atmospheric Measurement Techniques |
| Online Access: | http://www.atmos-meas-tech.net/9/281/2016/amt-9-281-2016.pdf |
| _version_ | 1818193274345619456 |
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| author | M.-H. Ahn H. Y. Won D. Han Y.-H. Kim J.-C. Ha |
| author_facet | M.-H. Ahn H. Y. Won D. Han Y.-H. Kim J.-C. Ha |
| author_sort | M.-H. Ahn |
| collection | DOAJ |
| description | The ground-based microwave sounding radiometers installed at nine weather
stations of Korea Meteorological Administration alongside with the wind
profilers have been operating for more than 4 years. Here we apply a process
to assess the characteristics of the observation data by comparing the
measured brightness temperature (<i>T</i><sub>b</sub>) with reference data. For the current study,
the reference data are prepared by the radiative transfer simulation with
the temperature and humidity profiles from the numerical weather prediction
model instead of the conventional radiosonde data. Based on the 3 years
of data, from 2010 to 2012, we were able to characterize the effects of the
absolute calibration on the quality of the measured <i>T</i><sub>b</sub>. We also showed that
when clouds are present the comparison with the model has a high variability
due to presence of cloud liquid water therefore making cloudy data not
suitable for assessment of the radiometer's performance. Finally we showed
that differences between modeled and measured brightness temperatures are
unlikely due to a shift in the selection of the center frequency but more
likely due to spectroscopy issues in the wings of the 60 GHz absorption
band. With a proper consideration of data affected by these two effects, it
is shown that there is an excellent agreement between the measured and
simulated <i>T</i><sub>b</sub>. The regression coefficients are better than 0.97 along with the
bias value of better than 1.0 K except for the 52.28 GHz channel which shows
a rather large bias and variability of −2.6 and 1.8 K, respectively. |
| first_indexed | 2024-12-12T00:43:47Z |
| format | Article |
| id | doaj.art-c27320ade9084f38bcdee53ba08fc0d4 |
| institution | Directory Open Access Journal |
| issn | 1867-1381 1867-8548 |
| language | English |
| last_indexed | 2024-12-12T00:43:47Z |
| publishDate | 2016-01-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Measurement Techniques |
| spelling | doaj.art-c27320ade9084f38bcdee53ba08fc0d42022-12-22T00:44:10ZengCopernicus PublicationsAtmospheric Measurement Techniques1867-13811867-85482016-01-019128129310.5194/amt-9-281-2016Characterization of downwelling radiance measured from a ground-based microwave radiometer using numerical weather prediction model dataM.-H. Ahn0H. Y. Won1D. Han2Y.-H. Kim3J.-C. Ha4Department of Atmospheric Science and Engineering, Ewha Womans University, Ewha-Yeodae-Gil 52, Seodaemoon-Gu, Seoul, Republic of KoreaDepartment of Atmospheric Science and Engineering, Ewha Womans University, Ewha-Yeodae-Gil 52, Seodaemoon-Gu, Seoul, Republic of KoreaDepartment of Atmospheric Science and Engineering, Ewha Womans University, Ewha-Yeodae-Gil 52, Seodaemoon-Gu, Seoul, Republic of KoreaNational Institute of Meteorological Sciences, Korea Meteorological Administration, 33, Seohobuk-ro, Seogwipo Jeju-do, Republic of KoreaNational Institute of Meteorological Sciences, Korea Meteorological Administration, 33, Seohobuk-ro, Seogwipo Jeju-do, Republic of KoreaThe ground-based microwave sounding radiometers installed at nine weather stations of Korea Meteorological Administration alongside with the wind profilers have been operating for more than 4 years. Here we apply a process to assess the characteristics of the observation data by comparing the measured brightness temperature (<i>T</i><sub>b</sub>) with reference data. For the current study, the reference data are prepared by the radiative transfer simulation with the temperature and humidity profiles from the numerical weather prediction model instead of the conventional radiosonde data. Based on the 3 years of data, from 2010 to 2012, we were able to characterize the effects of the absolute calibration on the quality of the measured <i>T</i><sub>b</sub>. We also showed that when clouds are present the comparison with the model has a high variability due to presence of cloud liquid water therefore making cloudy data not suitable for assessment of the radiometer's performance. Finally we showed that differences between modeled and measured brightness temperatures are unlikely due to a shift in the selection of the center frequency but more likely due to spectroscopy issues in the wings of the 60 GHz absorption band. With a proper consideration of data affected by these two effects, it is shown that there is an excellent agreement between the measured and simulated <i>T</i><sub>b</sub>. The regression coefficients are better than 0.97 along with the bias value of better than 1.0 K except for the 52.28 GHz channel which shows a rather large bias and variability of −2.6 and 1.8 K, respectively.http://www.atmos-meas-tech.net/9/281/2016/amt-9-281-2016.pdf |
| spellingShingle | M.-H. Ahn H. Y. Won D. Han Y.-H. Kim J.-C. Ha Characterization of downwelling radiance measured from a ground-based microwave radiometer using numerical weather prediction model data Atmospheric Measurement Techniques |
| title | Characterization of downwelling radiance measured from a ground-based microwave radiometer using numerical weather prediction model data |
| title_full | Characterization of downwelling radiance measured from a ground-based microwave radiometer using numerical weather prediction model data |
| title_fullStr | Characterization of downwelling radiance measured from a ground-based microwave radiometer using numerical weather prediction model data |
| title_full_unstemmed | Characterization of downwelling radiance measured from a ground-based microwave radiometer using numerical weather prediction model data |
| title_short | Characterization of downwelling radiance measured from a ground-based microwave radiometer using numerical weather prediction model data |
| title_sort | characterization of downwelling radiance measured from a ground based microwave radiometer using numerical weather prediction model data |
| url | http://www.atmos-meas-tech.net/9/281/2016/amt-9-281-2016.pdf |
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