| 1. |
- Blas, M., et al.
(author)
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Temporal and spatial variations of fog in the Western Sudety Mts., Poland
- 2002
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In: Atmospheric research. - 0169-8095 .- 1873-2895. ; 64:04-jan, s. 19-28
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Journal article (peer-reviewed)abstract
- The ridges of the Western Sudety are well exposed to the humid maritime air masses that are mainly associated with westerly atmospheric circulation. Fog is the most frequently observed atmospheric phenomenon, being present on average 45% of the time, with 250-300 days with fog per year. This study on temporal variation of fog in both daily and annual cycles is based on 30 years of measurements (1961 - 1990) made on Mt. Szrcnica at 1362 m a.s.l. Based on the data from 51 meteorological stations and the results of fog deposition field measurements, a digital model of fog frequency in the Western Sudety was prepared using a Geographic Information System. The model shows that altitude is not the only important factor controlling fog frequency. Such parameters as slope aspect and position of a particular site in relation to local and regional morphology are also of crucial importance.
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| 2. |
- Emde, Claudia, et al.
(author)
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The effect of cirrus clouds on microwave limb radiances
- 2004
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In: Atmospheric research. - : Elsevier BV. - 0169-8095 .- 1873-2895. ; 72:1-4, s. 383-401
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Journal article (peer-reviewed)abstract
- This study presents and analyses the first simulations of microwave limb radiances with clouds. They are computed using the 1D unpolarized version of the Atmospheric Radiative Transfer System (ARTS). The study is meant to set a theoretical foundation for using microwave limb measurements for cloud monitoring. Information about clouds is required for the validation of climate models.Limb spectra are generated for the frequency bands of the Millimeter wave Acquisitions for Stratosphere/Troposphere Exchange Research (MASTER) instrument. For these simulations, the radiative transfer equation is solved using the Discrete Ordinate ITerative (DOIT) method, which is briefly described. Single scattering properties for the cloud particles are calculated using the T-matrix method.The impact of various cloud parameters is investigated. Simulated brightness temperatures most strongly depend on particle size, ice mass content and cloud altitude. The impact of particle shape is much smaller, but still significant. Increasing the ice mass content has a similar effect as increasing the particle size; this complicates the prediction of the impact of clouds on microwave radiances without exact knowledge of these cloud parameters.
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