Based on the atmospheric horizontal visibility data from forty-seven observational stations along the eastern coast of China near the Taiwan Strait and simultaneous NOAA/AVHRR multichannel satellite data during Januar...Based on the atmospheric horizontal visibility data from forty-seven observational stations along the eastern coast of China near the Taiwan Strait and simultaneous NOAA/AVHRR multichannel satellite data during January 2001 to December 2002, the spectral characters associated with visibility were investigated. Successful retrieval of visibility from multichannel NOAA/AVHRR data was performed using the principal component regression （PCR） method. A sample of retrieved visibility distribution was discussed with a sea fog process. The correlation coefficient between the observed and retrieved visibility was about 0.82, which is far higher than the 99.9% confidence level by statistical test. The rate of successful retrieval is 94.98% of the 458 cases during 2001 2002. The error distribution showed that high visibilities were usually under-estimated and low visibilities were over-estimated and the relative error between the observed and retrieved visibilities was about 21.4%.展开更多
The Moderate Resolution Imaging Spectroradiometer(MODIS)satellite imagery,weather charts,objectively reanalyzed data,the observational data and station sounding data were analyzed to investigate a sea fog event occurr...The Moderate Resolution Imaging Spectroradiometer(MODIS)satellite imagery,weather charts,objectively reanalyzed data,the observational data and station sounding data were analyzed to investigate a sea fog event occurred over the Yellow and East China Seas on March 17,2014.The sounding profiles,weather situations and the related meteorological factors during the development and dissipation stages of this sea fog event were documented.Weather Research Forecast(WRF)model was applied to simulate this sea fog case.The simulated horizontal atmospheric visibility,cloud water,humidity,and vertical wind profile during the different stages of this fog event were analyzed.During the development stage of this sea fog,a southerly lower-jet with 16-18 ms-1,an inversion layer and a cold center over the Yellow Sea were detected.The relative humidity in the fog area was above 95%.The specific humidity over the East China Sea was higher than that over the Yellow Sea.Southerly was dominated in fog area.However,during the dissipation stage of this sea fog,westerly replaced the southerly and at the lower level,southerly jet disappeared.A dry air area formed over the Shandong Peninsula and moved eastwards.Moreover,the WRF modeling result showed that the simulated atmospheric horizontal visibility and cloud water were approximately consistent with the MODIS satellite imagery.Most of cloud water concentrated below 200-400 m,and the cloud water in the southern part of fog area extended to a higher height than the northern part.While both of air temperature and dew-point temperature were close to sea surface temperature.展开更多
基金This research is supported by the National High Technology Development Project （863） of China （Grant No. 2002AA639500） the Natural Science Foundation of Guangdong Province （Grant No. 032212）+1 种基金 National Basic Research Program of China （973 Program） （No. 2005CB422301） Program for New Century Excellent Talents in University （ NCET-05-0591 ）.
文摘Based on the atmospheric horizontal visibility data from forty-seven observational stations along the eastern coast of China near the Taiwan Strait and simultaneous NOAA/AVHRR multichannel satellite data during January 2001 to December 2002, the spectral characters associated with visibility were investigated. Successful retrieval of visibility from multichannel NOAA/AVHRR data was performed using the principal component regression （PCR） method. A sample of retrieved visibility distribution was discussed with a sea fog process. The correlation coefficient between the observed and retrieved visibility was about 0.82, which is far higher than the 99.9% confidence level by statistical test. The rate of successful retrieval is 94.98% of the 458 cases during 2001 2002. The error distribution showed that high visibilities were usually under-estimated and low visibilities were over-estimated and the relative error between the observed and retrieved visibilities was about 21.4%.
文摘The Moderate Resolution Imaging Spectroradiometer(MODIS)satellite imagery,weather charts,objectively reanalyzed data,the observational data and station sounding data were analyzed to investigate a sea fog event occurred over the Yellow and East China Seas on March 17,2014.The sounding profiles,weather situations and the related meteorological factors during the development and dissipation stages of this sea fog event were documented.Weather Research Forecast(WRF)model was applied to simulate this sea fog case.The simulated horizontal atmospheric visibility,cloud water,humidity,and vertical wind profile during the different stages of this fog event were analyzed.During the development stage of this sea fog,a southerly lower-jet with 16-18 ms-1,an inversion layer and a cold center over the Yellow Sea were detected.The relative humidity in the fog area was above 95%.The specific humidity over the East China Sea was higher than that over the Yellow Sea.Southerly was dominated in fog area.However,during the dissipation stage of this sea fog,westerly replaced the southerly and at the lower level,southerly jet disappeared.A dry air area formed over the Shandong Peninsula and moved eastwards.Moreover,the WRF modeling result showed that the simulated atmospheric horizontal visibility and cloud water were approximately consistent with the MODIS satellite imagery.Most of cloud water concentrated below 200-400 m,and the cloud water in the southern part of fog area extended to a higher height than the northern part.While both of air temperature and dew-point temperature were close to sea surface temperature.
