The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform

Wang Shi-gong - One of the best experts on this subject based on the ideXlab platform.

  • Research on Statistical Forecast of Haze in Winter in Lanzhou City
    Journal of Desert Research, 2011
    Co-Authors: Wang Shi-gong
    Abstract:

    Haze is a kind of weather phenomenon when dust,smoke and other dry particles obscure the clarity of sky,and its occurrence is caused not only by air pollution but also by weather conditions.The authors first analyzed the relationship between air visibility and pollutant concentration,and then established the statistical forest model for winter haze in Lanzhou City by simplifying the equation of air pollutant diffusing.The effects of Meteorological Element,air pollution and visibility were all taken into consideration in this model,so its physical foundation may be more believable than pure statistical models.The relationship between haze and weather conditions in Lanzhou City was analyzed by use of the visibility data,surface and lower layer Meteorological Element from the Lanzhou Meteorological Station,and the T213 numerical prediction products and the weather map during 2003-2008.The results showed that the reduced air pressure field are favorable for the occurrence of haze in Lanzhou.Finally,a 24-hour haze forecast equation for the Lanzhou City was derived from stepwise regression.This equation was verified by the observation data in 2009,which proved the forecasting results are credible.

  • Research on Variations of Climate and Its Aridity in the Valley of Yellow River and Huangshui River within Qinghai Province
    Journal of Desert Research, 2006
    Co-Authors: Zhao Yan-ning, Wang Shi-gong, Shi Xing-he, Qin Ning-sheng, Wang Qing-chun, Feng Shu-qing
    Abstract:

    Using the data of temperature,precipitation,ground evaporation from 11 Meteorological stations in the valley of the Yellow River and the Huangshui River within Qinghai Province(shortened for Hehuang valley) from 1961 to 2002,we analyzed the characters of Meteorological Element change and aridity variety.The result is as follows: The season average temperature of Hehuang valley in 1990's was 0.3~0.5℃ higher than that in 1960's and 1980's;Temperature increase was obviously in winter.The annual average precipitation in 1990's was 17.2 mm less than that in 1960's.The surface evaporation increase in 1980's to 1990's was more than that in 1960's to 1970's.The decrease of precipitation in spring and autumn since 1990 made the drought frequency increase in autumn and spring and the valley runoff reduce.

Feng Shu-qing - One of the best experts on this subject based on the ideXlab platform.

  • Research on Variations of Climate and Its Aridity in the Valley of Yellow River and Huangshui River within Qinghai Province
    Journal of Desert Research, 2006
    Co-Authors: Zhao Yan-ning, Wang Shi-gong, Shi Xing-he, Qin Ning-sheng, Wang Qing-chun, Feng Shu-qing
    Abstract:

    Using the data of temperature,precipitation,ground evaporation from 11 Meteorological stations in the valley of the Yellow River and the Huangshui River within Qinghai Province(shortened for Hehuang valley) from 1961 to 2002,we analyzed the characters of Meteorological Element change and aridity variety.The result is as follows: The season average temperature of Hehuang valley in 1990's was 0.3~0.5℃ higher than that in 1960's and 1980's;Temperature increase was obviously in winter.The annual average precipitation in 1990's was 17.2 mm less than that in 1960's.The surface evaporation increase in 1980's to 1990's was more than that in 1960's to 1970's.The decrease of precipitation in spring and autumn since 1990 made the drought frequency increase in autumn and spring and the valley runoff reduce.

Liu Xiao-yun - One of the best experts on this subject based on the ideXlab platform.

  • Variations of Surface Meteorological Element during Twice Sandstorms Passing Jiuquan on March 28 and July 12 of 2004
    Journal of Desert Research, 2007
    Co-Authors: Liu Xiao-yun
    Abstract:

    Based on the per minute surface Meteorological Element data of the twice sandstorms cases recorded by sandstorm automatic observation system of Jiuquan base station on March 28 and on July 12 of 2004,the micro Meteorological Element change characteristics were analyzed.The result indicated that: ①The surface humidity and barometric pressure were both quite low before sandstorms.Surface pressure increased suddenly in the beginning course of the twice sandstorms,then maintained a period of relatively steady states.But the relatively steady period was longer in the spring sandstorm case than that in winter sandstorm case.The surface pressure largely increased once again before sandstorms nearly finished.②The surface air temperature was high before sandstorms happened,but decreased quickly at the end of the course.In the spring sandstorm period,the 0 cm depth earth temperature and surface air temperature change tendencies were quite consistent.But in summer not only the 0 cm depth earth temperature but the 5 cm depth earth temperature variation was consistent with surface air temperature change tendency.③Owning to the difference of the surface characters in different seasons,the horizontal visibility of summer case was bad than the spring courses,although the horizontal wind speed of the spring occurs was obviously bigger than that of the summer sandstorms.

Jun Zhang - One of the best experts on this subject based on the ideXlab platform.

  • application of lstm for short term fog forecasting based on Meteorological Elements
    Neurocomputing, 2020
    Co-Authors: Kaichao Miao, Hui Lu, Peng Chen, Bing Wang, Jun Zhang
    Abstract:

    Abstract Fog is the main weather phenomenon that causes low visibility, which makes traffic and outdoor work extremely dangerous. In this paper, we propose a novel LSTM framework for short-term fog forecasting. The proposed network framework consists of an LSTM network and fully connected layer. In order to make the proposed LSTM framework work, the Meteorological Element observation data returned hourly is transferred into time series data. Based on these time series data, four datasets are created for short-term fog forecasting. In order to evaluate the proposed LSTM framework, we conduct comprehensive experiments with different machine learning algorithms. Compared with K-Nearest Neighbor (KNN), AdaBoost and convolutional neural network (CNN) algorithms, the experimental results show that the proposed LSTM framework achieves best prediction performance in four evaluation criteria. Especially in TS-Score, the proposed LSTM framework achieve 1.1%, 11%, 3%, and 11% higher performance than the best traditional machine learning algorithm.

Zhao Yan-ning - One of the best experts on this subject based on the ideXlab platform.

  • Research on Variations of Climate and Its Aridity in the Valley of Yellow River and Huangshui River within Qinghai Province
    Journal of Desert Research, 2006
    Co-Authors: Zhao Yan-ning, Wang Shi-gong, Shi Xing-he, Qin Ning-sheng, Wang Qing-chun, Feng Shu-qing
    Abstract:

    Using the data of temperature,precipitation,ground evaporation from 11 Meteorological stations in the valley of the Yellow River and the Huangshui River within Qinghai Province(shortened for Hehuang valley) from 1961 to 2002,we analyzed the characters of Meteorological Element change and aridity variety.The result is as follows: The season average temperature of Hehuang valley in 1990's was 0.3~0.5℃ higher than that in 1960's and 1980's;Temperature increase was obviously in winter.The annual average precipitation in 1990's was 17.2 mm less than that in 1960's.The surface evaporation increase in 1980's to 1990's was more than that in 1960's to 1970's.The decrease of precipitation in spring and autumn since 1990 made the drought frequency increase in autumn and spring and the valley runoff reduce.