A Ground Observation Based Climatology of Winter Fog: Study over the Indo-Gangetic Plains, India
Commenced in January 2007
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A Ground Observation Based Climatology of Winter Fog: Study over the Indo-Gangetic Plains, India

Authors: Sanjay Kumar Srivastava, Anu Rani Sharma, Kamna Sachdeva

Abstract:

Every year, fog formation over the Indo-Gangetic Plains (IGPs) of Indian region during the winter months of December and January is believed to create numerous hazards, inconvenience, and economic loss to the inhabitants of this densely populated region of Indian subcontinent. The aim of the paper is to analyze the spatial and temporal variability of winter fog over IGPs. Long term ground observations of visibility and other meteorological parameters (1971-2010) have been analyzed to understand the formation of fog phenomena and its relevance during the peak winter months of January and December over IGP of India. In order to examine the temporal variability, time series and trend analysis were carried out by using the Mann-Kendall Statistical test. Trend analysis performed by using the Mann-Kendall test, accepts the alternate hypothesis with 95% confidence level indicating that there exists a trend. Kendall tau’s statistics showed that there exists a positive correlation between time series and fog frequency. Further, the Theil and Sen’s median slope estimate showed that the magnitude of trend is positive. Magnitude is higher during January compared to December for the entire IGP except in December when it is high over the western IGP. Decade wise time series analysis revealed that there has been continuous increase in fog days. The net overall increase of 99 % was observed over IGP in last four decades. Diurnal variability and average daily persistence were computed by using descriptive statistical techniques. Geo-statistical analysis of fog was carried out to understand the spatial variability of fog. Geo-statistical analysis of fog revealed that IGP is a high fog prone zone with fog occurrence frequency of more than 66% days during the study period. Diurnal variability indicates the peak occurrence of fog is between 06:00 and 10:00 local time and average daily fog persistence extends to 5 to 7 hours during the peak winter season. The results would offer a new perspective to take proactive measures in reducing the irreparable damage that could be caused due to changing trends of fog.

Keywords: Fog, climatology, Mann-Kendall test, trend analysis, spatial variability, temporal variability, visibility.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1125465

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References:


[1] Gong F U, Guo J, Xie SP, Duan Y, Zhong M. 2006. Analysis and high resolution modeling of a dense fog over Yellow sea, Atmospheric Research. 81;293-303.
[2] Gultepe I, Tardif R, Michaelides S.C, Cermak J, Bott A, Bendix J, Müller M. D, Pagowski M, Hansen B., Ellrod G, Jacobs W, Toth G, Cober S. G. 2007. Fog research: A review of past achievements and Future perspectives, Pure and Applied Geophysics., 164: 1121-1159.
[3] Meyer, M.B. and Lala, G.G. 1990, Climatological aspects of radiation fog occurrence at Albany, New York, J. Climate 3, 577–586.
[4] Lewis JM, koracin D, Redmond KT.2004. Sea Fog Research in the United Kingdom and United Sates; A Historical Essay Including Outlook. Bull. Meir, Meteor. Soc., 85: 395-408.
[5] Badrinath KVS, Kharol SK, Sharma AR, Roy PS .2009, Fog over Indo-Gangetic Plains - A study using multi-satellite data and ground observation. 3 (2):185-195.
[6] Bhushan B, Trivedi H K N, Bhatia R C, Dube R K, Giri R K, and Negi R .2003. “On the persistence of fog over northern parts of India”. Museum., 54: 851-860.
[7] Singh J, and Kant, S.2006. Radiation fog over north India during winter from 1989-2004. Mausam. 57, 2: 271-290.
[8] SinghJ, GiriR K, and Kant S.2007. “Radiation fog viewed by INSAT-1 D and Kalpana Geo Stationary satellite”. Mausam.58, 2: 251-260.
[9] Jennamani R K., 2007 Analysis of large scale dense fog over Indo-Gangetic region from satellite pictures, 2007.
[10] Bhowmik R, SudS, K, and Singh C.2004. “Forecasting fog over Delhi - An objective method”. Museum. 55: 313-322.
[11] Yue S, Pilon P, Cavadias G. Power of the Mann Kendall and Spearman’s rho test for detecting monotonic trends in hydrological series. J. Hydrol., 259: 254-271.
[12] Narayanan P, Basistha A Sarkar S, Sachdeva K, 2013. Trend analysis and ARIMA modeling of pre-monsoon rainfall data for western India, Comptes Rendius Geo-Science.345)1): 22-27.
[13] Bayazit M et al. 2007.To prewhiten or not to prewhiten in trend analysis. Hydrol. Sci. J., 52 (4): 611-624.
[14] Box GE. P, Jenkins G M, and Reinsel G C.2007.Time Series Analysis: forecasting and control third ed. Pearson Education., 8-12.
[15] Chattopadhyay S, Chattopadhyay G.2010Univariate modelling of summer-monsoon rainfall time series: comparison between ARIMA and ARNN. CR Geo-science 342. 100-107.
[16] Martin DE.1972. Climatic presentations for short-range forecasting based on event occurrences profile, J.Appl. Meteor,11,1212-1223.