Yes / In this paper, local meteorological data for a period of 35 years (from 1979 to 2013) from Kuujuaq station have been used to calculate the surface refractivity, N and to estimate the vertical refractivity gradient, dN1, in the lowest atmospheric layer above the ground. Monthly and yearly variations of the mean of N and dN1 are provided. The values obtained are compared with the corresponding values from the ITU maps. The long-term trend of the surface refractivity is also investigated. The data demonstrate that the indices N and dN1 are subject to an evolution which may have significance in the context of climate change (CC). Monthly means of N show an increasing departure from ITU-R values since 1990. Yearly mean values of the dN1 show a progressive decrease over the period of study. Seasonal means of dN1 show a decrease over time, especially for summer. Such a trend may increase the occurrence of super-refraction. However, currently available ITU-R recommendations for microwave link design assume a stationary climate, so there is a need for a new modelling approach.
Identifer | oai:union.ndltd.org:BRADFORD/oai:bradscholars.brad.ac.uk:10454/17153 |
Date | 02 July 2019 |
Creators | Bettouche, Y., Kouki, A., Agba, B., Obeidat, Huthaifa A.N., Alhassan, H., Rodriguez, Jonathan, Abd-Alhameed, Raed, Jones, Steven M.R. |
Source Sets | Bradford Scholars |
Language | English |
Detected Language | English |
Type | Article, Published version |
Rights | ©2019 American Geophysical Union. All Rights Reserved. Reproduced in accordance with the publisher's self-archiving policy., Unspecified |
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