Authors: Zekâi Şen
Addresses: Engineering and Natural Sciences Faculty, Istanbul Medipol University, Kavacık, Istanbul, Turkey; Centre of Excellence for Climate Change Research (CECCR), Meteorology and Agriculture Department, Faculty of Arid Lands, King Abdulaziz University, Jeddah, Saudi Arabia
Abstract: This paper presents an innovative multi-cross trend (IMCT) approach based on the number of crossings, which yield not only on the average trends like the classical methodologies but additionally high and low extreme value level trends. Hence, instead of a single trend there are three trends with intercept and slope values. The classical Sen slope is replaced by crossing trend straight-line slope formulation. The comparison of the IMCT method with the most frequently used MK approach yields less that ±5% relative error. High and low values' trends are achieved by consideration of plus and minus one standard deviation from the arithmetic average. The methodology application is presented for Danube River annual discharge records. The slopes of 'high', 'average' and 'low' value sets are obtained as 29.34 m3/sec, 1.63 m3/sec and 11.41 m3/sec, respectively. The mean point trend slope is different from the high and low extreme value trend slopes.
Keywords: bi-value; cross; Danube; intercept; multi-slope; pivot; slope; trend; up-crossing; innovative multi-cross trend; IMCT.
International Journal of Global Warming, 2022 Vol.26 No.1, pp.64 - 73
Received: 15 Feb 2021
Accepted: 08 Apr 2021
Published online: 06 Jan 2022 *