Innovative Polygon Trend Analysis (IPTA): A Case Study for Precipitation in Thessaloniki during the Last 50 Years (1971–2020)

Abstract

In the present study, the introduction of the Innovative Polygon Trend Analysis (IPTA), a non-parametric trend analysis methodology, is proposed as an alternative to the classical trend analysis methodology, according to which processes (normality, independence, and pre-whitening) are not necessary. Monthly precipitation measurements from Thessaloniki are analysed for the period 1971–2020, subdivided into two consecutive equal periods, to identify inherent trends among months and seasons, respectively. A finer interpretation of trends, with physical and numerical explanations and inferences, leads to the obtained results; the total monthly and seasonal precipitation values, their associated standard deviations, as well as trend slopes and trend lengths, are depicted. Increasing trends between the two sub-periods are identified for most months: winter and autumn.

Keywords

• Innovative Polygon Trend Analysis
• non-parametric test
• precipitation trend
• trend slope
• trend length
• Thessaloniki