LONG-TERM ANALYSIS OF HYDROCLIMATIC VARIABILITY IN THE AEGEAN WATER BASIN: A DOUBLE IPTA-BASED APPROACH

Abstract

This study investigates long-term climatic variability in the Aegean Water Basin of Türkiye, focusing on temperature and precipitation dynamics between 1990 and 2024. study area selected due to the region's economic and ecological importance and the research employs the Double Innovative Polygon Trend Analysis (Double IPTA) method to assess seasonal and spatial trends across eight meteorological stations. In result, the Mann-Kendall test revealed no statistically significant trends, but Double IPTA identified nuanced patterns of warming during winter and transitional months, cooling in summer particularly in inland provinces and heterogeneous precipitation shifts, with declines in colder months and increases in spring and summer. Additionally, rising standard deviation values in both temperature and precipitation suggest increasing climatic variability and instability. These findings underscore the enhanced sensitivity of Double IPTA in detecting subtle climate signals and highlight the need for basin-specific adaptation strategies that account for localized seasonal dynamics rather than relying on regional averages. 

Keywords

• Double IPTA
• Aegean Water Basin
• Climate Change
• Trend Analysis
• Temperature
• Precipitation

Ege Su Havzasında Hidroklimatik Değişkenliğin Uzun Vadeli Analizi: Çift IPTA Tabanlı Bir Yaklaşım

Abstract

Bu çalışma, Türkiye'nin batısında yer alan Ege Su Havzası'nda 1990–2024 yılları arasındaki sıcaklık ve yağış değişkenliğini incelemektedir. Bölgenin ekonomik ve ekolojik önemi nedeniyle seçilen çalışma alanında, Çift Yenilikçi Poligon Eğilim Analizi (Double IPTA) ve Man-Kenadall yöntemleri kullanılmıştır. Sıcaklık verileri her iki dönemde (1990–2007 ve 2007–2024) 45° referans çizgisinin üzerinde seyrederek artan bir eğilim göstermiştir. Yağış ve standart sapma (STD) değerleri ise düzensiz dalgalanmalar sergilemiştir. Mann-Kendall testi anlamlı bir eğilim ortaya koymazken, Double IPTA yöntemi mevsimsel ve mekansal düzeyde ısınma, soğuma ve yağış dağılımındaki değişimleri tespit etmiştir. Artan Standart Sapma değerleri, iklimsel değişkenliğin ve aşırı olay riskinin yükseldiğini göstermektedir. Bulgular, yerel mevsimsel dinamikleri dikkate alan havza bazlı uyum stratejilerinin gerekliliğini vurgulamaktadır. 

Keywords

• Çift IPTA
• Ege Su Havzası
• İklim Değişikliği
• Trend Analizi
• Sıcaklık
• Yağış

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