Implementation of a Machine Learning-Based Predictive Model for Assessing pH Variability in Coastal Marine Waters

Öz

The increase in temperature, along with the rise in carbon dioxide (CO₂) concentration in the marine environment, poses a challenge for the marine environment. The decrease in pH (acidification) in oceans and seas has direct effects such as species loss and shifts in dominant species, as well as indirect effects such as the reorganisation of ecological functions and changes in community organisation patterns. This study aims to evaluate the predictive ability of the Gaussian Process Regression (GPR) model, a machine learning method. In this study, sea water parameters (01.06.2022-28.03.2025) from the Black Sea Region (Giresun coast) obtained from the Copernicus Marine Environment Monitoring Service (CMEMS) were used as the data set. Sea water pH was predicted using important parameters such as temperature and partial carbon dioxide surface pressure (spCO₂) in sea water. The findings of this study demonstrate that the Rational Quadratic Kernel GPR, trained with high spatial resolution SST and spCO₂ data provided by Copernicus, offers high accuracy and strong generalisation in pH estimation for the Giresun coast, demonstrating superior performance compared to other kernels and thus establishing a robust scientific foundation for the development of climate-sensitive decision support and early warning systems.

Anahtar Kelimeler

• Machine learning algorithms
• Artificial intelligence-based modeling
• Black Sea
• Climate change impacts
• Acidification

Kıyı Deniz Sularında pH Değişkenliğinin Değerlendirilmesi için Makine Öğrenimi Tabanlı Tahmin Modelinin Uygulanması

Öz

Deniz ortamındaki karbondioksit (CO2) konsantrasyonundaki artışla birlikte sıcaklıktaki artış, deniz ortamı için bir zorluk teşkil etmektedir. Okyanus ve denizlerde pH'ın düşmesinin (asitleşme) tür kaybı gibi doğrudan ve baskın türlerde kaymalar, ekolojik işlevlerin yeniden düzenlenmesi ve topluluk organizasyonu modellerinde değişiklikler gibi dolaylı etkileri vardır. Bu çalışma, bir makine öğrenmesi yöntemi olan Gauss Süreci Regresyonu (GPR) modelinin tahmin yeteneğini değerlendirmeyi amaçlamaktadır. Bu çalışmada, Copernicus Deniz Çevresi İzleme Servisi'nden (CMEMS) elde edilen Karadeniz Bölgesi (Giresun kıyıları) deniz suyu parametreleri (01.06.2022-28.03.2025) veri seti olarak kullanılmıştır. Sıcaklık ve deniz suyundaki kısmi karbondioksit yüzey basıncı (spCO2) gibi önemli parametreler kullanılarak, deniz suyu pH’sı tahmin edilmiştir. Bu çalışmanın bulguları, Copernicus’tan sağlanan yüksek mekânsal çözünürlüklü SST ve spCO₂ verileriyle eğitilen Rasyonel Kuadratik çekirdekli GPR’nin Giresun kıyıları için pH tahmininde yüksek doğruluk ve güçlü genelleme sunduğunu, diğer çekirdeklere kıyasla üstün performans gösterdiğini ve böylece iklim duyarlı karar destek ile erken uyarı sistemlerinin geliştirilmesine sağlam bir bilimsel temel oluşturduğunu göstermektedir.

Anahtar Kelimeler

• Makine öğrenmesi algoritmaları
• Yapay zeka tabanlı modelleme
• Karadeniz
• İklim değişikliği etkileri
• Asidifikasyon

Kaynakça

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