Analysis of Absorbing Aerosols for Ground-Based Astronomical Observatories in Türkiye

Abstract

In this study, the impact of aerosols on ground-based astronomical observations in Türkiye was examined, and their spatial and temporal variations were assessed. Satellite data was used in the study due to its advantage of wide area coverage. The absorbing aerosol index (AAI) product, derived from multi-sensor observations, was utilized in the research. Positive AAI (PAAI) is a measurement of the concentration of absorbing aerosols (such as dust, smoke, volcanic ash, etc.) in the atmosphere. High PAAI values are often indicative of significant weather events, such as dust storms, forest fires, and volcanic eruptions. Therefore, PAAI values serve as an important indicator for atmospheric conditions affecting astronomical observations. The study revealed the current aerosol characteristics of the observatories in detail. The global average PAAI value for 2024 is calculated to be 0.34, which is lower than the 45-year long-term global average of 0.38. However, the average PAAI value for Türkiye in 2024 is 0.38, which is consistent with the long-term global average. These findings indicate that the observatories in Türkiye are closely aligned with the global average aerosol conditions. The results provide significant insights into the evaluation of astronomical observation data accuracy, the planning of observation programs, and the selection of suitable observation sites. Understanding the impact of atmospheric aerosols on photometric and spectroscopic data is critical for improving the success of future high-precision astronomical observations.

Keywords

• Absorbing Aerosol Index
• Astronomy
• Remote Sensing
• Spatiotemporal Analysis
• Türkiye

Türkiye'deki Yer Tabanlı Astronomi Gözlemevleri için Soğurucu Aerosollerin Analizi

Öz

Bu çalışmada, Türkiye'deki yer tabanlı astronomik gözlemler üzerinde aerosollerin etkisi incelenmiş, aerosollerin mekânsal ve zamansal değişimleri değerlendirilmiştir. Çalışmada geniş alan kapsama avantajı nedeniyle uydu verileri tercih edilmiş, çoklu sensör gözlemlerinden türetilen Absorbe Edici Aerosol İndeksi (AAI) ürünü kullanılmıştır. Pozitif AAI (PAAI), atmosferdeki ışığı absorbe eden aerosollerin (toz, duman, volkanik kül gibi) yoğunluğunu ölçen bir parametredir. Yüksek PAAI değerleri, genellikle toz fırtınaları, orman yangınları ve volkanik patlamalar gibi büyük ölçekli atmosferik olayların varlığını göstermektedir. Bu nedenle, PAAI değerleri astronomik gözlemler için atmosferik koşulların belirlenmesinde önemli bir gösterge olarak kullanılmaktadır. Çalışma sonucunda, Türkiye’deki gözlemevlerinin mevcut aerosol özellikleri ayrıntılı biçimde ortaya konmuştur. 2024 yılı için küresel ortalama PAAI değeri 0,34 olarak hesaplanmış ve bu değer 45 yıllık uzun dönem küresel ortalama olan 0,38'in altında bulunmuştur. Öte yandan, Türkiye'nin 2024 yılı ortalama PAAI değeri 0,38 olarak ölçülmüş ve uzun dönem küresel ortalama ile uyumlu olduğu belirlenmiştir. Bu bulgular, Türkiye’deki gözlemevlerinin, atmosferik aerosol koşulları açısından dünya ortalamasına yakın değerlere sahip olduğunu göstermektedir. Elde edilen sonuçlar, astronomik gözlem verilerinin doğruluk düzeylerinin değerlendirilmesi, gözlem programlarının planlanması ve uygun gözlem yerlerinin seçimi açısından önemli katkılar sunmaktadır. Atmosferik aerosollerin fotometrik ve spektroskopik veriler üzerindeki etkilerinin anlaşılması, gelecekteki yüksek hassasiyetli astronomik gözlemlerin başarısını artırmak için kritik öneme sahiptir.

Anahtar Kelimeler

• Soğurucu Aerosol İndeksi
• Astronomi
• Uzaktan Algılama
• Mekansal-Zamansal Analiz
• Türkiye

Kaynakça

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