Sentinel-2 görüntülerinin kullanımıyla batimetri analizi

Öz

Batimetri, Deniz ve Okyanus derinlik ölçümleri olarak tanımlanmakta ve birçok yöntemle yapılmaktadır. Geçmişten günümüze kadar hala kullanılan geleneksel yöntemler, teknolojinin gelişmesiyle yerini modern yöntemlere bırakmıştır. Sonar sistemleri, LIDAR ve uzaktan algılama sistemleri bu modern yöntemlerin örnekleri olarak listelenmiştir. Akustik sistemlerin veya LIDAR'ın kullanımı hem zaman hem de maliyet açısından ekonomik değildir. Bu çalışmada zaman ve maliyeti en aza indirmek için uzaktan algılama yöntemleri araştırılmıştır. Batimetri ile ilgili bilgilerin ücretsiz uydu görüntüleri kullanılarak çıkarılması amaçlanmaktadır. Kullanılan yöntem verileri, farklı dalga boylarında alınan Sentinel-2 uydu görüntülerini ve referans batimetri değerlerini içerir. Daha sonra bu veriler bant oranı ve çok bantlı yöntemlerde kullanılarak regresyon analizleri yapılmıştır. Regresyon analizi ile elde edilen katsayılar ile, referans derinliğe ihtiyaç duyulmadan derinliği bilinmeyen yerlerde yukarıdaki yöntemler kullanılarak batimetri tahmini yapılmıştır. Bant oranı ve çok bantlı yöntemler kullanılmış ve sonuçlar değerlendirilmiştir. Her iki yöntemden elde edilen batimetrik haritalar bölgenin gerçek derinlik değerleri ile analiz edilmiş ve hata miktarı hesaplanmıştır. En yüksek doğruluk, mavi bandın yeşil banda oranından elde edilmiştir. Kırmızı bandın bozucu bir etkiye sahip olduğu görülmüştür .

Anahtar Kelimeler

• Uzaktan Algılama
• batimetri
• LIDAR
• Sentinel-2

Bathymetry analysis with use of Sentinel-2 images

Abstract

Bathymetry is described as Sea and Ocean depth measurements, and performed by many methods. Traditional methods, which are still used from the past to the present, have been replaced by modern methods with the development of technology. Sonar systems, LIDAR and remote sensing systems are listed as examples of these modern methods. The use of acoustic systems or LIDAR, are not economical in terms of both time and cost. In this study, remote sensing methods are investigated in order to minimize the time and cost. It is aimed to extract the information about bathymetry with use of free of charge satellite images. The method data used includes Sentinel-2 satellite images taken at different wavelengths and reference bathymetry values. Later, regression analyzes were made by using these data in band ratio and multi-band methods. By using the coefficients obtained by the regression analysis, the bathymetry estimation was made in places with unknown depth using the above methods without the need for reference depth.Band ratio and multi-band methods are used, and the results were evaluated. Bathymetric maps obtained from two methods were analyzed with the ground-truth values of the region and the amount of error was calculated. The highest accuracy was obtained from the ratio of blue band to green band. It has been observed that the red band has a disruptive effect.

Keywords

• Remote sensing
• Bathymetry
• LIDAR
• Sentinel-2

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