Yavuz Selim Güçlü

Istanbul Technical University

In recent decades, according to Intergovernmental Panel on Climate Change (IPCC) reports, the impact of climate change on hydro-meteorological events has increased substantially. This point is obvious in many rainfall-runoff time-series as a negative or positive trend. In this paper, first of all such trend possibilities are searched graphically ac...

The solar energy has potential future effectiveness in a variety of areas and it helps to decrease the dominance of fossil fuels, which cause atmospheric pollution, global warming and climate change impacts. In the literature, there are different methodologies for its modeling, but this study suggests the harmonic analysis application to solar irra...

During an aquifer test, the depression cone covers various geological formations, and hence, their reflections in time-drawdown data yield noncontinuous scatter of points on double logarithmic paper for type curve matching so as to obtain the aquifer parameters. In this way, transmissivity and storativity parameters are subject to local changes. Al...

Solar irradiation calculations depend on atmospheric variations and sunshine duration record interval. Generally, it is calculated by using the classical Angström–Prescott equation, which provides a linear relationship between the solar irradiation and sunshine duration. Also few 2nd and 3rd degree solar radiation and sunshine duration models are p...

In this study, Angstrom equation solar radiation estimation values corresponding to the sunshine durations are achieved by a linear equation, which is an improvement over the classical model. The results turn out to be better than the classical Angstrom equation. In the suggested equation, 1–10 days’ solar irradiation values are assumed to affect t...

In this study, time series data is divided into two equal parts, as in the basic principle of the Innovative Trend Analysis (ITA) method. However, unlike the ITA, the data are not ordered when comparing the halves to avoid any change in the time series. Wilcoxon Signed Rank Test is used to consider the differences between the two equal halves and t...

The classical trend approaches are implemented frequently in hydrological and meteorological measurements. Nowadays, Şen's innovative trend analysis (ITA) test provides the ability to illustrate inspection and determination of trend status via two-dimensional graph. The main purpose of this study is to attempt determination and visualization of tre...

Sera gazı miktarındaki ciddi artışla birlikte iklim değişikliği daha da hızlanmıştır. Meteorolojik ve hidrolojik veriler incelendiğinde bu değişikliğin etkisi net biçimde ortaya çıkmaktadır. Verilerin incelenmesi için de eğilim çözümleme yöntemleri sıklıkla kullanılmaktadır. Son zamanlarda Şen’in geliştirdiği Yenilikçi eğilim çözümlemesi (YEÇ) yönt...

Probability (PDF) and cumulative distribution function (CDF) are used extensively to calculate probability features in engineering, natural sciences, hydrology, meteorology and many other fields. In this study, a different type of Burr distribution is suggested, which provides an alternative probability calculation. The type is fitted to the Weibul...

The classical trend tests are applied frequently in meteorological and hydrological data. Recently, Şen-innovative trend analysis (ITA) method provides the ability to visualize inspection and identification of trend conditions. The main objective of this paper is to attempt determination and visualization of trends by means of a special graphical r...

This paper focuses on sea surface temperature (SST) trends due to the importance of temperature difference in climate change impact research. These trends are not only essential for climate, but they are also important for marine ecosystem. Immigration of fish population due to the temperature changes is expected to cause unexpected economical resu...

This study compares classical Mann-Kendall (MK) test and simple Şen-innovative trend analysis (ITA) method by proposing a new trend analysis methodology with a special graphical representation. Another attempt is to classify sub-categories as “low” and “high” objectively by means of the Pettit change point test. The applications are based on 50-yea...

In this study, based on the Şen innovative trend analysis (ITA) method, another approach has been developed as innovative triangular trend analysis (ITTA), which helps to identify partial trends within a given time series comparatively with each other. The basis of this methodology is to divide a given time series into a set of equal length sub-ser...

Dünyanın en önemli enerji kaynağı güneş enerjisi, çeşitli alanlarda farklı konular altında araştırılmaktadır. Özellikle, fosil yakıt kaynaklarının azalmasından beri güneş enerjisinin değeri ve önemi daha da artmıştır. Güneş enerjisi ile ilgili ilk araştırmalar 20. yüzyılın ilk çeyreğinde başlamış ve bu tür çalışmaların ilki güneş ışınımının güneşle...

Istanbul is one of the megacities with population over 14 million, where the most intensive economic and social human activities take place in Turkey with unprecedented energy consumption and extravagant life style. These activities cause air pollutant emissions and concentrations increases under the additional effects of greenhouse gasses and wast...

Bu çalışma Yavuz Sultan Selim Köprüsü’ne bağlantıyı sağlayan Kuzey Marmara Otoyolu’nun Ümraniye Alemdağ dere köprüsüne ait hidrolojik, hidrolik ve boyutlandırma hesaplarını içermektedir. Bu çalışmada kullanılan veriler Meteoroloji Genel Müdürlüğü (MGM)’nden alınmıştır. İstanbul’un 33 m rakımlı Göztepe yağış istasyonunda yapılmış ölçümler 1942-2007...

The climate change is an important event that affects hydrological, agricultural and water resources planning variables, and therefore, the hydrologists and meteorologists frequently try to identify trend possibilities especially in rainfall, runoff and temperature time series. For this purpose, the classical Mann-Kendall (MK), Spearman’s rho (SR),...

The solar energy as one of the most important energy sources is investigated for effective use in a variety of areas. Especially, with the tendency of depletion of fossil fuel consumption as well as their greenhouse gas emissions leading to atmospheric pollution and, hence, global warming and climate change, the value of renewable energy sources an...

Son zamanlarda birçok hidrolojik ve meteorolojik verilerde artan veya azalan trendler (eğilimler) ortaya çıkmaktadır. Bu makalede eğilim analizini (çözümlemesi) herhangi bir kabule gerek duymadan gerçekleştiren Şen’in 1:1 doğru yöntemi ele alınmıştır. Daha önemlisi, diğer bir adı Yenilikçi Eğilim Çözümlemesi olan bu yöntem geliştirilmiştir. Yenilik...

This paper attempts to determine and visualize the trends by considering the value via Şen’s innovative trend analysis methodology, which has been suggested instead of the well-known approaches called Mann-Kendall (MK), Spearman’s rho (SR), Sen’s slope, and linear regression methodologies. Another attempt is to show that an additional trend approac...

Hydrological variables are under the effect of the climate change impacts, and therefore, this study concentrates on the frequency analyses of low and high flows depending on the duration leading to a new approach. The durations are selected as month, season, 6-month and year coupled with the return periods 2-year, 5-year, 10-year, 20-year, 50-year...

Evapotranspiration (ET) is one of the main hydrological cycle components that has extreme importance for water resources management and agriculture especially in arid and semi-arid regions. In this study, regional ET estimation models based on the fuzzy logic (FL) principles are suggested, where the first stage includes the ET calculation via Penma...

Hydro-meteorological time series may include trend components mostly due to climate change since about three to four decades. Trend detection and identification in a better and refined manner are among the major current research topics in water resources domain. Even though different methodologies can be found for trend detection in literature, two...

Hydrograph peak discharge estimation is gaining more significance with unprecedented urbanization developments. Most of the existing models do not yield reliable peak discharge estimations for small basins although they provide acceptable results for medium and large ones. In this study, fuzzy chain model (FCM) is suggested by considering the neces...

Şen (2012) proposed the innovative trend analysis methodology and gave its fundamentals in a simple way based on logical deductions. Later, this methodology has been applied by many writers to different data as mentioned by Kisi and Ay (2014) and Kisi (2015), who also implemented the same methodology. In one of illustrations in their paper (Kisi an...