Climate change effects on annual streamflow of Filyos River (Turkey)

Abstract The main purpose of this study was to estimate possible climate change effects on the annual streamflow of Filyos River (Turkey). Data for annual streamflow and climatic parameters were obtained from streamflow gauging stations on the river and Bartın, Karabük, Zonguldak meteorological observation stations. Time series analysis was performed on 46 years of annual streamflow data and 57 years of annual mean climatic data from three monitoring stations to understand the trends. Pettitt change-point analysis was applied to determine the change time and trend analysis was performed to forecast trends. To reveal the relationship between climatic parameters and streamflow, correlation tests, namely, Spearman's rho and Kendall's tau were applied. The results of Pettitt change-point analysis pointed to 2000 as the change year for streamflow. Change years for temperature and precipitation were detected as 1997 and 2000, respectively. Trend analysis results indicated decreasing trends in the streamflow and precipitation, and increasing trend in temperature. These changes were found statistically significant for streamflow (p < 0.05) and temperature (p < 0.01). Also, a statistically significant (p < 0.05) correlation was found between streamflow and precipitation. In conclusion, decreasing precipitation and increasing temperature as a result of climate change initiated a decrease in the river streamflow.

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Trend analysis and forecasting of the Gökırmak River streamflow (Turkey)

Oceanological and Hydrobiological Studies ◽

10.1515/ohs-2020-0021 ◽

2020 ◽

Vol 49 (3) ◽

pp. 230-246 ◽

Cited By ~ 1

Author(s):

Gökhan Arslan ◽

Semih Kale ◽

Adem Yavuz Sönmez

Keyword(s):

Time Series ◽

Trend Analysis ◽

Change Point ◽

Moving Average ◽

Arima Model ◽

Change Point Analysis ◽

Point Analysis ◽

Monthly Streamflow ◽

Model Time Series ◽

Streamflow Trend

AbstractThe objective of this paper is to determine the trend and to estimate the streamflow of the Gökırmak River. The possible trend of the streamflow was forecasted using an autoregressive integrated moving average (ARIMA) model. Time series and trend analyses were performed using monthly streamflow data for the period between 1999 and 2014. Pettitt’s change point analysis was employed to detect the time of change for historical streamflow time series. Kendall’s tau and Spearman’s rho tests were also conducted. The results of the change point analysis determined the change point as 2008. The time series analysis showed that the streamflow of the river had a decreasing trend from the past to the present. Results of the trend analysis forecasted a decreasing trend for the streamflow in the future. The decreasing trend in the streamflow may be related to climate change. This paper provides preliminary knowledge of the streamflow trend for the Gökırmak River.

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Global and Local Trend Analysis and Change-Point Analysis of Selected Financial and Market Indices

Journal of Automation Mobile Robotics & Intelligent Systems ◽

10.14313/jamris/3-2019/28 ◽

2019 ◽

Vol 13 (3) ◽

pp. 56-63

Author(s):

Dominika Ballová

Keyword(s):

Trend Analysis ◽

Change Point ◽

Change Point Analysis ◽

Point Analysis ◽

Local Trend ◽

Global And Local

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Temperature and Rainfall Partial Trends in Oxford, 1870-2019

10.21203/rs.3.rs-357799/v1 ◽

2021 ◽

Author(s):

Eyüp Şişman ◽

Burak KIZILÖZ

Keyword(s):

Climate Change ◽

Time Series ◽

Trend Analysis ◽

Temperature Increase ◽

Innovative Design ◽

Monotonic Trend ◽

Climate Change Effects ◽

The Past ◽

Temperature And Precipitation ◽

Average Precipitation

Abstract In this study, the trends and stabilities of temperature and precipitation hydro-meteorology time series recorded since 1870 in Oxford city of England were analyzed in detail. The Innovative Triangular Trend Analysis (ITTA) method has been inspired to identify and analyze the trends and stabilities of the selected time series. To compare the results obtained by the above-mentioned method, the Classical Mann Kendall (MK) method has been applied to each series determined for ITTA design. Thanks to the innovative design of ITTA which is preferred by the Classic MK and Sen slope methods, the trends of time series could be analyzed in detail. In this study, the first draft structure has been improved with the help of ± 5-±10 % percentage change levels which were added to the ITTA method, and thus more objective evaluations about the trend magnitudes in time series is possible. For the same draft, the monotonic trend slopes which were found by the classical MK were also calculated through the Sen slope method. The data trends could explain in more detail with the help of the draft used in this study, compared to the studies in the literature. Climate change, which has been the most important factor in trend formation in recent years, has been taken into consideration while determining the design series. The thirty-year period up to 2019, a year in which the climate change was felt much more, constitutes the most important reference years for the analysis beginning from 1990, a year in which the climate change effects started to emerge. When the data trends of one hundred fifty years are examined for the different sub-time series, it is seen that the temperature increase in during1990-2019 period is much higher than the past hundred and twenty years, according to the analysis results. The highest average precipitation occurred in the 1990–2019 and 1900–1929 periods, and their amounts and patterns are nearly similar.

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