Matlab codes for two breakpoint checken

(1)  累计距平均

data=xlsread(‘test.xlsx’);

data(:,1)=[];

mean_data=mean(data);

diff_streamflow=data(:,1)-mean_data(1);

diff_baseflow=data(:,2)-mean_data(2);

diff_surfq=data(:,3)-mean_data(3);

Sum_streamflow_anomaly=zeros(55,1);

Sum_baseflow_anomaly=zeros(55,1);

Sum_surfq_anomaly=zeros(55,1);

for i=1:55;

Sum_streamflow_anomaly(i)=sum(diff_streamflow(1:i));

Sum_baseflow_anomaly(i)=sum(diff_baseflow(1:i));

Sum_surfq_anomaly(i)=sum(diff_surfq(1:i));

end

years=(1960:2014)’;

xlswrite(‘cumulative_anomaly.xlsx’,[years,Sum_streamflow_anomaly,Sum_baseflow_anomaly,Sum_surfq_anomaly])

通过绘图找到分界点即得到break point

(2)   Pettitt检测

% This code is used to find the change point in a univariate continuous time series

% using Pettitt Test.

%

%

% The test here assumed is two-tailed test. The hypothesis are as follow:

%  H (Null Hypothesis): There is no change point in the series

%  H(Alternative Hypothesis): There is a change point in the se[……]

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A paper published in JoH

Application of the MacCormack scheme to overland flow routing for high-spatial resolution distributed hydrological model

Although process-based distributed hydrological models (PDHMs) are evolving rapidly over the last few decades, their extensive applications are still challenged by the computational expenses. This study attempted, for the first time, to apply the numerically efficient MacCormack algorithm to overland flow routing in a representative high-spatial resolution PDHM, i.e., the distributed hydrology-soil-vegetation model (DHSVM), in order to improve its computational efficiency. The analytical verification indicates that both the semi and full versions of the MacCormack schemes exhibit robust numerical stability and are more computationally efficient than the conventional explicit linear scheme. The full-version outperforms the semi-version in terms of simulation accuracy when a same time s[……]

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A paper published in STOTEN

Comparison of baseline period choices for separating climate and land use/land cover change impacts on watershed hydrology using distributed hydrological models

  • Key Laboratory of Remote Sensing of Gansu Province, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
  • Ministry of Education Key Laboratory of Virtual Geographic Environment, Nanjing Normal University, Nanjing 210023, China
  • Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China
  • College of Hydrometeorology, Nanjing University of Information Science & Technology, Nanjing 210023, China

Abstract

Separating impacts of land use/land cover change (LUCC) and climate change on hydrology is essential for watershed planning and management. This is typically done via hydrological modelling in combination with the on[……]

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ArcGIS Licience过期的解决方法

今天需要用ArcGIS workstation处理一些数据。结果发现arggis的licience出现错误。如下:

我check了一下我的licience 文件,如下。可以看到,licience的有效日期是11月17号

为了解决这个问题。两种方法:

(1)修改系统时间,修改到过去的时间,这种方法简单有效。

(2)重装Licience

我这里选用第一种方法,测试有效。