ch_flow_raster_trend {CSHShydRology} R Documentation

## Raster plot and simple trends of observed streamflows by periods

### Description

Creates a raster plot plus trend plots for day of year, which are binned by a number of days (step), and the max, min, and median annual discharge across years. The plot contains four panels based upon binned data.

### Usage

ch_flow_raster_trend(
DF,
step = 5,
missing = FALSE,
colours = c("lightblue", "cyan", "blue", "slateblue", "darkblue", "red")
)


### Arguments

 DF - dataframe of daily flow data as read by ch_read_ECDE_flows step - a number indicating the degree of smoothing eg. 1, 5, 11. missing If FALSE years with missing data are excluded. If TRUE partial years are included. metadata a dataframe of station metadata, default is HYDAT_list. colours A vector of colours used for the raster plot. The default is c("lightblue","cyan", "blue", "slateblue", "darkblue", "red").

### Details

The four plots are: (1) The maximum,minimum,and median flow with a trend test for each period: red arrows indicate decreases, blue arrows indicate increases. (2) The scale bar for the colours used in the raster plot, (3) The raster plot with a colour for each period and each year where data exist, and (4) A time series plot of the minimum, median, and maximum annual bin values. If there is no trend (p > 0.05) the points are black. Decreasing trends are in red, increasing trends are in blue.

### Value

Returns a list containing:

 stationID Station ID eg. 05BB001 missing How missing values were used FALSE = used, TRUE = removed step number of days in a bin periods number of periods in a year period period numbers i.e. 1:365/step bins values for each period in each year med_period median for each period max_period maximum for each period min_period minimum for each period tau_period Kendalls Tau for each period prob_period probability of Tau for each period year years spanning the data median_year median bin for each year max_year maximum bin for each year min_year minimum bin for each year tau_median_year value of tau and probability for annual median tau_maximum_year value of tau and probability for annual maximum tau_minimum_year value of tau and probability for annual minimum

Paul Whitfield

### References

Whitfield, P. H., Kraaijenbrink, P. D. A., Shook, K. R., and Pomeroy, J. W. 2021. The Spatial Extent of Hydrological and Landscape Changes across the Mountains and Prairies of Canada in the Mackenzie and Nelson River Basins Based on data from a Warm Season Time Window, Hydrology and Earth Systems Sciences 25: 2513-2541.

ch_flow_raster
 data(CAN05AA008)