To check the outliers for temperatures data, use the menu . It will display a tabbed widget on the left panel, allows
to enter the inputs data and parameters.
The tab Data allows to enter
the inputs data and set the parameters for the QC.
- Select the time step of the station data to be checked.
- Choose the variable to be checked between the maximum and minimum
temperature.
- Select from the drop-down list the file containing the station data
to be checked if it is already loaded, or open it from the browse button
on the right.
- If TMAX is selected in (2), this should be the file
containing the maximum temperature.
- If TMIN is selected in (2), this should be the file
containing the minimum temperature.
- Select from the drop-down list the file containing the station data
to be used to check if the minimum temperature is greater than the
maximum.
- If TMAX is selected in (2), this should be the file
containing the minimum temperature.
- If TMIN is selected in (2), this should be the file
containing the maximum temperature.
- Click on this button to set the parameters to perform the outliers
check
- Type the full path to the folder to save the results of the outliers
check, or use the browse button .
- Click the button Check Outliers
to run the quality control.
This creates a folder named TMAX.OUTLIERS.CHECK_data
or TMIN.OUTLIERS.CHECK_data under the folder you
provided (6) to save the results of the outliers check.
Inside this folder 2 directories and 1 file are created:
- CDTDATASET: directory containing all the required
files used by CDT
- CDTSTATIONS: directory containing the checked data,
when you did a correction on the suspicious values. The name of the file
containing the corrected data is the same as the name of the file from
the input (3).
- OutliersCheck.rds: an index file, you will need to
reload the outputs of QC if you want to view the results or to continue
the correction of suspicious values later.
The tab QC Outputs allows to
view the results of the QC.
- If you already performed an outliers check, you do not need to run
it again, you can check this box, the input field below will be
activated and you can provide the full path to
OutliersCheck.rds under the folder
TMAX.OUTLIERS.CHECK_data or
TMIN.OUTLIERS.CHECK_data by browsing it through the
button on the
right.
- The stations with suspicious values are listed here. You can select
a station and click on the button View
& Edit Result to view and edit the result of the QC
for this station. You can use the buttons
<< or >> to
switch to the previous or next station. It will open a table on the
right panel showing the output of the QC for the selected station.
(a) The ID of the station.
(b) The dates on which suspicious values are
found.
(c) The observed suspicious values.
(d) Statistics from the temporal check if
available.
(e) Statistics from the spatial check if
available.
(f) Description of the suspicious value from
temporal check.
- lower.values: the value is flagged as too
small compared to the time series from this month;
- upper.outliers: the value is flagged as
too large compared to the time series from this month;
- TMIN >= TMAX: the minimum temperature
is greater than the maximum temperature;
- greater.than.maximum.values: the value is
greater than the maximum possible value you provided when you set the
parameters of the QC;
- less.than.minimum.values: the value is
less than the minimum possible value specified.
(g) Description of the suspicious value from
spatial check.
- spatial.not.outliers: the value is flagged
as outlier from the temporal check but not an outlier when a spatial
check is performed;
- upper.outliers: the value is flagged very
high compared to the values of the neighbor stations;
- lower.outliers: the value is flagged very
small compared to the values of the neighbor stations.
(h) The estimated value from the
regression.
(i) You can specify here an action to take when
you want to correct the suspicious value. By default, the value in this
column is 1, this means no correction will be done. If
you put a flag 1 in this column, the corresponding
value in column (c) will be kept. If you put a flag
2, the corresponding value in column
(c) will be replaced by the estimated value in column
(h). If you leave this column blank, the corresponding
value in (c) will be replaced by missing
value.
(j) If you put a value in this column, this
value will be taken to replace the value in (c). This
column takes the priority, whenever you put a flag 1,
2 or leave blank the column
(i).
After editing this table, you have to save the changes you made. You
can go to the menu
or click on the button in the toolbar to
save the table. If the table is saved correctly, you should see an
output message “Table saved successfully”.
- Select here the month to display a chart of the time series for this
month and the suspicious values detected from the temporal check. If you
select the month from the drop-down list, click on the button PLOT to display the chart. You can use
the buttons << and >> to switch to the previous or
next month.
- Select here the date corresponding to a suspicious value to plot it
on a map for this date. If you select the date from the drop-down list,
click on the button PLOT to
display the map. You can use the buttons
<< and >>
to switch to the previous or next date.
- After saving the changes you made on the table, click on the button
Replace Outliers for the
changes to take effect.
To replace all the values flagged as suspicious for all stations by
missing values, use the following command to the R
console:
indexQC <- "/<path_to>/TMAX.OUTLIERS.CHECK_data/OutliersCheck.rds"
CDT:::QC.TT_replaceAll(indexQC, action = "all")
Change <path_to> with exact path. The
corrected data are located under the folder
TMAX.OUTLIERS.CHECK_data/CDTSTATIONS.
You can do the same for the minimum temperature by replacing
TMAX by TMIN.
The tab Zoom allows to zoom
the displayed map.
- Enter here the bounding box of the area to be displayed on the
map.
- After setting the bounding box (1), click this button for the change
to take effect.
- Reset the zoom.
- Zoom in
- Zoom out
- Draw a rectangle on the map to zoom in an area.
- Move the displayed map.
Right click on the map to deactivate the active zoom.
The tab Add Layers allows to
superpose other layers.
- Check the box and select the shapefile from the drop-down list or
open it from to add
boundaries to the active map.
- Check the box and select the NetCDF file containing the DEM (Digital
Elevation Model) from the drop-down list or open it from to add elevation data as
background to the active map.
- Check the box and enter or browse the full path to the NetCDF data
(from satellite or radar) to display. Do not forget to provide a sample
file and change the filename format by clicking on the button Settings (see Setting NetCDF data for
more details).
- Select the type of the map. You can choose between a pixel-based
image or a contour map.