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PCIC Regional Analysis Tool - Help

The help below consists of screenshots (images) of the Regional Analysis Tool and instructions for how to use the tool. The images are examples of what the tool will display in specific circumstances - clicking on the images below will have no effect. In order to use the tool, visit tools.pacificclimate.org. Slight differences may exist between the screenshots below and the Regional Analysis Tool as displayed on your computer.

Overview

PCIC Regional Analysis Tool header
PCIC Regional Analysis Tool data options
PCIC Regional Analysis Tool display options
PCIC Regional Analysis Tool update button
PCIC Regional Analysis Tool main page

The controls for the tool are divided up into:

  1. Data options: where the data to work with is selected;
  2. Display (region) options: where the window into the data set and the polygonal region within that are selected; and
  3. Plot (map) options: where tabs can be selected and options pertaining to those tabs can be changed.
Settings only take effect after you click the "Update" button.

Data options

Data options select what part(s) of which data set(s) you will be working with.

PCIC Regional Analysis Tool data options

There are several options:

If you are unfamiliar with climate scenarios, you should read the IPCC's Special Report on Emissions Scenarios (SRES) which covers most currently used climate scenarios.

Display (region) options

Display options is perhaps a misnomer; they do affect what is displayed, but more importantly, they select the grid boxes to provide data about.

PCIC Regional Analysis Tool display options

There are only two options to change here:

Plot (map) options

Again, plot options may be a misnomer. The tabs under this heading allow you to select a region to display, view maps of the data and the grid boxes selected by the defined polygon, view summary about the region, and view scatterplots pertaining to it. Each tab has "side tabs" along the lefthand side which change depending on which tab you have clicked on, and provide related functionality.

The tool will be introduced as we step through a common use case.

Region tab

When you first load the tool, you'll be shown the region tab. This allows you to define your own custom region and set options pertaining to that region:

PCIC Regional Analysis Tool main page

There are several things you can do here:

Next, we'll step through creating a polygon.

Creating a polygon

First, you need to select "Add point" from the map ops select menu, as shown:

PCIC Regional Analysis Tool point menu

Next, you must click on the map where you want a corner of the polygon to be:

PCIC Regional Analysis Tool w/point added

Note that the "Region" field above has changed to "Custom".

Then click again on the map to add each corner:

PCIC Regional Analysis Tool w/region selected

Note that polygons are created incrementally — as you add points, they are inserted into the nearest line to that point.

Suggesting a region

If you think your region might be particularly interesting to PCIC, you can suggest the region to us for addition into the default list of regions by clickin on the "Suggest" sub-tab, filling in the form, and clicking "Suggest Region".

PCIC Regional Analysis Tool showing region suggest form

Maps tab

The PCIC Regional Analysis Tool can display two types of maps: maps of variables, and maps of differences between runs, timeslices or seasons.

First, we'll go over the normal map, and the options available for them:

PCIC Regional Analysis Tool map showing region

There are a few options available:

The options for difference maps are slightly different:

PCIC Regional Analysis Tool map showing difference between runs

For difference maps, you can select the timeslice, time of year, and model-scenario-run combination; these define a data set. This data set then has the main data set or sets selected under Data Options above subtracted from it. If you are differencing from one model to another model on a different grid, the data will be interpolated to a 5 degree common grid. In all cases, the map's data range is dynamic. Here we are looking at the difference between two runs of CGCM3 over Pacific North America.

Data tab

Of course, pretty maps aren't everything. Sometimes you also want to view summary statistics about the data:

PCIC Regional Analysis Tool showing metadata for model

The "Metadata CSV" link at the bottom links you to a CSV version of this data. The Decimal Places selector allows you to change the precision of the output from defaults.

As with most of the tabs in this tool, there are a few options to change:

This is where things get interesting: Our tool allows you to select multiple model-experiment-run combinations, multiple times of year, multiple timeslices, and multiple variables. For our example, we'll select all CGCM3 runs:

PCIC Regional Analysis Tool showing metadata for all runs of model

Displayed here are some summary statistics about the region we selected earlier. The difference is, the experiment field has been changed to "All CGCM3 runs" -- so data about all of the available runs is now being displayed..

Sometimes you have a lot of data to work with, and you want a summary of the summary statistics. For this, we have added a "Percentile calculations" checkbox. Checking this box causes the tool to output these summaries of summaries:

PCIC Regional Analysis Tool showing metadata for all runs of model with percentiles

Last but not least, sometimes you want to work with either the original data, or the data you have selected. For this, you can click on the tab on the left side labelled "Files". There you will find ancillary data, and georeferenced and scenarios format data about the region in question:

PCIC Regional Analysis Tool showing data available for download

Scatter plots tab

PCIC's Regional Analysis Tool also provides two kinds of scatter plots plus box plots. All of these use the experiment (or set of experiments) defined by the Experiment field above; so for meaningful results, please select an ensemble (such as "All CGCM3 runs", which is what we have selected here).

The tool can display box plots:

PCIC Regional Analysis Tool showing boxplots for models for each climatology

There's one option you can change:

Alternatively, you can view the individual model-scenario-run combinations which go into the box plot by viewing scatter plots by timeslice:

PCIC Regional Analysis Tool showing timeslice progression

There's one additional option you can change:

The weighted percentiles mode is shown below:

PCIC Regional Analysis Tool showing timeslice progression of median, 90th, and 10th percentiles

Alternatively you can graph the current variable against another variable:

PCIC Regional Analysis Tool showing temperature versus precipitation

There's one additional option: the X axis variable.

Conclusion

The PCIC Regional Analysis Tool isn't limited to what's demonstrated here. Use your imagination!

Future development

PCIC plans to extend the data available via this tool to include regional data from the Canadian Regional Climate Model, gridded historical data over the world at 0.5 degree resolution, and gridded historical data at 400m resolution over BC. PCIC also plans to improve the interface to provide more easily usable data files.

Disclaimer

The purpose of the Regional Analysis Tool is to explore climate scenarios, to explore the effects of GCM choice on particular regions, and so on. It is not intended to do your homework for you; please don't assume that the results from the Regional Analysis Tool are authoritative, and please don't use results from this interface without checking it yourself or asking a PCIC staff member to check. We can't guarantee that everything here is perfect, and we'd prefer any mistakes we make don't propagate far.

This tool is not designed to distribute data. For the SRES AR4 data, if you wish to use this data for analysis or will be using data from this interface directly for research, you should contact Curt Covey (covey1 -at- llnl.gov) so that he can register you as a user of the SRES AR4 data.

Technical Details

Time periods and averaging

For all experiments, we use the 2010-2039 for 2020s, 2040-2069 for 2050s, and 2070-2099 for 2080s time period convention. Data for SRES and IS92a scenarios are annually or seasonally averaged by a simple average. Data for SRES AR4 scenarios are averaged by weighting each month by the number of model days in the given month.

Experiment naming conventions

In the PCIC Regional Analysis Tool, there are two naming conventions for experiments in use. The first (older) naming convention is used for the SRES and IS92a scenario data, and goes as follows:

This is in contrast to the newer convention, which is used for SRES AR4 scenario data:

Scenario data file format

Each scenario data file contains monthly, seasonal and annual change fields for the selected window, i.e., 17 blocks of data, with each block preceded by a header line. The extent of the Canadian window is dependent upon the GCM from which the scenario has been constructed. The header line is in the same format regardless of which scenario is contained in the data file. This header line contains the following information (in order):

  1. time slice, e.g., (2010-2039)-(1961-1990)
  2. month - Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec, DJF (Winter), MAM (Spring), JJA (Summer), SON (Autumn), ANN (Annual)
  3. climate variable
  4. number of longitude boxes, xdim, (corresponds to the number of columns of data), e.g., 35
  5. number of latitude boxes, ydim, (corresponds to the number of rows of data), e.g., 13
  6. window limits, e.g., Canada: 87.1591N to 42.6776N 168.7500W to 41.2500W

Georeferenced data file format

Each georeferenced data file contains monthly, seasonal and annual change fields for the selected region.

These files are space delimited text files. Each row of data consists of the following 19 columns: latitude, longitude, january data, february data, ... december data, winter (DJF) data, spring (MAM) data, summer (JJA) data, fall (SON) data, annual data.

There is no header line in these data files.

Sea-land mask and region mask format

Mask files are arranged in a space-delimited format, with north at the top, west on the left edge, the number of columns matching the number of grid boxes along the longitude axis, and the number of rows matching the number of grid boxes along the latitude axis. For the sea-land mask, a 1 indicates land, and a 0 indicates ocean. For the region mask, a 1 indicates the region includes that grid box, and a 0 indicates the region does not.

Latitude and longitude format

Latitude and longitude files are arranged in a space-delimited format, with north at the top, west on the left edge, the number of colums matching the number of grid boxes along the longitude axis, and the number of rows matching the number of grid boxes along the latitude axis. Each cell contains the latitude or longitude of the cell in question.