Data Access

Most of the NA-CORDEX dataset has now been published!

>> Download data from the NA-CORDEX search page on NCAR's Climate Data Gateway. <<

Downloading Data

The NA-CORDEX search page on the NCAR Climate Data Gateway data portal lists options for different data facets of the collection. Use the checkboxes to select the features you want, then click the "Search" button.

Matching results will be listed below on the same page. You can download individual files by clicking on their names. To download multiple files in a batch, you can select them using checkboxes, then click "Download Wget Script"; the resulting script can be run natively on Linux and Mac systems and in a Linux emulator or virtual machine on Windows systems.

For example, if you were interested in monthly-average temperature and precipitation from ERA-Interim driven runs at 25-km resolution on the native grid, you'd select "pr" and "tas" under Variables, "ERA-Int" under Driver, "mon" under Frequency, and "NAM-22" under Grid. Because nothing was selected under Model, the search will return results for all models with data fitting the other criteria. Within a category, the search returns results matching any of the selections; between categories, the results must match a selection in each category.

Subsetting Data

The CDG data portal will now allow you to subset the data to a region of interest. The subset service currently only functions correctly on data that has been interpolated to the common lat-lon grid, so be sure to search for "NAM-22i" or "NAM-44i" for the Grid value. To the right of each file in a search result is a "Subset" link that will take you to the NetCDF Subset Service built into the data portal engine.

To subset data, first, click the checkbox to select the variable. Although NA-CORDEX files only contain one data variable, the engine doesn't yet know to automatically select it. Next, enter values for a lat-lon bounding box in the panel labeled "Horizontal subset". Click the "Submit" button at the bottom of the page (you may need to scroll down) to download the subset data.

Notes: The map showing the spatial coverage of the data is currently not working. For NA-CORDEX data, longitude values will generally be negative. The bounding box must fit entirely within the spatial domain of the data. If you encounter an error, don't forget to redo the first step (selecting the variable) when you go back to the subset page.

You can also subset the data in time. Currently, when the page loads, the "Time subset" panel has a bug that causes it to display the controls for both "Time range" and "Single time" subsets; click one of the two labels to resolve it to one or the other. Start and end dates can be abbreviated.

Data Availability

Some variables may not be available for all simulations. The data portal usually goes offline briefly once a week for software updates.

Alternative Options

NA-CORDEX data is also available from the Earth System Grid Federation (ESGF). The ESGF archives typically hold a longer list of variables, but fewer or no derived data products (regridded, aggregated, and bias-corrected data). ESGF data nodes vary with regard to which simulations they hold data from, although they all share catalogs and can provide pointers to data at other node. CORDEX-specific search pages can be found at these ESGF nodes: