The AODN Portal provides access to the following types of gridded datasets:
- Sea Surface Temperature (SST) products
- Ocean Colour products
- Satellite altimetry products
- Climatology products
- Bathymetry (coming very soon)
Many of these gridded data collections are very large and therefore require sub-setting to be able to download from the Australian Ocean Data Network (AODN) Portal. Step 2 of the AODN Portal is used to subset the collection by time and space.
GoGoDuck is a tool that allows data products to be partitioned temporally and spatially as well as aggregated into a single file. It allows users to create aggregations by selecting various constraints, i.e. date and area of interest directly through the AODN Portal.
Two different types of download options are available to the user depending of the filers used in step 2.
In the first scenario, a user will select a spatial and/or temporal extent filter in step 2 and the following download options will be available in step 3 of the AODN Portal:
- Un-subsetted netCDFs
- List of URLs
The "netCDF" option provides a single netCDF file. This file only contains data that is matching the spatial and temporal constraints selected by the user.
The "Un-subsetted netCDFs" option provides in a ZIP folder all the original netCDF files matching the spatial and temporal constraints selected by the user.
The "List of URLs" option supplies a text file with a list of URL links to the original netCDF files which can be used programmatically or individually.
In the second scenario, a user will select the "Point timeseries" check box in step 2, enter the latitude and longitude of the point of interest and the following download option will be available in step 3 of the AODN Portal:
The "CSV" option provides a single CSV file with a timeseries of the associated variable for the selected time range.
The "CSV" option was implemented a few months ago in response to feedback received from multiple users wishing to download a timeseries of several years of gridded data at a single location in a simple data format.
In the past few weeks the AODN Team have been assisting a PhD student at the University of Queensland, who is looking at the population structure of Dugongs along the Queensland coast and what may be influencing connectivity between populations, in gathering aggregated data near her sample sites.
For this research the PhD student has used the AODN Portal to obtain Sea Surface Temperature (SST) data, concentration of chlorophyll from one of the Ocean Colour products and current speed and direction from satellite altimetry products.
The PhD student has used the AODN Portal to download timeseries data for several locations along the Queensland coast for a 10 year period. The ability to download a subsetted and aggregated data file for very specific sampling locations is particularly useful in this context because it avoids having to download large volumes of data for each different type of data product.
This use case has also provided the AODN team with some valuable insight into the current use of the "Point timeseries" feature and ideas for possible future improvements that could be made, one such idea may be the ability to select more than one location at a time before moving to step 3 and downloading the corresponding data.