Downloading Data with The National Map Download Client
In this lesson, we will discuss the process of using the National Map download client
to download data.
The next lesson will cover using this client to download maps.
Here we are at the launch page for the National Map data download and visualization services.
If you haven’t already, please bookmark this address now for future reference.
You can access the National Map Download Client by clicking on download GIS data under the
GIS Data section or under the “Applications” section.
The National Map Download Client will display in a new browser tab or window.
Using The National Map Download Client is basically a two stage process.
First you will define your area of interest using a variety of map tools.
The second step is to select the products you are interested in.
Let’s select an area in central Illinois.
After determining your area of interest, select the dataset that you would like to download
- You can select one or more datasets of interest
on the left-hand side of the screen.
Because searches are fast we recommend selecting a single dataset at a time and repeating for
other datasets.
There are two sections, Map and Data.
Another lesson will discuss selecting and downloading maps.
In this lesson, we’ll focus on downloading data.
Clicking the checkbox next to a dataset category opens up additional information about the
dataset that helps to further refine the search or provide information about the availability
or content of the dataset.
For example, clicking the Elevation Products checkbox shows a number of subcategories which
can be selected as desired.
The ? arc-second DEM is selected by default.
There are also options for selecting a File Format and Data Extent.
Products that do not cover the entire US often have Product Availability layers that can
be turned on to display the available coverage areas for a specific product on the map to
help identify whether data is available within the desired Area of Interest.
You can see that in this case, our area of interest has no coverage for 1/9 arc-second
DEMs.
However, the entire area is covered by 1/3 arc-second DEMs.
You can see selected product previews and read a description of the dataset.
Having defined the area of interest, selected the desired datasets, subcategories, extent
and format - clicking the find products button will allow you to search for available products.
Please note that selecting the product in the product availability layer does not change
your selection in the filter.
The results will appear under a new ‘Products’ tab.
You can go back to the datasets tab to refine your search.
Each product result will include the product title, the published date, the last date the
metadata was updated along with the format and size of the downloaded product and the
extent.
A number of Action links can be found next to each product to draw the Footprint or Thumbnail
on the map, zoom to the product extent on the map, and obtain additional data or metadata
about the product.
You can also directly download each product in the list by clicking on the download button.
Clicking the show footprints or show thumbnails at the top of the list
shows them for all of the current page.
Once you draw a thumbnail or footprint, you can then click hide footprints or thumbnails.
Be aware that you may have several pages of results, and can navigate between those pages
using the links here.
The Cart buttons can be used to add or remove specific products to or from the Cart.
The Add All button can be used to add all the currently visible products to the Cart
without having to click each individual item.
The View Cart button will create a Cart tab which shows a list of items already added
to the Cart.
The Cart is a temporary list of products you’ve selected within the current session.
These are not automatically saved when you close the browser or select the start over
button.
Enough information is given to identify the products along with Metadata and Download
links.
Items can be removed from the cart individually with the Remove button or the entire cart
can be emptied by selecting Remove All.
Items in the Cart can be saved as a comma-separated value file on the desktop for use within the
download manager.
A link to the download manager is provided for convenience on the Cart page.
The National Map Download Manager will be discussed in a later lesson.
To save the contents of the cart to a CSV file click the “list and export cart items”
button.
The CSV file can also be read easily into Microsoft Excel, LibreOffice, or any other
spreadsheet program that reads CSV files, in addition to being used to import the products
into the National Map Download Manager.
In this lesson, we discussed how to download data using the National Map download client.
This concludes lesson 4b, to continue to the next lesson, please return to the course homepage.