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See also: NCEI Data Certification

What is data certification and is it necessary?

Most U.S. state courts require records that are submitted as evidence in a court of law to be authenticated, or certified. NCEI offers data certification, but only certain products are eligible (see What data can be certified?).  

What data can be certified?

Some data are eligible for certification, such as PDF output, for specific datasets. Find the order you want to certify via Check Order Status, and wait for our response.


What is a dataset?

A dataset is a collection or group of scientific data or information. Datasets contain files or individual items.

Where is the dataset documentation?

Each dataset provides documentation. Go to: View Dataset Details > Downloads > Documentation. Note: documentation included in an order is a condensed version.

What is the Available Only checkbox?

Not all datasets are searchable through this tool at this time. “Available Only” is selected by default to limit the search for available data. Deselect “Available Only” to view all datasets, including details and alternate access links.


How do I search for datasets?

Go to Dataset Search to view and search for datasets. Use the search inputs at the top of the page to narrow results by What, Where and When (see explanations below).

How do I search for data?

Each dataset (see How do I search for datasets?) includes a “Search Within This Dataset” button, which lists data files. Use the search inputs at the top of the page to narrow results. Files include period of record, file size, data types, stations, and other details.

What is meant by What, Where, When?

Data vary in domain, purpose, and use, yet most data have three things in common: what it is, where it is, and when the observation occurred. Use these three search parameters to find data.

How do I use the What search input?

“What” finds what kind of data you are looking for. If searching for data relating to precipitation, type “precipitation” in the “What” search input to filter results based on that keyword.

How do I use the Where search input?

Start typing the location into the “Where” search input to autocomplete suggestions. Each suggestion searches for datasets/data that overlap with that location.

The “Find Location Using Map” button displays a map that allows you to draw a box around your interested location. To draw a box, click on the map and a red box will appear. Use the corner squares to adjust the box size. The “x” on the left clears the box. The “[/]” button activates the “click and drag” mode. Text boxes below the map represent North, West, South, and East coordinates and can be manually entered or modified.

How do I use the When search input?

The “When” search includes three parameters: year (YYYY), month (MM), and day (DD). Type the date or use the up/down arrows. Searches default to one day. “Select Date Range/Single Date” is used for multiple days.

How do I reset / clear a search?

Gray blocks appear below each search box to indicate your search criteria/filter. To remove them, click on the “x”. To reset the search, remove all the gray blocks individually.

Can I bookmark / save a search?

Yes! The search parameters are included in the URL, so you may bookmark (or save/share) the search.

What are Observation Types?

Observation type describes how the data are collected. For example, data collected via satellites are “Satellite” observation types, while data collected via in situ weather stations (such as Global Summary of the Month) are “Land Surface” observation types. Observation Types are listed under Dataset Details > Metadata.

What are Keywords?

Keywords refer to the NASA Global Change Master Directory (GCMD) Science and Services Keywords. These keywords categorize individual data types into common terms. For example, Global Summary of the Year includes air temperature as the data type “TAVG”, and Global Hourly Data reports air temperature as the data type “TMP”. A keyword search of “air temperature” returns both datasets. Keywords are listed under Dataset Details > Metadata.

What are Data Types?

Data Type refers to a single type of observation, such as air temperature or precipitation. Each dataset includes a set of data types.

How do I search for a specific data type?

On both the dataset and data search pages, use the “What” search input for data types. Type datatype: into the search box to limit your results.

What are Formats?

On the Dataset Search page type format: to only see datasets which have that particular file format. Currently supported file formats are CSV, NetCDF, and PDF.

What is Bulk Download?

Occasionally, a "Bulk Download" link appears above the list of results. This link connects to NCEI’s publicly accessible FTP data server, where you can download files.

What does Select All do?

The orange “Select All” button adds all files to an order, which is the same as clicking “Select” on all results individually.

Why is Select All disabled / grayed out?

The “Select All” button is disabled or grayed out when the search results exceed the file count or file size order limits (see What are Order Limits?).

What does File Count/Limit and File Size/Limit, the text next to the Select All, mean?

The order, whether file size or file count, cannot exceed the given limit. If you exceed either limit, the “Select All” button is disabled or grayed out.

Why do no data exist for a specific location?

It could be that data in that location do not exist. If the results show that data exist for a particular location and dataset, but not for the data files (no results), this can occur with datasets such as Global-Marine, which report worldwide coverage, but only have data for oceans.


Are the data free?


How do I submit an order?

On the Data Search page (see How do I search for data?), choose files with the orange “Select” or “Select All” buttons. An orange bar will appear at the bottom of the screen with order limits. Select “Configure and Add”, modify options if desired, and then choose “Add Order to Cart”.

"Continue Browsing" to add orders to your cart, or "Proceed to Cart". Enter an email address and "Submit" the order. You will receive an email when the order is ready for download.

Small orders process faster, and multiple orders by a single customer are processed one at a time.

Can I download the data instead of submitting an order?

Yes! Go to: to browse and download data. Note: PDFs are unavailable when using this method.

If I can download the data, why place an order?

Placing an order allows you to select specific data options, such as date range and data types. It also allows you to obtain PDFs of data.

What are order limits?

Each dataset has an order limit for file size and file count, to reduce strain on NCEI resources. As you select files, an orange bar appears at the bottom of the screen with a file count and file size order limit. Exceeding either limit disables “Configure and Add”, preventing you to proceed with your order. If you exceed the limit, try using the bulk download link, when available.

How long does it take to fulfill my order?

Order processing varies; it can be instantaneous or require many days based on NCEI system load and order size. Small orders often complete quickly. You will receive an email when the order is ready, which will be available for 7 days.

How long do I have to download my order?

Once an order is ready, you have 7 days to download it.

Why aren’t my orders available to download indefinitely?

Orders are removed after 7 days due to limited server space. If your order was deleted before it was downloaded, please resubmit the order.

What are order options?

Order options define which data you want and how you want it. For example, if a dataset is available in multiple formats (e.g., CSV and PDF), there will be an order option for Format. Some options will disable others (e.g., selecting PDF will disable the data type as PDF includes data types), and some options will change the value.

How do I check my order status?

Go to Check Order Status, and enter your Order ID or email.

Access APIs

Here are links to help use NCEI's Access APIs to search and select data.

Customer Support

Call 1-828-271-4800 or email