CRONOS User Guide

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The CRONOS database is an online interface to weather and climate observations collected from automated sensors in North Carolina and surrounding states. The interface uses PHP to communicate with a MySQL database, and is designed to be dynamic and flexible. The target audience of users includes general public as well as advanced users such as researchers.

System Requirements

Web Browser
The CRONOS database requires a web browser. Recommended browsers are Microsoft Internet Explorer version 6 or later, Netscape version 7 or later, or Mozilla version 1.4 or later. Other browsers, such as Mac OSX’s Safari or Opera, have been tested by do not provide all the same functionalities.

Internet Access
Access to the CRONOS database is via the Internet and a web server located in the State Climate Office at NC State University. While high speed Internet access improves access to CRONOS features, it is not required.

Getting Started

CRONOS Main PagePoint your web browser to

Your screen should look like the one to the right:

The 3 options on the main CRONOS page are

Excel Spreadsheet of Stations – List of all stations, color-coded by station type. More details are below.

Interactive Map of Stations – Map of stations. Users can display all active stations in the CRONOS database, as well as current weather conditions, interstates, and rivers and streams. More information is below.

Data Retrieval – Form where users can pull recent hourly, daily or monthly observations where available.

Excel Spreadsheet of Stations

By choosing this option, users are presented with a list of all stations in the database with the following information for each station, as well as what parameters each station measures:


Interactive Map of Stations

By clicking on the map image on the main CRONOS page, you will see a map of North Carolina and the surrounding states displaying recent temperature observations by default. In the top-left of the map you will find a menu listing layers that can be turned on or off for the map display. Such layers include county boundaries, interstates, rivers and streams, as well as the various sites within the CRONOS database. A legend that depicts the currently displayed layers is located to the right of the map.


Data Retrieval

Data Retrieval Page

Once a station has been selected, users are presented with a screen that includes metadata, current conditions, and a list of measurements collected for that station. The list of measurements is station dependent - if the station does not measure a specific parameter, then it will not be listed on the page.

Users can retrieve hourly data for the most recent 7 days, daily observations for the past 180 days, and monthly data for the past 4 years. All data outside of these time frames would need to be directly requested from our office through our online data request form.

By checking the box beside a parameter, the user adds that parameter to the list of measurements to view. Users can also select the units they wish to use for many measurements. Once all desired parameters have been checked and units chosen, users should click “RETRIEVE DATA” to view the observations. Users have the option to view data as a web page (default option), an Excel spreadsheet, or as a delimited text file (comma or tab).

The web page output shows the observations selected, along with summaries of the data included at the bottom of the table.

In the header of each column, users can click on the GRAPH icon to view a graph of those observations over time. This is an especially useful feature for looking at general trends in the data.

NC CRONOS Database version 2.7.2