Dynamic Drought Index for Basins in NC and SC
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  step1 Select time scale
  step2 Select drought index
  step3 Select display type


  step4 Map
  step5 Graph
  step6 Table

Selected variables:

- Monthly time scale
- Percentiles
> 100 % Monthly PDSI
- Map
> December 2017
> Quantile
> 5 classes
> Same class intervals

Dynamic Drought Index Maps

A web application for dynamic drought index maps in North and South Carolina has been developed as a web-based spatial decision support system for water resource planning and management. It consists of three parts: a numerical model for calculating percentiles of each drought index and performing spatial interpolation and averaging; a database storing the results from the numerical model, and a graphical user interface developed using Scalable Vector Graphics (SVG) with server-side scripting language PHP (PHP: Hypertext Preprocessor) and JavaScript. The graphical user interface provides user options for a selection of drought indices, their percentages for blending, and the classification method as well as resultant maps, graphs, and tables. It shows the advantages of flexibility in the interface.

Individual drought measures have been computed and interpolated at a 4 km resolution in North and South Carolina for the period January 1950 to present. Using this application the user can map or extract daily (for only KBDI), weekly, and monthly values for individual or blended drought indices. Since the indices are computed for point locations and then interpolated to a grid, the index values can be spatially aggregated based on the user specifications such as states, counties, climate divisions, 2-8 digit hydrologic units, and watersheds of interests.

Scalable Vector Graphics

The Scalable Vector Graphic (SVG) has recently gained lots of attention for web-based dynamic display of cartographic maps. The Scalable Vector Graphics (SVG) defines vector-based graphics in eXtensible Markup Language (XML) format for the web. It is a World Wide Web Consortium (W3C) recommendation and can be integrated with other W3C standards such as Document Object Model (DOM). DOM is a platform and language neutral Application Programming Interface (API) that allows programs to access and update the content, structure, and style of a document. The use of server side script language such as PHP and client side script language such as ECMAScript enables the communication between the database and SVG elements through the DOM.

This website is optimized for Microsoft Internet Explorer 5 and above. Adobe SVG viewer plugin is needed to see SVG maps and graphs. If you see a circle keeps changing its color below, you already have the plugin or you are using a browser with native SVG capabilities. If not, please download and install it (click the banner on the right). The use of Mozilla Firefox 1.5+ and Opera 9+ has been being tested. Download Adobe SVG Viewer

Let's start creating a dynamic drought index >> Go to step step1

Last modified: December 02, 2016
URI: http://www.dnr.sc.gov/drought/index.php
Direct any comments or questions to Jinyoung Rhee (rheej@sc.edu)