Geoscientists and researchers actively study the world's many bodies of water to understand the physical, chemical, biological and geological aspects of the oceans and the impacts of environmental factors on topography.

Because oceans vary dramatically in depth and elevation, massive amounts of data on land elevation, ocean depth, contours and water properties must be collected and analyzed. These complex data require a robust software program that can quickly process and display the information in a meaningful and informative way. RSI's IDL software is proving to be the industry's most useful tool for doing so.

The Earth Sciences Department at Millersville University of Pennsylvania focuses on the study of oceanography, geology and meteorology. Professor Yin S. Soong, who specializes in the teaching and research of ocean circulations, oceanography data visualization and numerical modeling, is a long-time user of IDL for developing custom applications to efficiently handle ocean topography.

The Challenge of Complex Data Sets Leads to IDL
Soong's ocean data comes largely from federal government laboratories and includes a range of data types such as earth surface elevation, seawater properties, and satellite remote sensing data. These data files range in size from 10 to 30 megabytes. Soong's biggest challenge has been displaying and analyzing the large, complex data sets in an easy-to-use graphical user interface (GUI). After experimenting unsuccessfully with programs such as FORTRAN, VisualBasic, QuickBasic and various spreadsheet programs, Soong turned to IDL.

"There is no other computer language or existing software that let's me do what I want to do: interactively display and analyze oceanography data on different operating systems," stated Soong. "I selected IDL for its array-oriented design, robust GUI, versatile procedures, and object-oriented programming features. IDL is an effective tool for freshman students and professionals alike," he added.

Development Time Reduced by Ten Months
In terms of the timesavings Soong has achieved as a result of using IDL, the numbers speak for themselves. "I estimate I've saved at least ten months of development time by using IDL over another program such as Visual Basic," he stated.

World Topography Viewer
Using IDL as the programming language, Soong developed the World Topography Viewer. The multi-faceted applications of the World Topography Viewer allow geoscientists to:

• View any elevation point on Earth
• Plot elevation profiles around the world at any latitude or longitude or between any two arbitrary points
• View topographic animations of a rotating Earth
• View 3D images or contours
• View topographic animations of a rotating Earth

To develop the World Topography Viewer, Soong used a variety of IDL routines, primarily widgets, plots and contour routines. According to Soong, "The ease of manipulating multidimensional data and the robust GUI," are IDL's best features.