Graphical Ice Sheet Analyzer

• Main Authors: Otto, C.D., Anderson, D., Jezek, K.C.
• Format: Report
• Language: English
• Published: Byrd Polar Research Center, The Ohio State University. 1994
• Subjects: Graphical Ice Sheet Analysis (GISA) program; Time series animation; Ice sheets; Passive microwave data sets; Greenland; Antarc*; Antarctica; Ice Sheet; Polar Research; Sea ice
• Online Access: http://hdl.handle.net/1811/51324

During the past decade, long time series of passive microwave data sets have become available over the polar regions. These data sets can be used to study important glacial, atmospheric and oceanic processes. However, the data volume is large and the data area is extensive, requiring researchers to develop methods that enable easy manipulation and visualization of these data sets. Further more, a key attribute of these data sets is their sequential format, which can be used to develop unique intuitions about changes in the dynamical processes with time. To inspect the data over Greenland and Antarctica, and to retain the basic temporal information provided by the passive microwave data, a tool was developed to create images of consecutive days of data and combine them to form animations. To help visualize the glaciologic aspects of the data, the images in the animations consist of two distinctive data sets; a Digital Elevation Model and Passive Microwave Data, which are co-registered to provide a 3D image. Initially, Special Sensor Microwave / Imager 37v brightness temperatures were used to create the animations. These SSM/I brightness temperatures have allowed researchers to identify four polar processes in the animations; surface melting, sea ice coverage, temperature variances, and weather fronts and patterns. Analyzing these processes is aided by the animations because they allow researchers to see spacial and temporal interactions. The weather patterns, in particular, influence the surface melting on the ice sheets. The seasonal ebb and flow of the sea ice is a dramatic event that can span millions of square kilometers in only a few months. The imagery data sets are not solely limited to SSM/I data. Any data in standard byte image format can be viewed. Several secondary programs have been created along with the main software package that allow for conversion of data to this format.