Tracking Ice Flow in Two Greenland Outlet Glaciers Michael Jefferson Jr. Elizabeth City State University Research & Discover Summer 2010 Mentor: Mark Fahnestock Michael Jefferson Jr. Elizabeth City State University Research & Discover Summer 2010 Mentor: Mark Fahnestock

Objectives To identify the best pairs of files to investigate ice flow –There has to be a pair of images in order to see a change in the data Create a new program to process the images Gather the images and process them with the appropriate parameters Compare findings from each of the processed image pairs To identify the best pairs of files to investigate ice flow –There has to be a pair of images in order to see a change in the data Create a new program to process the images Gather the images and process them with the appropriate parameters Compare findings from each of the processed image pairs

Glaciers and Remote Sensing The Landsat 7 satellite orbits the earth and takes pictures of earth’s features The data collected by this satellite was used in my research The Landsat 7 satellite orbits the earth and takes pictures of earth’s features The data collected by this satellite was used in my research

Location Latitude(62.4), Longitude(-49.6) Kangiata Nunata Sermia( KNS)

Location Nunatakavsaup Sermia( NKS) Latitude(74.6),Longitude( -56.0) The distance was 1300 km between the two glaciers

NKS

Selecting Image files Files where downloaded from the United States Geological Survey (USGS) GLObal VISsualization Viewer (GLOVIS) website There were many images with too much cloud cover –If clouds cover features then the changes can not be tracked 2004, 2005, 2007 used for KNS 2001, 2002, 2005, 2010 used for NKS Files where downloaded from the United States Geological Survey (USGS) GLObal VISsualization Viewer (GLOVIS) website There were many images with too much cloud cover –If clouds cover features then the changes can not be tracked 2004, 2005, 2007 used for KNS 2001, 2002, 2005, 2010 used for NKS

The Program To track features a program was used –The idea of tracking glaciers through pairs of images was developed 20 years ago Dr. Bob Bindschalder and Dr. Ted Scambos Dr. Mark Fahnestock wrote the program –Restrictions: Only output the changes for one iteration over a single image To track features a program was used –The idea of tracking glaciers through pairs of images was developed 20 years ago Dr. Bob Bindschalder and Dr. Ted Scambos Dr. Mark Fahnestock wrote the program –Restrictions: Only output the changes for one iteration over a single image

The Program(Cont’d) The program works by reading a line from a.txt file –A text file includes the two images and the geographic locations where the moving should be present The program works by reading a line from a.txt file –A text file includes the two images and the geographic locations where the moving should be present

The Program cont’d srcimgdel: 10 destimgdel: 25 Source 20x20 Destination 50x50

Program Iteration Example of a single point of an iteration Describes the correlation over the source and destination The closer to the color red means the more “good” unique points Example of a single point of an iteration Describes the correlation over the source and destination The closer to the color red means the more “good” unique points

Creating a New Program The previous program only ran one set of iterations per image Not all sections of the image had distinct features Not all images were 100% cloud free A new program was created to display more than one iteration on a single image The previous program only ran one set of iterations per image Not all sections of the image had distinct features Not all images were 100% cloud free A new program was created to display more than one iteration on a single image Pic of one iteration

New Program: Multi-Velocity Display multiple iterations with different parameters Display the average velocity of the “good points” Good points were the iteration points that had a unique correlation surface values over a specified amount Display multiple iterations with different parameters Display the average velocity of the “good points” Good points were the iteration points that had a unique correlation surface values over a specified amount

Output from New Program Green Plus- Best Correlation Red Hexagon - Worst Correlation

Mapping Changes

Results for NKS This line represents the beginning of the comparable data

In years there was a large Ice front retreat this is what drove the large change in velocity over the years Figure by: Ryan Cassotto

Results for KNS Around 1 to 1.5 Km from the ice front my data was approximately the same through the years

Conclusion There was a large change in velocity in the northern glacier NKS during the years of There was no apparent changes in the southernmost glacier KNS There was a large change in velocity in the northern glacier NKS during the years of There was no apparent changes in the southernmost glacier KNS

Future Work Research more glaciers to investigate more velocity changes using satellite data Change the program to be more efficient to run on larger collections of data Research more glaciers to investigate more velocity changes using satellite data Change the program to be more efficient to run on larger collections of data

Acknowledgements Dr. George Hurtt(Research & Discover) Dr. Mark Fahnestock (UNH Researcher) USGS GLOVIS (Image Database) Ryan Cassotto(Graduate Student) Stephen Hale(UNH Professor) Dr. George Hurtt(Research & Discover) Dr. Mark Fahnestock (UNH Researcher) USGS GLOVIS (Image Database) Ryan Cassotto(Graduate Student) Stephen Hale(UNH Professor)

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