JPL
Careers
Education
Science & Technology
JPL Logo
JPL Logo
Image

Deep Ocean Tsunami Waves off the Sri Lankan Coast

Jan 26, 2005
The initial tsunami waves resulting from the undersea earthquake that occurred at 00:58:53 UTC (Coordinated Universal Time) on 26 December 2004 off the island of Sumatra, Indonesia, as seen by NASA's Terra spacecraft.

The initial tsunami waves resulting from the undersea earthquake that occurred at 00:58:53 UTC (Coordinated Universal Time) on 26 December 2004 off the island of Sumatra, Indonesia, took a little over 2 hours to reach the teardrop-shaped island of Sri Lanka. Additional waves continued to arrive for many hours afterward. At approximately 05:15 UTC, as NASA's Terra satellite passed overhead, the Multi-angle Imaging SpectroRadiometer (MISR) captured this image of deep ocean tsunami waves about 30-40 kilometers from Sri Lanka's southwestern coast. The waves are made visible due to the effects of changes in sea-surface slope on the reflected sunglint pattern, shown here in MISR's 46° forward-pointing camera. Sunglint occurs when sunlight reflects off a water surface in much the same way light reflects off a mirror, and the position of the Sun, angle of observation, and orientation of the sea surface determines how bright each part of the ocean appears in the image. These large wave features were invisible to MISR's nadir (vertical-viewing) camera. The image covers an area of 208 kilometers x 207 kilometers.

Since the greatest impact of the tsunami was generally in an east-west direction, the havoc caused by the tsunami along the southwestern shores of Sri Lanka was not as severe as along the eastern coast, though there was still substantial damage in this region--as evidenced by the brownish debris in the water--because tsunami waves can diffract around land masses. The ripple-like wave pattern evident in this MISR image roughly correlates with the undersea boundary of the continental shelf. This surface manifestation is likely to be caused by interaction of deep waves with the ocean floor, rather than by the more usually-observed surface waves driven by winds. It is possible that this semi-concentric pattern represents wave reflection from the continental land mass; however, a combination of wave modeling and detailed bathymetric data is required to fully understand the dynamics. Examination of other MISR images of this area, taken under similar illumination conditions, has not uncovered any surface patterns resembling those seen here.

This image is an example of how MISR's multiangular capability provides unique information for understanding how tsunamis propagate. Another application of MISR data enabled measuring the motion of breaking tsunami waves along the eastern shores of Andhra Pradesh, India.

The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82° north and 82° south latitude. These data products were generated from a portion of the imagery acquired during Terra orbit 26720 and utilize data from within blocks 85 to 86 within World Reference System-2 path 142.

MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.

Download JPG
Download TIFF
Target
  • Earth
Spacecraft
  • Terra
Instrument
  • Multi-angle Imaging SpectroRadiometer (MISR)
Credit
NASA/GSFC/LaRC/JPL, MISR Team.

Keep Exploring

Related Topic

News .

NASA-Built Instrument Will Help to Spot Greenhouse Gas Super-Emitters

News .

NASA Satellites Detect Signs of Volcanic Unrest Years Before Eruptions

News .

POINTER: Seeing Through Walls to Help Locate Firefighters

News .

After COVID-19 Delay, Delta-X Field Campaign Begins in Louisiana

News .

NASA Analysis: Earth Is Safe From Asteroid Apophis for 100-Plus Years

News .

Major Earth Satellite to Track Disasters, Effects of Climate Change

Topic .

Earth

News .

Asteroid 2001 FO32 Will Safely Pass by Earth March 21

News .

NASA Data Powers New USDA Soil Moisture Portal

News .

A Pioneering NASA Mini Weather Satellite Ends Its Mission

About JPL
Who We Are
Executive Council
Directors of JPL
JPL History
Documentary Series
Virtual Tour
Annual Reports
Missions
All
Current
Past
Future
News
All
Earth
Mars
Solar System
Universe
Technology
Galleries
Images
Videos
Audio
Podcasts
Infographics
Visions of the Future
Slice of History
Engage
JPL and the Community
Lecture Series
Public Tours
Events
Team Competitions
JPL Speakers Bureau
Topics
Solar System
Mars
Earth
Climate Change
Stars and Galaxies
Exoplanets
Technology
JPL Life
For Media
Contacts and Information
Press Kits
More
Asteroid Watch
Robotics at JPL
Subscribe to Newsletter
Universe Newsletter
Social Media
RSS
Get the Latest from JPL
Follow Us

JPL is a federally funded research and development center managed for NASA by Caltech.

More from JPL
Careers Education Science & Technology Acquisitions JPL Store
Careers
Education
Science & Technology
Acquisitions
JPL Store
Related NASA Sites
Basics of Spaceflight
Climate Kids
Earth / Global Climate Change
Exoplanet Exploration
Mars Exploration
Solar System Exploration
Space Place
NASA's Eyes Visualization Project
Voyager Interstellar Mission
NASA
Caltech
Privacy
Image Policy
FAQ
Feedback
Site Manager: Veronica McGregor
Site Editors: Tony Greicius, Randal Jackson, Naomi Hartono