New Delhi: A recent analysis of data collected from the Surface Water and Ocean Topography (SWOT) satellite that was jointly developed by NASA and France’s CNES has provided remarkable details about a tsunami caused by a massive rockslide in the Dickson Fjord in Greenland in September 2023. An event that had never occurred before and lasted for nine days, caused vigorous shocks that reached every corner of the globe.
On September 16, 2023, more than 880 million cubic feet (25 million cubic metres) of rock and ice fell into the Dickson Fjord which is on the eastern coast of Greenland. The fjord is up to 1800 metres deep and 2.7 km wide, with walls rising over 1830 metres high. The subsequent tsunami moved back and forth within the steep walls of the fjord in a complex oscillatory pattern, with periods of 90 seconds for a week and was thus able to retain its energy because of minimal dissipation in the enclosed geography.
SWOT Satellite’s Unique Views
The SWOT satellite passed over the fjord on September 17, the water elevation data proved that there are disparities in the water height within the fjord. Both quantitative and qualitative results showed that some areas on the northern part of the fjord had water levels 1.2 metres higher than in the southern part. Josh Willis, who works at NASA’s Jet Propulsion Laboratory and specialises in sea level research, underlined the importance of this observation and highlighted that SWOT allowed us to gain an understanding of the wave’s shape that was impossible before.
Seismic Effect and Measurement Potential
Scientists have been able to follow seismological readings from this disaster, proving the reach of the tsunami. Even devices situated thousands of miles away recorded vibrations that resulted from the movement of the wave. Nadya Vinogradova Shiffer, a SWOT programme scientist at NASA, said that the satellite can be used for hazard surveillance and disaster risk reduction, suggesting a new paradigm of investigating such phenomena.
SWOT satellite was launched in December 2022 and uses Ka-band Radar Interferometer (KaRIn) to gauge water heights worldwide, including in such places as fjords. Its capacity to make minute observation within limited cover, as in the Dickson Fjord, is a major boost to satellite technology for environmental observation.
The SWOT mission is still actively gathering important information and increasing its knowledge of water behaviour and the effects of natural disasters in a shifting climate.
