A joint mission between NASA and the Indian Space Research Organisation (ISRO), the NISAR satellite, was successfully launched on July 30, 2025. This advanced Earth-observing satellite is equipped with dual-frequency radar systems designed to monitor changes on Earth's surface with remarkable precision, down to one centimeter. A primary focus of NISAR's mission is to study the cryosphere, with a significant emphasis on monitoring the motion and melting of Antarctica's vast ice sheets.
The NISAR satellite's Sun-synchronous orbit is configured to maximize its coverage of the polar regions, enabling detailed research into the Antarctic ice. The data gathered will be crucial for understanding the complex processes driving ice sheet motion and melting, providing critical insights into the accelerating rate of global sea-level rise. Scientists anticipate that the data will help decipher how small-scale processes can lead to monumental changes in these massive ice formations. The Antarctic ice sheet alone contains enough ice to raise global sea levels by approximately 58 meters if it were to melt entirely, with an average annual loss of about 150 billion metric tons of ice. This international partnership is committed to making all NISAR data freely accessible to researchers worldwide.
The satellite's dual-radar payload features an L-band system from NASA and an S-band system from ISRO. The L-band radar, with its longer wavelength, can penetrate deeper into ice sheets, which is ideal for studying glacial movement, while the S-band radar focuses on finer surface details. This dual approach ensures a more complete picture of ice dynamics. The insights from NISAR are vital as Antarctica's ice sheets are a significant contributor to global sea-level rise. Studies indicate that if current emission levels continue, Antarctica's ice melt could lead to catastrophic sea-level increases beyond the 21st century, with potential for rapid glacier retreat and even the near-total collapse of the ice sheet by 2300 under high-emission scenarios. The mission's ability to provide a consistent, time-lapse view of ice motion will be key to improving future predictions and informing strategies to mitigate the impacts of rising sea levels, which already threaten coastal communities globally with saltwater intrusion and displacement.