NASA's SAGE III instrument on ISS sees aerosols and water vapor months after Tonga eruption

The Stratospheric Aerosol and Gas Experiment (SAGE) III instrument on the International Space Station (ISS), a third-generation instrument and a crucial element in NASA's climate observing system, continues to detect the enhanced aerosols and water vapour that belched into the stratosphere in January 2022 during the eruption of the Hunga Tonga-Hunga Ha'apai volcano.

According to NASA, aerosols from eruptions, and extreme wildfires, can remain in the stratosphere for months to years travelling around the globe, scattering light from the sun. Water vapour also continues to linger at high altitudes around the globe from the Tonga eruption and can remain in the atmosphere for several years.

Aerosols play an important role in Earth's climate. Increased stratospheric water vapour can not only lead to the destruction of Earth's sunscreen, stratospheric ozone, but because it is a greenhouse gas it warms the atmosphere. This offsets the cooling that occurs when stratospheric aerosol particles block sunlight by absorbing or scattering it, according to NASA.

Over 8 months after Hunga Tonga-Hunga Ha’apai erupted, the SAGEIII instrument on the @Space_Station is still detecting aerosols and water vapor belched into the stratosphere . 🌋 Learn more: https://t.co/H7G2rJi2CG pic.twitter.com/5pvt3Q39qN

— NASA Earth (@NASAEarth) September 21, 2022

"Capturing this stratospheric aerosol data over time is important because aerosols play a major role in determining the radiative and chemical balance of Earth's atmosphere,” noted Mahesh Kovilakam, SAGE III scientist and GloSSAC team member with SSAI, Inc. working at NASA Langley.

SAGE III was launched on February 19, 2017, from Kennedy Space Center in Florida and installed on the International Space Station during a 10-day robotic operation. Since 2017, the instrument has been measuring and collecting data on Earth's sunscreen, stratospheric ozone, as well as other gases and aerosols, through solar occultation, a process of observing the Sun rise and set through Earth's atmosphere.