https://www.npr.org/2022/08/03/1115378385/tonga-volcano-stratosphere-water-warming
Tonga's volcano sent tons of water into the stratosphere. That could warm the Earth
Earlier large volcanic eruptions have affected climate, but they usually cool temperatures, because they send light-scattering aerosols into the stratosphere. Those aerosols act as a sort of massive layer of sunscreen. But since water vapor traps heat, the Tongan eruption could temporarily raise temperatures a bit, the researchers said.
It normally takes around 2-3 years for sulfate aerosols from volcanoes to fall out of the stratosphere. But the water from the Jan. 15 eruption could take 5-10 years to fully dissipate.