What was erupting in the year...?
There were 0 confirmed eruptions at some point during 2021 from 0 different volcanoes; 0 of those were new eruptions that started during the year. A stop date with "(continuing)" indicates that the eruption was considered to be ongoing as of the date indicated. Data is reported through the last data update (10 December 2020). Information about more recent eruptions can be found in the Smithsonian / USGS Weekly Volcanic Activity Report.
Eruption data is not yet available for 2021.
Global Volcanism Program, 2013. Volcanoes of the World, v. 4.9.2 (10 Dec 2020). Venzke, E (ed.). Smithsonian Institution. Downloaded 28 Jan 2021. https://doi.org/10.5479/si.GVP.VOTW4-2013.