As a result of many small earthquakes in February 2021 on the Icelandic Peninsula Reykjanes, experts warned that magma was moving under the Geldingadalur Valley and could soon erupt. The eruption officially began in the late evening of March 19 when lava broke through the surface near Fagradalsfjalla, one of several shield volcanoes on the peninsula.
Although the event was small compared to other recent eruptions in Iceland, it was bright and large enough to be observed by NASA and NOAA satellites – the US National Oceanic and Atmospheric Administration. On March 21, 2021, the Suomi NPP satellite received a night view of the west of Iceland through a thin layer of clouds. Reykjavik, Reykjanesber and other cities appear as bright spots in the image. The eruption looks like a new spot of light in the southwestern part of the island. For comparison, the image on the left shows the same area a few days before the eruption.
The images were captured day-night with the Visible Infrared Imaging Radiometer (VIIRS) suite, which detects light in the green to near infrared wavelength range and uses filtering techniques to observe weak signals such as fires, electric lights, etc. and the glow emitted by lava. During the day, the Moderate Resolution Spectroradiometer (MODIS) acquired natural and false color images as the eruptions erupted slightly brightened the clouds in the area.
Lava poured out of a crack that was originally 500 to 700 m long. Except for crowds of spectators and a possible archaeological site, lava has not yet threatened anyone. Ash or gas emissions were also not a problem. However, the Icelandic Meteorological Office monitors the volcano and shares the results of the forecast model.