Overall there are 45 volcanoes with continuing eruptions as of the Stop Dates indicated, and as reported through the last data update (12 March 2021), sorted with the most recently started eruption at the top.

Fast-moving lava can kill people and falling ash can make it hard for them to breathe. They can also die from famine, fires and earthquakes which can be related to volcanoes. People can lose their possessions as volcanoes can destroy houses, roads and fields. Lava can kill plants and animals too.

But they can also have advantages: – Volcanic ash contains many minerals which make the soil very fertile, – the earth’s crust around a volcano is so thin that it easy to win energy from the heat of the earth, – and volcanoes attract tourists.

According to the catalog “Volcanoes of the World” by Smithsonian Institution volcanologists Tom Simkin and Lee Siebert, 9 percent of eruptions end in less than one day, 16 percent within two days, 24 percent within one week, 30 percent within two weeks, 43 percent within a month, 53 percent within two months, 83 …

An increase in the frequency and intensity of felt earthquakes. Noticeable steaming or fumarolic activity and new or enlarged areas of hot ground. Subtle swelling of the ground surface. Small changes in heat flow.

There is no way to stop the flow of lava, scientists say. Many have tried in the past, including famed U.S. Gen. Patton, who attempted to bomb lava in its tracks. According to the U.S. Geological Survey, Patton was a lieutenant colonel in 1935 when another volcanic eruption on Hawaii’s Big Island threatened Hilo.

Those parts of the surrounding states of Montana, Idaho, and Wyoming that are closest to Yellowstone would be affected by pyroclastic flows, while other places in the United States would be impacted by falling ash (the amount of ash would decrease with distance from the eruption site).