Volcanoes that are going to erupt will produce different gases, some of which are very smelly. There may also be earthquakes in the area. Some of the volcanoes even change shape — like the "bulge" of Mount St. Helens that moved toward Seattle at about four meters per day before that erupted in 1980. Not all volcanoes explode out of the top. Some grow a bulge in the side and the pressure builds up there and the volcano explodes sideways.
Forecasting volcanoes is still very hard though and will only get better the more people study what happens just before volcanoes erupt. Studying volcanoes can mean getting very close to them. This is highly dangerous because of the danger of explosion and also because it is very hot. Scientists studying Mount Etna are exposed to temperatures as high as 1000o C.
Scientists also have accurate sensors that pick up even the smallest vibrations and they monitor seismic activity constantly in an effort to predict as many volcanoes and Earthquakes as possible. However, some events, such as the tsunami on December 26 2004 are still a complete and tragic surprise.
Forecasting volcanoes is still very hard though and will only get better the more people study what happens just before volcanoes erupt. Studying volcanoes can mean getting very close to them. This is highly dangerous because of the danger of explosion and also because it is very hot. Scientists studying Mount Etna are exposed to temperatures as high as 1000o C.
Scientists also have accurate sensors that pick up even the smallest vibrations and they monitor seismic activity constantly in an effort to predict as many volcanoes and Earthquakes as possible. However, some events, such as the tsunami on December 26 2004 are still a complete and tragic surprise.