A geologist is a scientist who studies the solid and liquid matter that constitutes the Earth as well as the processes that shape it. Geologists usually study geology, although backgrounds in physics, chemistry, biology, and other sciences are also useful. Field work is an important component of geology, although many subdisciplines incorporate laboratory work. Some geologists work in the mining business searching for metals, oils, and other Earth resources. They are also in the forefront of natural hazards and disasters prevention and mitigation, studying natural hazards such as earthquakes, volcanic activity, tsunamis, weather storms. Their studies are used to warn the general public of the occurrence of these events. Geologists are also important contributors to climate change discussions.