The USGS provides science about natural hazards that threaten lives and livelihoods; the water, energy, minerals, and other natural resources we rely on; the health of our ecosystems and environment; and the impacts of climate and land-use change. Our scientists develop new methods and tools to supply timely, relevant, and useful information about the Earth and its processes. Learn more below.
Science Topics
FAQs
What gases are emitted by Kīlauea and other active volcanoes?
Ninety-nine percent of the gas molecules emitted during a volcanic eruption are water vapor (H2O), carbon dioxide (CO2), and sulfur dioxide (SO2). The remaining one percent is comprised of small amounts of hydrogen sulfide, carbon monoxide, hydrogen chloride, hydrogen fluoride, and other minor gas species. Learn more: Volcanic gases can be harmful to health, vegetation and infrastructure
Who monitors volcanic gases emitted by Kīlauea and how is it done?
The U.S. Geological Survey's Hawaiian Volcano Observatory (HVO) determines the amount and composition of gases emitted by Kīlauea Volcano. Changes in gas emissions can reveal important clues about the inner workings of a volcano, so they are measured on a regular basis. HVO scientists use both remote and direct sampling techniques to measure compositions and emission rates of gas from Kīlauea...
Does vog (volcanic smog) impact plants and animals?
The sulfuric acid droplets in vog have the corrosive properties of dilute battery acid. When vog mixes directly with moisture on the leaves of plants it can cause severe chemical burns, which can damage or kill the plants. Sulfur dioxide (SO2) gas can also diffuse through leaves and dissolve to form acidic conditions within plant tissue. Farmers on Hawai`i Island, particularly in the Ka`u District...
Education
Our Water Our Lives: Floods
This Teacher Guide includes background information, lesson plans, and examples of student answers for four lessons about floods. The Student Worksheet includes student activities and questions. This can be downloaded and printed or transferred to a digital classroom document.
Our Water, Our Lives: California
This Teacher Guide includes background information, lesson plans, and examples of student answers for four lessons about water resources in California. The Student Worksheet includes student activities and questions. It can be downloaded and printed or transferred to a digital classroom document.
Our Water, Our Lives: The Chesapeake Bay Watershed
This Teacher Guide includes background information, lesson plans, and examples of student answers for three lessons about the Chesapeake Bay watershed. The Student Worksheet includes student activities and questions. This can be downloaded and printed or transferred to a digital classroom document.