[...]... INTRODUCTION The Encyclopedia of Earth Science is intended to provide a broad view of some of the most important subjects in the field of earth sciences The topics covered in the encyclopedia include longer entries on the many broad subdisciplines in the earth sciences (hydrology, structural geology, petrology, isotope geology, geochemistry, geomorphology, atmospheric sciences, climate, and oceanography),... their science AGU now stands as a leader in the increasingly interdisciplinary global endeavor that encompasses the geophysical sciences AGU’s activities are focused on the organization and dissemination of scientific information in the interdisciplinary and international field of geophysics The geophysical sciences involve four fundamental areas: atmospheric and ocean sciences; solid -Earth sciences;... in strengthening geoscience education and increasing public awareness of the vital role that geosciences play in society AGI supports its programs and initiatives through sales of its publications and services, royalties, contracts, grants, contributions, and affiliated society dues AGI’s staff provides professional and informational services related to government affairs; earth- science education, outreach,... The geophysical sciences involve four fundamental areas: atmospheric and ocean sciences; solid -Earth sciences; hydrologic sciences; and space sciences AGU has a broad range of publications and meetings and educational and other activities that support research in the Earth and space sciences American Meteorological Association (AMS) The American Meteorological Society (http://www.ametsoc.org) was founded... interest to society The work is extensively cross-referenced and indexed to facilitate locating topics of interest Entries in the Encyclopedia of Earth Science are based on extensive research and review of the scientific literature, ranging from the general science to very specialized fields Most of the entries include important scientific references and sources listed as “Further Reading” at the end... to the surface Pressure, including air pressure, is measured as the force divided by the area over which it acts The air pressure is greatest near the Earth s surface and decreases with height, because there is a greater number of air molecules near the Earth s surface (the air pressure represents the sum of the total mass of air above a certain point) A one-square-inch column of air extending from sea... thus telling the height of the object above the ground A laser altimeter can measure the distance from a spacecraft or satellite to a fixed position on Earth The measurement when compiled with radial orbit knowledge can provide the topography of the Earth Altiplano A large, uplifted plateau in the Bolivian and Peruvian Andes of South America The plateau has an area of about 65,536 square miles (170,000... events, the major periods of geological time, history, people who have made significant contributions to the field, technology and instruments, organizations, and other subjects The Encyclopedia of Earth Science is intended to be a reference for high school and college students, teachers and professors, scientists, librarians, journalists, general readers, and specialists looking for information outside... Implications.” Precambrian Research 86 (1997): 117–154 Rivers, Toby, and Dave Corrigan “Convergent Margin on Southeastern Laurentia during the Mesoproterozoic: Tectonic Implications.” Canadian Journal of Earth Sciences 37 (2000): 359–383 Rivers, Toby, J Martipole, Charles F Gower, and Anthony Davidson “New Tectonic Subdivisions of the Grenville province, Southeast Canadian Shield.” Tectonics 8 (1989): 63–84... a remarkable 10 billion collisions per second with other air molecules near the Earth s surface The density of air molecules is highest near the surface, decreases rapidly upward in the lower 62 miles (100 km) of the atmosphere, then decreases slowly upward to above 310 miles (500 km) Air molecules are pulled toward the Earth by gravity and are therefore more abundant closer to the surface Pressure, . encyclopedia of Earth Science