Dictionary

• acceleration of gravity. the gravitational acceleration of a freely falling object, expressed in terms of the rate of increase of velocity per second: on earth 980.665 cm (32.l7 ft.) per second per second is the standard
• avalanche. a mass of loosened snow, earth, rocks, etc. suddenly and swiftly sliding down a mountain, often growing as it descends
• basalt. a dark, tough, fine-grained to dense, extrusive volcanic rock commonly occurring in sheetlike lava flows
• black spots. dots on the Sun generating a lot of energy considered to warm climate and cause El nino
• blizzard. a severe snowstorm characterized by cold temperatures and heavy drifting of snow
• caldera. large, basinlike depression formed by the collapse of an overlying volcanic cone.
• Cartesian coordinates. a pair of numbers that locate a point in a plane by its distances from two fixed, intersecting, usually perpendicular lines in the same plane
• cinder cone volcano. Conical, usually highly symmetrical hill of pyroplastics.
• concave. hollow and curved like the inside of a bowl
• conical. resembling or shaped like a cone
• crater. Depression resulting from volcanic collapse or violent explosion, or by gradual erosion.
• crust. the solid, rocky outer portion or shell of the earth; lithosphere
• dike or dike swarms. tabular body or bodies of molten rock injected into a fissure.
• drought. a prolonged period of dry weather; lack of rain
• earthquake. a shaking or trembling of the crust of the earth, caused by underground volcanic forces or by breaking and shifting of rock beneath the surface
• El-nino. a warm inshore current annually flowing south along the coast of Ecuador and, about every seven to ten years, extending down the coast of Peru, where it has a devastating effect (El Nino Effect) on weather, crops, fish, etc.
• ENSO El nino Southern Oscillation
• ITCZ Inter Tropical Convergence Zone
• lahar. debris flows of volcanic materials that often accompany or follow a volcanic eruption.
• lava. fluid rock that issues from a volcano or fissure and is composed primarily of basalt, andesite, or rhyolite rock.
• leyden jar. a condenser for static electricity, consisting of a glass jar with a coat of tinfoil outside and inside and a metal rod connecting with the inner lining and passing through the lid
• lightning. a flash of light in the sky caused by the discharge of atmospheric electricity from one cloud to another or between a cloud and the earth
• magma. molten rock within the Earth.
• mantle. layer of the earth's interior between the crust and the core
• molten. melted or liquefied by heat
• mudflow. a massive movement of wet soil, rocks
• pilot streamer. charged particle send from the cloud seeking shortest distance for a lightning between ground and the cloud
• plate tectonics. the theory that the earth's surface consists of plates, or large crustal slabs, whose constant motion explains continental drift, mountain building, etc
• pyroclastics (tephra). various-sized particles ejected by volcanic activity.
• shield volcano. low, broad-profile volcano built up by outpourings of highly fluid basaltic lava.
• SO Southern Oscillation
• stratovolcano (composite volcano). cone constructed by alternating layers of lava and
• pyroclastic material. debris comming out of a volcano during an explosion
• subduction. the sinking of one crustal plate under another as they collide
• thunderstorm. storm accompanied by thunder and lightning
• vent. an opening in the Earth's surface through which gas or lava can escape.
• volcanology. study of volcanos
• wavelength. the distance, measured in the direction of progression of a wave, from any given point to the next point characterized by the same phase
• wave period. time between two successive waves