The ground beneath our feet, our cars, our buildings, appears to be incredibly solid. But, rarely, that solid ground can simply open up without warning, dropping whatever was above into an unpredictably deep.hole. Sinkholes can be anywhere from a few feet wide and deep, to two thousand feet in diameter and depth. An undiscovered cavern or deep mine can collapse, allowing the ground above to crater, or a broken water main or heavy storm can erode a hole from below, until the surface becomes a thin shell that collapses at once. Communities built atop karst formations are very susceptible, where a layer of bedrock is water-soluble, like limestone, and natural processes can wear away caves and fissures, weakening support of the ground above. Gathered here are images of some of these sinkholes, both man-made and natural, around the world
Lightning, one of the most beautiful displays in nature. It is also one of the most deadly natural phenomena known to man. With bolt temperatures hotter than the surface of the sun and shockwaves beaming out in all directions, lightning is a lesson in physical science and humility.
Lightning is a massive electrostatic discharge between electrically charged regions within clouds, or between a cloud and the Earth's surface. The charged regions within the atmosphere temporarily equalize themselves through a lightning flash, commonly referred to as a strike if it hits an object on the ground. There are three primary types; from a cloud to itself (intra-cloud or IC); from one cloud to another cloud (CC) and finally between a cloud and the ground (CG). Although lightning is always accompanied by the sound of thunder, distant lightning may be seen but be too far away for the thunder to be heard. Lightning occurs approximately 40–50 times a second worldwide, resulting in nearly 1.4 billion flashes per year.
May 20 2013, a monster tornado struck Moore, Oklahoma, near Oklahoma City. The twister, with winds of at least 200 mph, traveled for 20 miles, leaving a two-mile-wide path of destruction, flattening homes, smashing vehicles, and killing at least 24 people, including nine children.
Those who want to come to the exclusion zone of Chernobyl have to file documents for a permit two weeks before their visit. Then they are instructed at the checkpoint: visitors are not allowed to smoke, eat in the open air, take any plants or items away from the zone, drink water from the wells, rivers or any other ground sources. Body should be covered with clothes leaving as few exposed areas as possible.
Before 1995, the small Caribbean island of Montserrat was a relatively quiet tourist destination -- a British Overseas Territory with a population of 11,000. Then, the Soufriere Hills volcano came to life after remaining quiet since the 17th century. Thousands lived in the direct path of ensuing mudflows and pyroclastic flows -- cascades of hot gas and rock. The capital city of Plymouth and 20 other settlements were completely destroyed. Dozens lost their lives initially, and thousands were evacuated as eruptions continued off and on for years afterward. More than 7,000 residents moved away, and tourist dollars vanished. While the volcano is still active, it has been relatively quiet since early 2010, and nearly half of the island remains a designated exclusion zone.
Hydroelectric power stations are typically located near water sources, or on the source itself, such as dams on rivers. But Taum Sauk Hydroelectric Power Station is located more than 80 kilometers from the nearest water source – the Mississippi river. Built on top of the mountainous St. Francois region of the Missouri Ozarks, approximately 140 km south of St. Louis near Lesterville, Missouri, the Taum Sauk Hydroelectric Power Station is a pure pumped-storage hydroelectric plant, designed to help meet peak power demands during the day. During periods of high electrical demand, water stored in a kidney-shaped reservoir on top of Proffit Mountain is released through turbines into a lower reservoir, two kilometers away, on the East Fork of the Black River. At night, when electrical demand is low, the excess electricity available on the power grid is used to pump water back to the mountaintop. In essence, the power plant functions like a huge battery, storing excess power until it is needed.