Hazards & Disasters

From The Encyclopedia of Earth
(Redirected from Hazards & Disasters (main))
Jump to: navigation, search

Hazards and disasters describe a range of phenomena from those ascribed to nature, including hurricanes, tornados, earthquakes and volcanoes, to those in which both humans and nature share a role. This includes some episodes of natural flooding and wildfires to those purely of human origin like the chemical leak in Bhopal and theDeepwater Horizon (OCEAN OIL)oil spill (OCEAN OIL).

No matter the cause, human lives and well-being are often at risk in addition to large swaths of the natural environment. Hazards and disasters affect populations worldwide, regardless of politics, wealth, location or other factors which tend to differentiate populations

CurryTheLineStorm Smithsonian.gif.jpeg
Derecho (Hazards & Disasters) Two types of derecho may be distinguished based largely on the organization and behavior of the associated derecho-producing convective system. The type of derecho most often... More »

Wind turbine bat mortality Wind turbine bat mortality is a significant adverse impact of large scale wind energy development. Wind energy has become an increasingly important sector of the renewable... More »

Experts flickr hige-daruma.jpg
After Fukushima (Hazards & Disasters) SciDev.Net has produced a special Spotlight on "Nuclear Power After Fukushima" on 29 September 2011. SciDev.Net Spotlights are collections of feature, news and opinion... More »

Tsunami1 USGS.jpg
What is a Tsunami? What is a Tsunami? The phenomenon we call tsunami is a series of large waves of extremely long wavelength and period usually generated by a violent, impulsive undersea... More »

Tsunami3 NASA.jpg
How Do Earthquakes Generate Tsunamis? By far, the most destructive tsunamis are generated from large, shallow earthquakes with an epicenter or fault line near or on the ocean floor. These usually occur in... More »

MildewBob Blaylock.jpg
Dark side of insulation Building insulation has become a modish activity in the western world since the 1980s. Considerable benefits can accrue in energy conservation, occupant comfort and reduction of... More »

Earthquake-TsunamiComparison NASA.jpg
Tsunami Inundation Along Japan's Eastern Coast Tsunami Inundation Along Japan's Eastern Coast The extent of inundation from the destructive and deadly tsunami triggered by the March 11, 2011, magnitude 8.9 earthquake... More »

Branch in BeiChuan after earthquake.jpg
Earthquake (Hazards & Disasters) An earthquake is a sudden vibration or trembling in the Earth. More than 150,000 tremors strong enough to be felt by humans occur each year worldwide (see Chance of an... More »

AirPollution1 NSF-Z Li.jpg
Air pollution worsens drought and flooding Air Pollution a Culprit in Worsening Drought and Flooding Increases in aerosols can affect cloud development Increases in air pollution and other particulate matter... More »

Wind turbine bird mortality Wind turbine bird mortality is a by-product of large scale wind farms, which are increasingly promoted as an alternative to fossil fuel derived energy production. To adequately assess the extent of impact to avian populations, deeper factors than gross mortality by turbine action must be assessed. In particular, one must examine: (a) impacts to threatened bird species, (b) total impacts due to avian habitat loss as well as direct mechanicalkill, (c) ecological impacts due to apex predator bird loss and (d) future siting decisions for windfarms, since much of the prior bird mortality is due to poor siting decisions. Bird mortality from wind turbines is a significant adverse ecological impact, and threatens to expand in scope dramatically with the rush to develop new energy sources. This impact is measured as high due to the loss of threatened species and due to... More »

Grand Coulee Dam.jpg
Hydroelectricity (Hazards & Disasters) Hydroelectricity is electricity generated by converting the kinetic energy of falling or flowing water. It is considered the most widely installed form of renewable energy, although most large dams have a finite lifetime unless dredging of silt is periodically conducted. Hydroelectricity has and has a considerably lower output level of the greenhouse gas carbon dioxide than fossil fuel powered energy plants, and less life cycle greenhouse gas impact than solar power. Furthermore, the ecological impacts of hydropower is arguably greater than any form of energy production, due to the large footprint of biological impact of reservoirs and other needed developed areas. Worldwide, an installed capacity of 777 Gigawatts was catalogued in the year 2006, sufficient to supply one fifth of the world power supply. Since most of the prime locations for hydroelectric power have been tapped, the... More »

0106-aillinoiscarp-asian-carp-great-lakes-full full 600255b1255d.jpg
Asian Carp and the Great Lakes Region Alien species of Asian carp are a significant ongoing adverse ecological threat to the Great Lakes of North America. Chief pathways for the introduction of these species has been from the waterways of the city of Chicago, Illinois. The U.S. Congress and federal regulatory agencies are investigating protocols to reduce alien species influxes from Chicago waterways into the Great Lakes, whose fishery value is approximately seven billion dollars per annum. The city of Chicago has resisted environmental protection initiatives, on the grounds that the city's commercial interests may be harmed. Four species of non-indigenous Asian carp are expanding their range in U.S. waterways, resulting in a variety of concerns and problems. Three species—bighead, silver, and black carp—are of particular note, based on the perceived degree of environmental concern. Current controversy... More »

Branch in BeiChuan after earthquake.jpg
Earthquake (Hazards & Disasters) An earthquake is a sudden vibration or trembling in the Earth. More than 150,000 tremors strong enough to be felt by humans occur each year worldwide (see Chance of an Earthquake). Earthquake motion is caused by the quick release of stored potential energy into the kinetic energy of motion. Most earthquakes are produced along faults, tectonic plate boundary zones, or along the mid-oceanic ridges (Figures 1 and 2). At these areas, large masses of rock that are moving past each other can become locked due to friction. Friction is overcome when the accumulating stress has enough force to cause a sudden slippage of the rock masses. The magnitude of the shock wave released into the surrounding rocks is controlled by the quantity of stress built up because of friction, the distance the rock moved when the slippage occurred, and ability of the... More »

Accidental release source terms Accidental release source terms are the mathematical equations that quantify the flow rate at which accidental releases of air pollutants into the ambient environment can occur at industrial facilities such as petroleum refineries, natural gas processing plants, petrochemical and chemical plants, oil and gas transportation pipelines, and many other industrial facilities. Accidental releases in such facilities may occur through acts of nature (e.g., floods, hurricanes or earthquakes), operational errors, faulty design or inadequate maintenance. Governmental regulations in a many countries require that the probability of such accidental releases be analyzed and their quantitative impact upon the environment and human health be determined so that mitigating steps can be planned and implemented. There are a number of mathematical calculation methods for determining the flow rate... More »