| Dyson\'s_Animated_Moon Interative moon map (Flash based) with brief information about various features. |
| Earth-Moon_Dynamics_Page Extracts from five papers studying Earth-Moon dynamics relating to evolution and gravity topics. |
| Geologic_Lunar_Research_Group Resource for all lunar observers interested in geologic, dome and TLP research. Some content in Italian. |
| Google_Moon A photographic map of the equatorial region with pan and zoom capability, showing locations of the Apollo landings. |
| Interactive_Map_of_the_Moon The visible and the hidden side. Includes games and basic information about the satellite and the lunar missions. |
| Keith\'s_Moon_Page A collection of facts, phases, folklore and photographs. |
| Lunar_Volcanoes An Introduction to Lunar Domes by Nigel Longshaw, an illustrated description of these features including characteristics and observation history. |
| Lunarsat_Info_Page Multimedia presentation of the European space mission to investigate the south pole for its suitability for the first permanent human outpost. |
| The_Moon_Illusion_Explained Why our satellite looks big at the horizon and smaller when higher up. |
| The_Moon_Museum A tour made on the 30th anniversary of the first lunar landing. |
| Moon_Page Some facts, quotations, trivia chosen at random. |
| Moon_Stereogram_Demonstration Demonstration as to why the Moon appears larger when nearer the horizon than when high in the sky. |
| Moon_Survey Tips for observing our satellite and drawing lunar features. Data archive, pictures, movies and selected links also available. |
| MoonBase7 Facts, missions, phases, news, links. Also dedicated to the space in general and robotics. |
| NSSDC_Photo_Gallery__Moon Select images from various space probes and telescopes. |
| The_Origin_of_the_Moon Scientific research report providing overview of current theories. |
| SMART-1__ESA\'s_Mission_to_the_Moon Official mission site includes articles, images, FLASH presentation, PDF brochures, etc. |
| Summer_Moon_Illusion An explanation of the illusion that the Moon, low on the horizon, is actually bigger then when seen higher in the sky. |
| What\'s_a_Blue_Moon? From Sky and Telescope magazine. Explains what it is and when the phenomenon happens. |
| Woman_in_the_Moon Several features of lunar landscape combined can be seen as a profile of a woman. |
| April_3_1974 Details on the Super Outbreak of Tornadoes that spawned 148 tornadoes, including thirty F4's and six F5's, in one day. |
| Bangladesh_and_East_India_Tornado_Prediction_Page A climatology of tornadoes for east India and Bangladesh, and the daily prediction of tornadoes are provided. Surface and upper air charts for historical tornado cases for Bangladesh and India are pr |
| The_Disaster_Center_Tornado_and_Severe_Weather Tornadoes, weather watchers, fact sheet statistics for every state, and links to the Disaster Center states pages. |
| FEMA_-_Fact_Sheet_-_Tornadoes Tornado safety tips from the Federal Emergency Management Agency. |
| How_Stuff_Works__Tornado Illustrated basics about tornadoes and how they are rated. |
| Illinois_Tornadoes Tornado information and links with an emphasis on Illinois. |
| May_3rd_1999_Central_OK_Tornadoes A comprehensive collection of links of the best of May 3rd sites. Both on the meteorological and human side. |
| Nature\'s_Most_Violent_Storms Information about tornadoes from the National Weather Service. |
| The_Online_Tornado_FAQ Roger Edwards of the Storm Prediction Center presents basic Frequently Asked Questions and the answers about tornadoes. |
| Online_Tornado_Museum Electronic museum is an educational look at the tornado. Most of the exhibits are photographs with explanatory text. |
| Sargodha,_Pakistan_Area_Tornado Extreme weather phenomena-tornado was reported in Sargodha region-Pakistan. The synoptic situation and subsequent damages are documented in this report. |
| Site_Assessment_of_Tornado_Threat Informational site for Vortek's Site Assessment of Tornado Threat (SATT 3.0) software. Provides the user with a means of quickly and accurately displaying and analyzing tornado data for any portion o |
| Storm_Chase_News_and_Archives A chronologically organized list of links to reports on and photos of individual tornado and other severe weather events. |
| Tahoe_Twisters Rare photographic collection of waterspouts and home page for GARYK and his unique scenic photography. |
| Tornado_Alley Twisters, tornadoes and Storm photos with educational information. |
| The_Tornado_and_Storm_Research_Organisation Independent and privately supported research body in the United Kingdom focusing on tornadoes and severe local storms. |
| Tornado_General_Information General Information on tornadoes, which includes safety tips and terminology page. |
| Tornado_Links This site has links to news and information about tornados. |
| Tornado_Project_Online! A company that researches, compiles and makes tornado information available to tornado and severe weather enthusiasts, the public, the meteorological community and emergency management officials in th |
| Tornadoes_and_Tornado_Research A comprehensive website on tornadoes with information on how tornadoes form, and what to do when a tornado strikes. Also featured pictures of tornadic damage, information on current tornado research, |
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EL NIÑO AND LA NIÑA
EL NIÑO AND LA NIÑA
EL NIÑO Y LA NIÑA EN ESPAÑOL
El Niño and La Niña: Tracing the Dance of Ocean and AtmosphereOf Weather and ClimateStarting with the AtmosphereA Meteorologist Looks at the SeaOceanography's PerspectiveWake Up CallNeed for More Comprehensive DataThe Power of an Interdisciplinary ApproachTimelineAdditional LinksCredits
El Niño and La Niña:
Tracing the Dance of Ocean and Atmosphere
By now most people have heard of El Niño, if only to know the name refers to some kinds of abnormal weather. The definition of "abnormal" varies widely with geography, though. For people who live in Indonesia, Australia, or southeastern Africa, El Niño can mean severe droughts and deadly forest fires. Ecuadorians, Peruvians, or Californians, on the other hand, associate it with lashing rainstorms that can trigger devastating floods and mudslides. Severe El Niño events have resulted in a few thousand deaths worldwide, left thousands of people homeless, and caused billions of dollars in damage. Yet residents on the northeastern seaboard of the United States can credit El Niño with milder-than-normal winters (and lower heating bills) and relatively benign hurricane seasons.
Originally, the name El Niño (Spanish for "the Christ child") was coined in the late 1800s by fishermen along the coast of Peru to refer to a seasonal invasion of warm southward ocean current that displaced the north-flowing cold current in which they normally fished; typically this would happen around Christmas. Today, the term no longer refers to the local seasonal current shift but to part of a phenomenon known as El Niño-Southern Oscillation (ENSO), a continual but irregular cycle of shifts in ocean and atmospheric conditions that affect the globe. El Niño has come to refer to the more pronounced weather effects associated with anomalously warm sea surface temperatures interacting with the air above it in the eastern and central Pacific Ocean. Its counterpart--effects associated with colder-than-usual sea surface temperatures in the region--was labeled "La Niña" (or "little girl") as recently as 1985.
The shift from El Niño conditions to La Niña and back again takes about four years. Understanding this irregular oscillation and its consequences for global climate has become possible only in recent decades as scientists began to unravel the intricate relationship between ocean and atmosphere. Although meteorologists have long been forecasting daily weather based on atmospheric measurements taken around the world, they had relatively little information about conditions in many parts of the world's oceans until the advent of arrays of fixed unmanned midocean buoys in the Pacific Ocean and orbiting satellites.
But technological advances were not the only key. As the following article recounts, atmospheric and oceanographic researchers, after years of independent inquiry into the basic workings of air and sea, at last joined forces. An elegant synthesis of these two fields of research now enables climatologists and oceanographers to construct theoretical models to simulate and predict the broad climate changes associated with ENSO. For example, scientists can now warn vulnerable populations of an impending El Niño event several months in advance, providing precious time in which to take steps to mitigate its worst effects. Invaluable as this prediction of El Niño is, it is just the first step toward the much longer-term goal of providing the climatic counterpart to the daily weather prediction that we have come to take for granted.
Flooded area in Lakeport, California as a result of the 1998 El Nino event. (Federal Emergency Management Agency)
Bush fire in Australia as a result of the 1998 El Niño event. (Photo courtesy of Fred Hoogervirst/Panos Picture/London)
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