El-nino
There's trouble in the air. Specifically, in the west coast of the Americas, where the sea surface has been heated to abnormal extremes by an ominous, intermittent flood of hot water called El-Nino. The term. "El-Nino," which means "the child," was originally in reference to a warm current arriving annually during the Christmas season off the coast of Peru and Ecuador. The term was later restricted to the particularly strong periodic warmings that disrupt the local fish and bird populations, and extend westward across the equatorial Pacific Ocean to near the date line. What is an El-Nino? El-Nino is the warming of the Pacific waters that is brought about from time to time by naturally occurring oscillations in atmospheric pressure and ocean movements in th equatorial Pacific. The warmer ocean pumps more energy and moisture into the atmosphere and this in turn alters wind and rainfall patterns around the world. The atmospheric cirulation also changes when the sea-surface temperatures in the eastern tropical Pacific rise above normal. In normal, non-El Nino conditions, the trade winds blow towards the west across the tropical Pacific. These winds pile up warm water in the west Pacific, so that the sea surface is about 1/2 meter higher at Indonesia than at Ecuador. The sea surface temperature is about 8 degrees C higher in the west, with cool termperatures off South America, dut to an upwelling of cold water from deeper levels. This cold water is nutrient-rich, supporting high levels of primary productivity, diverse marine ecosystems, and major fisheries. Rainfall is found in rising air over the warmest water, and the east Pacific is relatively dry. Warming of the Pacific waters is not the only thing El-Nino is to be blames for. The current El-Nino warming has been so strong, is has added noticeable zip to atmospheric winds and slowed Earth's spin, suggest scientists who track the planet's rotation. El-Nino exert these profound effects by speeding up the eastward movement of the atmosphere, relative to the solid body of te planet. The change shows up in the analyses of the atmosphere's angular momentum-a property comparable to the momentum of a spinning tire. "From mid-March through late November 1997, the angular momentum remaind significantly above average" (Monastersky 45-46). During non-El Nino years, winds in the tropics blow from east to west, whereas winds over the rest of the globe travel from west to east. Combined, they give the atmosphere a net eastward momentum. The atmosphere routinely trades some of this momentum back and forth with the solid Earth as winds drag across the surface of the planet and push against the mountain ranges. In the Northern Hemisphere's winter, the atmosphere speeds up and Earth slows. In summer, the reverse happens. El-Nino also boosts the atmosphere's angular momentum by slowing down the tropical easterlies and speeding the westerlies outside the tropics. As the atmosphere speeds up during El Nino, earth itself slows down to conserve the combined angular momentum. John M. Gipson of NASA's Goddard Space Flight Center in Greenbelt, Md., has tracked the planet's spin by monitoring changes in the length of the day. Over a typical year, the day shortens and lengthens by roughly 1 millisecond, mostly because of shifts in atmospheric angular momentum. During the current El Nino, the day has grown longer by four-tenths of a millisecond. Last year, Earth squeaked past the previous record high for globally averaged temperatures, continuing a balmy trend that has made this decade the hottest in more than a century of temperature data. "All of us are pretty happy with the agreement of the different methods," says Thomas R. Karl of the National Climate Data Center (NCDC) in Asheville, NC. "There are differences [among the teams' findings], but they are small" (Karl 38). Earth's land and ocean surface last year was 0.42 degrees C warmer than the long-term average of 16.5 degrees C for the reference period 1961 through 1990, says Karl. The NCDC team analysed data from more than 5,000 land stations and from water temperature reading collected by satellite sensors, buoys, and ships. 1997 came in almost a tenth of a degree warmer than the previous record years, 1990 and 1995, which were virtually identical in the NCDC data. Researchers play down the differences among these three years becuase the uncertainties in the figures exceed the gaps between them. The important message is that 9 of the top 10 warmest years on record have occurred since 1987. Such evidence adds weight to arguments that humans are altering climate in noticable ways. It is likely that greenhouse emissions are playing a role in the sustained upward trend in temperatures. El Nino helped push Earths temperature into a new territory last year by producing a vast pool of warm water in the equatorial Pacific Ocean. Even without El Nino, however, global temperatures would have remained high. During the first few months of 1997-before El Nino blossomed-the land surface was already quite warm. In contrast to the global pattern, eastern North America stayed ...
....and what are we g is caused by pollution containing sulfur dioxide, nitrogen oxide, and ozone ( SO', NOx, and O' ) is released into the air. These chemicals are absorbed into clouds and results in Acid Presipitation ( , Acid Snow, Acid Hail, Acid Sleet ). When the chemicals aren't absorbed into clouds, they can drift for miles and fall...
For about 50 years, antibiotics have been the answer to many bacterial infections. Antibiotics are chemical substances that are secreted by living things. Doctors prescribed these medicines to cure many diseases. During World War II, it treated one of the biggest killers during wartime - infected wounds. It was the beginning of the antibiot...
Acid rain: scourge from the skies Acid Rain: Scourge from the Skies 'North Americans have been smelting ore and burning fossil fuels for generations. In the past, the gases went up ordinary chimneys or small smoke stacks, to descend upon near by areas and pollute them,' states author, Robert Collins. Almost everyone knows what acid rain is...
1. a) Bulk movement is the overall movement of a fluid. The molecules all move in the same direction. Diffusion however is the random movement of molecules which usually results in a fairly even distribution. In other words the movement is not guaranteed to move in one direction but the probability that it will move in the l...
Handling Stress This essay is about handling the stress of University studies. We will be looking into many ideas and different people's views on how to handle stress. I will also be giving my own opinions on how I think stress can be controlled or relieved. The first thing we must do is ask ourselves one very important question, 'what is...
When dinosaur bones were first found they thought that they belonged to giant lizards. The word "dinosaur" came from the Greek words deinos, meaning 'marvelous' or 'terrible,' and sauros, meaning 'lizard.' The larger dinosaurs must have seemed to be terrible to the smaller animals. Some of the first dinosaurs were only about as big as a small...
The animal that I picked to reasherched on is a house cat. Classify: The cat would best fit in the Animalia kingdom. phylum: Chordata(vertebrate) Class: Mammals Order: Pulicidae Family: Siphonaptera Genus: Felis Species: domesticus (a) It depends on others for food. (b)Cells are flexible. The way a cat woul...
England went through dramatic changes in the 19th century. English culture, socio-economic structure and politics where largely influenced by the principles of science. Many social expressions occurred due to these changes. Transformations which categorized this time period could be observed in social institutions; for instan...
Cannibis Sativa Throughout history marijuana has been used to serve various purposes in many different cultures. The purposes have changed over time to fit in with the current lifestyles. This pattern is also true in American history. The use of marijuana has adapted to the social climate of the time. Marijuana, whose scientific name is cannibi...
During 1997, an event doctors had been fearing finally occurred. In three geographically separate patients, an often deadly bacterium, Staphylococcus aureus, responded poorly to a once reliable antidote--the antibiotic vancomycin. Fortunately, in those patients, the bacteria remained susceptible to other drugs and was eradicated. But the appear...
The Year 2000 Bug As the millennium approaches we come closer and closer to what some say could mean the end of civilization as we know it. What is this great event that would have such an impact on the world that it could end civilization? The problem is a simple computer bug refereed to as the Y2K bug but its ramifications could be im...
Science , ancient art practiced especially in the Middle Ages, devoted chiefly to discovering a substance that would transmute the more common metals into gold or silver and to finding a means of indefinitely prolonging human life. Although its purposes and techniques were dubious and often illusory, alchemy was in many ways the predecessor of...
It all started back in 1953 with two men by the names of James D. Watson and Francis Crick when they discovered the double-helical structure of DNA. Little did they know they were opening the door to the creation of a perfect world. In 1986, the Human Genome Project, led up by the National Institution of Health(NIH), took a giant le...
Down Syndrome Down Syndrome is a chromosomal disorder. It occurs in about 1 of every 800 births. People with Down syndrome may have mild to severe learning disabilities. Physical symptoms include a small skull, extra folds of skin under the eyes, and a protruding tongue. People with Down syndrome are subject to a variety of medical problems...