Environmental Science

Questions: 1. What is the name of the atmospheric component of ENSO and what does the expression describe?2. Describe the Walker Circulation and how this changes between El Nino and La Nina events.3. What is the name of the oceanic component of ENSO and where does the name come from? 4. How does the sea level in the eastern Pacific change during an El Nio event - is it higher or lower than usual? What is the magnitude of this sea level change? - is it in the order of centimetres, metres, or decametres?5. Why are El Nio events detrimental to commercial fishing in the eastern Pacific?6. In which parts of Australia can agricultural production be strongly affected by ENSO?|7. How often do ENSO-driven droughts occur (on average)?8. What does a highly negative and persistent (winter and spring) SOI indicate in terms of rainfall in Queensland?9. What year could we be describing in the two scenarios on the first page? 10. Scenarios 1 and 2 on p. 1 of the practical refer to eastern Australia and coastal Peru. Impacts of ENSO may also be felt elsewhere in the world. Describe two other areas in the world where ENSO impacts may be felt, and what are they? Answers: 1. Southern Oscillation is the name given to the atmospheric component of ENSO phenomenon(Bureau of Meteorology, 2015). The huge shifts of the tropical atmosphere mass have been between west Pacific and India and Ocean and East Pacific from east to west. This has been associated with this atmospheric component. This component influences the atmosphere of the ocean by anomalies because of the pressure exerted by the winds on the surface. In return, the ocean influences its atmosphere by anomalies within the surface temperatures of the ocean. This is attributable to the upward fluxes caused by the ocean latent heat. 2. The description of Walker circulation between El-Nino and La-Nina events can be found in the neutral phase of the ENSO. At this phase where none of the two events occur. Instead, the trade winds blow from east to west all through the tropical Pacific Ocean surface. This event brings a warm and moist air on the surface of the ocean waters in the direction of the western Pacific while at the same the central Pacific Ocean remains cool. In the end, thermocline becomes deeper in the west when compared to the east. This phenomenon of the air rising from the west and blowing and falling in the east is the one described as Walker Circulation(Liberto, 2014). 3. El-Nino is the name given to the oceanic component of ENSO(Tisdale, 2014). Over the decades this name has been associated with the annual weak and warm currents that rise along the Ecuador and Peru coasts especially near or around the Christmas period. As a result, these currents replaces the colds waters in the Peru Current. Therefore, the origin of the El-Nino is closely associated with the Spanish word meaning the boy Christ child Meaning this ENSO component occurs on an annual basis during Christmas time(National Ocean Service, 2016). 4. It is usually known that the El-Nino events in the Pacific Ocean greatly impacts both the weather patterns and the temperatures around the world. However, the impacts of this event are widespread as they still affect the Pacific Ocean sea levels. Therefore, it is quite clear the variations in the sea levels cannot be ignored. It is due to this fact; this paper aims to explore the effects of the El-Nino on the sea levels of the Eastern Pacific. During this period the sea levels in the Eastern Pacific are usually higher than usual. This is because of the warm water which causes expansion and thus resulting in the rise of the sea levels by several centimeters. 5. From the analysis of the El-Nino impacts is has come out clearly that it results to warming of the ocean waters. As a result, the expansion of the ocean waters sets in, and the sea level starts to rise. High temperatures will, in turn, interfere and affect the aquatic habitat of the fishes. To avoid this unfavorable environment, a lot of fish will migrate towards the cool regions causing to the reduction of the fish in regions experience the effects of El-Nino events. As an entrepreneur who has ventured in the commercial fishing activity, he or she will incur a loss due to the reduced catch. Alternatively, the entrepreneur may end up losing some of his or her customers to the competitors due to the shortage of fish products in the market. 6. Australia has been termed as a fairly dry continent. This is because of the continents rainfall variability which is not reliable. This phenomenon has been attributed to the components of ENSO that is El-Nino and Southern Oscillation. Since it, ENSO occurrence some parts of Australia has been facing droughts of the decades. This is because of the cold oceans currents which create high pressure on the land hence increasing the probability of dryness. For example, the regions of Victoria, Western Australia, New South Wales, South Australia and Queensland have been largely affected by this phenomenon. 7. The findings indicate that Australia has been a victim of droughts associated with ENSO components. Additionally, it has been found that many of the huge droughts that have occurred in Australia have direct with the ENSO effects. For example, 1914- 1915, 1983-1983 and 1991 1995 droughts were as the result of the ENSO. Also, it has been concluded that on average the drought in Australia occurs within a range of three to seven years. Therefore, at the range of five and half years can be termed to be average at which the drought do occur in Australia. 8. From the Study of the SOI negative and persistence continuance of the low rainfall during winter and spring phases has always been followed by the heavy rains. Similarly, the low rainfalls in Queensland during winter and spring periods it is an indication that the region will experience high rainfall with the shortest span of time. However, the rains do not continue for long as the findings have found that the heavy rains have broken the begging of the huge drought. 9. Considering the two scenarios, the year 1995 seems to describe them. This is because of the country in scenario one the region was experiencing drought and high sea levels. However, it has always been the case a period of heavy rainfall was experienced. Alternatively, in scenario two region in eastern Australia seems to suffer from drought after the phase of El-Nino. 10. Eastern Australia and the coastal parts of Peru are not only the areas experiencing the effects of ENSO alone. There are other regions of the globe which have faced the similar ENSO consequences. For example, some parts of the United States and the Northern Europe seems to suffer from the effects of ENSO. The findings how that in the US Pacific Decadal Oscillation cause the variability in the sea temperatures and return affect the weather patterns. Alternatively, ENOS has been proved to have strong connections with the droughts that occur in several regions of America, Central America, and Western Pacific Islands, in some parts of Africa, Brazil, Philippines, India and Indonesia(Woods Hole Oceanographic, 2015). References Bureau of Mateorology. (2015, 2 April). Southern Oscillation Index. Retrieved from https://www.bom.gov.au: https://www.bom.gov.au/climate/glossary/soi.shtml Liberto, T. D. (2014, August 1). The Walker Circulation: ENSO's atmospheric buddy. Retrieved from https://www.climate.gov: https://www.climate.gov/news-features/blogs/enso/walker-circulation-ensos-atmospheric-buddy National Ocean Service. (2016, June 28). What are El Nio and La Nia? Retrieved from https://oceanservice.noaa.gov: https://oceanservice.noaa.gov/facts/ninonina.html Tisdale, B. (2014, April 30). The 2014/15 El Nio Part 6 What's All The Hubbub About?... Retrieved from https://wattsupwiththat.com/: https://wattsupwiththat.com/2014/04/30/the-201415-el-nino-part-6-whats-all-the-hubbub-about/ Woods Hole Oceanographic. (2015, September 6). El Nio Other Oscillations. Retrieved from https://www.whoi.edu: https://www.whoi.edu/main/topic/el-nino-other-oscillations