Precipitation means falling of frozen or liquid water from the clouds. It is irregular and scientifically, its characteristic highly depends on temperature. Temperature determines the amount of moisture through alteration on the supply by wind and surface evaporations. This moisture latter condenses to fall as rain or snow.
There are various aspects of precipitation that today exhibits large natural variability such as El Nino.
The changes in the atmospheric distribution pattern such as Atlantic oscillation have significant influence over the intensity, mode, frequency and type of precipitation. (Pinet, 2008) Current observations indicate a widespread of heavy precipitation and more falling in form of water as opposed to snow. According to Pinet (2008), this phenomenon is only associable to an increase in the atmospheric vapour rising from the oceans at lower latitudes due to global warming. Various regions across the globe have suffered from floods or drought. For this reason would it be right to speculate that, “The amount, frequency, intensity and type of precipitation depends on the climatic changes”? This paper forms the basis for casual analysis in support of this precipitation reliance. 194 nations met to discuss the environmental agreements and establish an accord at the Copenhagen Climate Change Conference in December 7 to18, 2009.
Each country agreed to set emission targets for 2020 and according to Athanasiou of ‘The Cornell Daily Sun’ (February 10, 2010), the United States submitted its goals to the United Nations on January 28, President Barack Obama’s commitment indicated a cut of green house emissions by four percent. These human induced emissions affect the evaporation procedures and consequently precipitation. The rising of air occurs due to convection from local heating of the earth’s surface and thus warm air rides over cooler air. Human induces incidents such as greenhouse emissions increases evaporation, as long as there is adequate moisture. The surface moisture equally becomes a conditioner and heat for evaporation moistens the air instead of warming it, thus higher temperatures and in some cases increased precipitation.
The current high rate of drying on the earth’s surface occurs due to warming. This means an increase in the potential of severe drought occurrence as observed in majority of the places worldwide.
According to Alzman (2007), from established scientific laws, the clausius-clapeyron relation indicates that the water holding capacity of the atmosphere increases by approximately seven percent for every one percent increase in temperature. Trends of relative humidity remain the same throughout the troposphere, thus the fact that there exists increased atmospheric water vapour and consequently increased precipitations. Today majority of the geographical settings experience heavy rainfall intensity or snowing because it emerges from the weather systems feeding the water vapour in the atmosphere.
From this basic climatic theory, there is scientific confirmation that more intense precipitations are because of water climates due to increased moisture. Stronger events such as El Nino are prone during the overall precipitation increase. Warm climatic conditions are therefore a risk for both floods and droughts thus the reason why some sections of the globe suffer from one calamity while the other suffer from the inverse. Other scenarios are seasons of floods and consequently unbearable heat as experienced in 2002-2003 in Europe.
El Nino cycle affects the subsequent distribution and timing of the El Nino or drought phenomenon particularly at the tropics. There are severe decreases of evaporation rates on the earth’s surface, thus the reduced moisture content in regions masked with aerosol pollutions. (Pinet, 2008) This is the key determinant of the frequencies and durations of precipitations, since it takes time to replace the aerosol masks for increased amount of vapours. The atmospheric circulation rates and patterns are a determinant of precipitation characteristic as well. Circulation patters involves the El Nino and oscillations of wind strengths over north Atlantic especially during winter among other variable patterns.
Current trends of drought have become widespread throughout various tropical and sub tropical regions in Africa because of the spotty or alternating nature of rain patterns, which causes the complexities involved. Weathermen have long-term records of varying precipitation patterns with prolonged severe droughts interfered with by heavy El Nino rains or vice versa. For instance, the 2005 wet winter in southern United States was a cover of a hard-hitting six years of drought with recordings of below the normal snowpack. (Lyon and Barnston, 2005) The episodes of El Nino differ in terms of strength, onset time, demise, maximal temperature and maturity.
For instance, the temperature records for the 1997-98 episodes were higher in comparison to those of 1994-95. The existence of the El Nino phenomenon depends on the interaction or coupling involving the atmosphere and the ocean. Today, the definition of El Nino phenomenon remains elusive as it were in the past. Considering the recent events, experts have questions regarding the classification of prolonged heavy rains as El Nino, but the answers depend on the variant definition of the El Nino Phenomenon.
Geographers and other weather experts are able to predict occurrence based upon the pacific conditions. Countries such as Brazil, Australia, Ethiopia, Peru and India have successfully been able to predict the El Nino phenomenon in favour of its agricultural plans. All these countries are strategically located partially within tropics thus the ease of forecast. They get the occurrence and impartial share of climatic impacts at the sections of the world where predictions regarding climate are at the greatest accuracy possible.
The other countries outside the tropics such as the United States suffer from predictions that are more accurate and therefore require enhancing better strategic planning in agricultural sectors, water resource management, grains and fuel/oil reserves. The scientists in support of most governments are working for the design of a global system capable of scrutinizing tropical oceans and climate variations in the aim of predicting El Nino occurrences besides performing a routine check of already existing variables. This involves a close correlation with the weather forecasters’ reports. Ability to anticipate and correctly predict climatic changes from one year to another enhances the economy due to well-managed agriculture and resource supplies. Proper understanding of the climatic conditions for accurate predictions enhances good management decisions thus better adoption of humankind perception and survival in line with the climatic rhythms.
According to the National Oceanic and Atmospheric Administration (NOAA), have the sole responsibilities of providing the federal government with routine climate forecasts and accurate predictions. Various descriptions of events pertaining climatic changes face further processing by the scientists into numerous projects such as the computer aided designs to process raw data concerning nature. (NOAA, 2010) Arrays of numerals representing the atmospheric records fed into the computers to generate records of information for the predictions.
The main impacts of the climatic conditions are the winds and clouds.
The wind referred to as easterlies brows winds along the equator causing cool water to come near the surface and at full strength, the water chills the air above it, thus causing it to become too dense to rise and eventually condenses to form clouds and subsequently a precipitate. (Pinet, 2008) This aspect causes the ocean to be free of cloud covers and therefore confinement of the rain along the belt at the equatorial to the western pacific. During the early stages of the El Nino, the easterlies weaken, causing the oceans to warm and consequently the air above it.
This is therefore the initial stage in the formation of the deep clouds and heavy rains along the equator. Temperature changes at the ocean are therefore the source of the heavy rains. These ocean zones are major rain sections but it shifts eastwards over the western pacific. The dialogue between the sea and wind is strong and the minor perturbation eventually amplifies thus causing a full-fledged El Nino. It is difficult to predict the changes at the atmospheric system near the oceans as the initial catalysts for the transitional El Nino Phenomenon, but it is easy to have predictions at such areas.
This is the reason why some countries are in a better position of having accurate predictions than others.
In categorization of El Nino as either strong or weak, the choice regarding definition fails to work because of the existence of multiple aspects of climate responses in a particular country or region. To most people especially in the impacted regions, the phenomenon depends upon the associated conditions and time of occurrence, rather than physical principal conditions of discoveries. There are many differences of understanding regarding the causes and thus lack of a specific definition of El Nino. Specific definition of the phenomenon is a complex challenge that this analysis proposes for further findings. The existing definitions are equality subject to further revisions with respect to the continual scientific research findings.
R. (2007). Clapeyron and Clausius-Clapeyron Equations: Chemical Thermodynamics. University of Arizona. Archived from the original Athanasiou, K. (2010). Copenhagen: Sustainable of Superficial? The Cornell Daily Sun.
Retrieved February 10, 2010 from http://www.cornellsun.com Lyon, B. & Barnston, A.
G. 2005. International Research Institute for Climate Prediction (IRI), Palisades, New York, USA Retrieved February 10, 2010 from http://www.iri.columbia.edu National Oceanic and Atmospheric Administration (NOAA). (2010) Climate Forecasting. Retrieved February 10, 2010 fromhttp://www.
noaa.gov/ Pinet, P.R. (2008).
Invitation to Oceanography. (Fifth Ed). Jones & Bartlett Publishers