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=__ HOW NATURAL PHENOMENAS AFFECT CLIMATE : __=

__**Introduction to Climate Change**__ Climate is the long-term statistical expression of short-term weather. Climate can be defined as "expected weather". When changes in the expected weather occur, we call these climate changes. They can be defined by the differences between average weather conditions at two separate times. Climate may change in different ways, over different time scales and at different geographical scales. In recent times, scientists have become interested in global warming, due to mankind's impact on the climate system, through the enhancement of the natural greenhouse effect. The overall state of the global climate is determined by the amount of energy stored by the climate system, and in particular the balance between energy the Earth receives from the Sun and the energy which the Earth releases back to space, called the global energy balance. How this energy balance is regulated depends upon the flows of energy within the global climate system. Major causes of climate change involve any process that can alter the global energy balance, and the energy flows within the climate system. Causes of climate change include changes in the Earth's orbit around the Sun, changes in the amount of energy coming from the Sun, changes in ocean circulation or changes in the composition of the atmosphere. Large volcanic eruptions can affect the global climate over only a few years. By contrast, the movement of continents around the world over hundreds of millions of years can also affect global climate. Throughout the Earth’s history climate has fluctuated between periods of relative warmth and relative cold. Palaeoclimatology is the study of climate and climate change prior to the period of direct measurements. Direct records of temperature and other climatic elements span only a tiny fraction of the Earth's climatic history, and so provide an inadequate perspective on climatic change and the evolution of the climate today and in the future. A longer perspective on climate variability can be obtained by the study of natural phenomena which are climate-dependent. Such phenomena provide a record of past climates, and are revealed through the study of, amongst other techniques, tree rings, ice cores and sea floor sediments. //** Volcanoes **// Atmospheric pollution from major volcanic eruptions can influence the global climate over one to two years. Explosive volcanic eruptions can inject large quantities of dust and sulphur dioxide, in gaseous form, to an altitude of over 10 miles into the atmosphere (the stratosphere), where the sulphur dioxide is rapidly converted into secondary sulphuric acid aerosols. Whereas volcanic pollution from smaller eruptions, ejected only a few miles into the atmosphere, is removed within days by rain, the volcanic dust and aerosols in the stratosphere may remain for up to two years, gradually spreading over much of the globe by winds. Volcanic pollution results in a 5 to 10% reduction in direct sunlight, largely through scattering as a result of the highly reflective sulphuric acid aerosols. Large eruptions can bring about a short but noticeable global cooling of up to 0.3°C. Immense lava flows, now known as the Deccan Traps, released huge quantities of gases, including sulphur dioxide and carbon dioxide. It is possible the longer term changes in the amount of volcanic activity on the Earth may explain incidences of longer term climate change during Earth History.

====El Niño, which affects wind and rainfall patterns, has been blamed for droughts and floods in countries around the Pacific Rim. El Nino refers to the irregular warming of surface water in the Pacific. The warmer water pumps energy and moisture into the atmosphere, altering global wind and rainfall patterns. The phenomenon has caused tornadoes in Florida, smog in Indonesia, and forest fires in Brazil.====
 * __ El Niño __**


 * __ Devastation caused by an El-Nino which generated a tornado in Florida __**


 * __ Forest fire caused by El-Nino __**


 * La Niña [] **




 * // T //****// HIS SHOWS THE EL NINO EFFECT WE HAD LAST WINTER. //**


 * Biosphere Process **

There are many different ways that the plants, animals and other life on our planet, affect the biosphere therefore our climate. Some produce greenhouse gases that trap heat and aid global warming.
====· Plants: The greenhouse gas carbon dioxide is taken out of the atmosphere by plants as they make their food by photosynthesis. During the night, plants release some carbon dioxide into the atmosphere. They take much more carbon dioxide out of the atmosphere than they put in.==== ====· Farm animals: The greenhouse gas methane is made as farm animals, such as cattle and sheep, digest their food. · Wetlands and rice patties: Microbes in natural wetlands and rice paddies produce methane gas.==== ====· Factories and power plants: carbon dioxide gas is releasing into the atmosphere when fossil fuels are burned to make the power needed for most factories and power plants. · Cars and trucks: Carbon dioxide gas is released when fossil fuels are burned to power cars and trucks.====

· Fertilizers: The greenhouse gas nitrous oxide is produced when human-produced fertilizers breakdown in the soil.
====· Wildfires: Carbon dioxide is released into the atmosphere as wildfires burn. However, if a forest of similar size grows again, about the same amount of carbon that was added to the atmosphere during the fire will be removed.====

**//BIBLIOGRAPHY//**

 * ======**BC Science 10 Text Book**======
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 * ======**[|http://en.wikipedia.org/wiki/Climate_chagen]**======
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