The state of the Earth We are Old

CAUSES OF GLOBAL WARMING The cause of Global Warming. Increasing global temperature is expected to lead to other changes such as rising sea levels, increased intensity of extreme weather phenomena, as well as changes in the number and pattern of precipitation. Consequences of global warming or that global warming is terpengaruhnya other crops, the loss of glaciers, and the extinction of various animal species. Global Warming or Global Warming is the process of increasing the average temperature of the atmosphere, oceans, and Earth's land. Global average temperature at Earth's surface has risen 0.74 ° C ± 0:18 (1:33 ± 0:32 ° F) during the last hundred years. Intergovernmental Panel on Climate Change (IPCC) concluded that, "most of the increase in global average temperatures since the mid-20th century is most likely caused by increased concentrations of greenhouse gases due to human activities" through the greenhouse effect. These basic conclusions have been advanced by at least 30 scientific and academic bodies, including the national science academies of all G8 countries. However, there are still some scientists who disagree with some of the IPCC conclusions are presented The cause of Global Warming / Global Warming * Greenhouse Effect * Feedback Effects * Variations in the Sun Greenhouse Effect All energy sources that exist on Earth comes from the Sun. Most of the energy in the form of short-wave radiation, including visible light. When this energy arrives Earth's surface, he turned from the light into heat that warms the Earth. Earth's surface, will absorb some heat and reflecting back the rest. Much of this heat is tangible long-wave infrared radiation into space. But some of the heat remains trapped in Earth's atmosphere due to accumulated amount of greenhouse gases such as water vapor, carbon dioxide, and methane which trap this radiation. These gases absorb and reflect radiation emitted wave and consequently the Earth's heat is stored in the Earth's surface. This situation occurs continuously, resulting in an annual average temperature of the earth continues to increase. Gases are working in a greenhouse gas. With the increasing concentration of these gases in the atmosphere, the more heat is trapped underneath. The greenhouse effect is needed by all living things on earth, because without it, the planet will be very cold. With an average temperature of 15 ° C (59 ° F), the earth actually has more hot 33 ° C (59 ° F) from the original temperature, if there is no greenhouse effect the Earth's temperature is only -18 ° C so that the ice would cover the entire Earth's surface. However, on the contrary, if these gases in the atmosphere has been excessive, will cause global warming. Feedback effects Elements of the cause of global warming are also influenced by various feedback processes that result. An example is the evaporation of water. In the case of warming due to increasing greenhouse gases such as CO2, warming will initially lead to more amount of water that evaporates into the atmosphere. Because water vapor is itself a greenhouse gas, warming will continue and increase the amount of water vapor in the air until it reaches an equilibrium concentration of water vapor. The resulting greenhouse effect is greater than the effect of CO2 alone. (Although this feedback increases the absolute water content in the air, relative humidity of air is almost constant or even decreases slightly because the air becomes warmer). [3] This feedback effect only slowly as CO2 has a long age in the atmosphere. Feedback effects due to the influence of clouds is the object of current research. When viewed from below, clouds will reflect infrared radiation back to the surface, thereby increasing the heating effect. In contrast when viewed from above, clouds will reflect sunlight and infrared radiation to space, thereby increasing the cooling effect. Whether the net effect produce heating or cooling depending on some specific details such as the type and height of these clouds. These details are difficult to be represented in climate models, partly because the clouds are very small compared to the distance between the boundaries of computational climate models (about 125 to 500 km to the model used in the Fourth Report of the IPCC view). Nevertheless, cloud feedback ranks of two when compared with the water vapor feedback and is considered positive (adding heating) in all models used in the Fourth Report of the IPCC view. Another important feedback is the loss of the ability to reflect light (albedo) of ice. As global temperatures increase, ice near the poles melts at an ever increasing. Along with the melting of the ice, land or water below it will open. Both land and water has the ability to reflect light much less when compared to the ice, and consequently will absorb more solar radiation. This will increase the heating and causing even more ice melts, it becomes a continuous cycle. Positive feedback due to release of CO2 and CH4 from the softening of frozen ground (permafrost) are other mechanisms that contribute to warming. In addition, the melting ice will also cause release of CH4 are also positive feedback. The ability of oceans to absorb carbon will also be reduced if it warms up, this is caused by a decline in nutrient levels in the zone and limit the growth of diatoms Mesopelagic than phytoplankton is low carbon sinks. Variation of the Sun There is a hypothesis which states that the variation of the Sun, with a possibility reinforced by feedback from the clouds, can contribute to warming. Difference between the heating mechanism is due to the greenhouse effect is the increased activity of the Sun would heat the stratosphere reverse the greenhouse effect cools the stratosphere. Cooling the lower stratosphere has been observed since at least 1960, which will not occur when the solar activity to be a major contributor to recent warming. (Depletion of the ozone layer may also provide the cooling effect, but depletion occurred from late 1970's.) The phenomenon of solar variability combined with volcanic activity may have provided the warming effect from pre-industrial times to 1950, as well as a cooling effect since 1950 . There is some research that states that the contribution of the Sun may have been overlooked in global warming. Two researchers from Duke University estimated that the Sun may have contributed to 45-50% increase in average global temperature over the period 1900-2000, and about 25-35% between 1980 and 2000. Stott and colleagues suggests that climate models are used as guidelines now make exaggerated estimates of the effects of greenhouse gases compared with the influence of the sun, they also suggest that the cooling effects of volcanic dust and sulfate aerosols have also been underestimated. Nevertheless, they conclude that even by increasing the sensitivity of climate to influence sun though, most of the warming that has occurred in recent decades is caused by greenhouse gases. In 2006, a team of scientists from the United States, Germany and Switzerland stated that they did not find any increase in the level of "explanation" of the Sun in a thousand years. Solar cycle only a small increase of 0.07% in the "statement" for 30 years. This effect is too small to contribute to global warming. A study by Lockwood and Fröhlich found no relation between global warming and solar variability since 1985, both through the variation of solar output or variations in cosmic rays.