Global Climate change abstract Free Essay Example, 1000 words

Carbon Dioxide absorbs the energy of about 15 microns wavelength. The climate system responds to these forcing changes to achieve a new balance. Climate Past Amplified carbon levels in the atmosphere and the ocean marked the Paleocene-Eocene Thermal Maximum 55 million years ago. The temperature increased from 5 to 9 0C. This caused changes in the marine ecosystem, the evolution of mammalian body size and geological changes. The carbonate compensation depth rose as the ocean composition changed. The temperatures remained warm and decreased over 40,000 years. The Ice Age was marked by a reduction in the Earth’s temperature and lower sea levels. Sediments that accumulate on the ocean floor relate the atmosphere and the ocean. Eolian dust particles in the sediments is an indicator of humidity decrease and atmospheric circulation increase. Pleistocene cycling was described from the observation of sediment cores. Oxygen isotopic compositions of the shells depend on the ice content. Glacial ice has higher oxygen- 16 when compared to sea water. The climate of Pliocene epoch was characterized by cycles of warm and cold periods as shown by the oxygen isotope profiles. We will write a custom essay sample on Global Climate change abstract or any topic specifically for you Only $17.96 $11.86/pageorder now Milankovitch quantified and formalized the obliquity, eccentricity and the earth’s axis spin relative to orbital spin explaining the effect the earth’s revolution on insolation and hence climate. The theory, however, does not explain the glacial and interglacial cycles. Pleistocene epoch carbon dioxide concentration ranged between 170 and 300 ppm in a cycle of 100,000 years. The concentration of carbon dioxide is shown to be highest in present times. Ice Cores from Greenland Record of 108,000 years show climate oscillations with longer cold periods. Dansgaard-Oeschger was recognized in these ice cores. The Younger Dryas record shows abrupt shifts. The Holocene climate is the warmest and longest stable record. Past climates can also be inferred from lake sediments corals, tree rings, and caves. The climates in the 20th century are the warmest recorded. Past climates offer an analogy necessary in the study of present climate and expected climate in the future. Climate Models and the Future Climate models mathematically represent motions of water and air as a factor of energy from the sun and other contributing factors such as Coriolis forces. The atmosphere-ocean general circulation models coupled atmospheric and ocean circulation. A model is run by dividing the planet into a three-dimensional grid. The grid points represent a defined volume with specified properties.