Global Warming, Ice Core Samples, Dendrochronology and Peat Bogs Essay Sample

Global heating is the rise of mean temperature in the earth’s atmosphere since the late nineteenth century. Since the beginning of the early twentieth century. the earths average surface temperature had increased by around 0. 8 grades. Warming of the clime system had become more obvious and scientists are 90 % sure that the chief cause of the addition in temperature in due to the increasing concentrations of nursery gases due to human activities such as deforestation and combustion of fossil fuels. Glaciers are runing. sea degrees are lifting. woods are drying and wildlife is enduring. these are all consequences of the evident rise in planetary temperatures and it has become more obvious that humans over centuries are let go ofing harmful heat-trapping gases into the atmosphere known as nursery gases.

The nursery consequence causes the addition in planetary temperature as the gases which are released into the atmosphere allow visible radiation to be entered. but prevents heat from get awaying. The Sun foremost releases short-wave radiation which skinks into the earth’s surface. doing it to warm the ambiance. A long moving ridge infrared radiation which is emitted by the earth’s surface is absorbed. and so re-emitted back into infinite. The clime alterations occur due to the addition of nursery gases. The nursery gases so pin down some of the heat and the remainder escapes back into infinite. Basically. the more nursery gases released into the ambiance. the more heat is trapped. ensuing in an addition of planetary clime.

The above graph shows the rise in planetary temperatures since 1860 to 2000. The addition in planetary temperature can be entering utilizing methods such as: Ice nucleus samples ; temperature recordings ; dendrochronology and peat bogs.

Ice nucleus samples
Within Ice sheets. holds records of 100s of 1000s of past climes trapped in antediluvian snow. Scientists can obtain the clime history by boring nucleuss in ice up to 3. 500 meters deep. Throughout every twelvemonth. bed of snow cover the ice sheets in Antarctica and Greenland. Within these beds of snow. contains a different chemical science and texture as the summer snow is different from the winter snow. Each of these beds provides scientists with information about the clime each twelvemonth. An ice nucleus provides a perpendicular timeline of old climes which are stored in ice sheets and mountain glaciers. In able to see the beds. scientist excavation into two cavities which are separated by a wall of thin snow. One of the cavities is covered and the other exposed to sunlight. By standing in the covered cavity. scientists are able to analyze the annual beds of snow wall as the sunshine filters through the other side.

The ice nucleuss can supply a annual record of temperature. atmospheric composing. precipitation. air current forms and volcanic activity. Using Marine dodos and the ratio of O isotopes in the snow can uncover the temperature. When snow is formed. it becomes crystallized around the bantam atoms in the ambiance. the sum of at bay atoms. such as dust. volcanic ash. fume or pollen can uncover to scientists the clime and environmental conditions of when the snow formed. As the snow is being settled on the ice. air fills into infinite between ice crystals and a bantam sample of ambiance is trapped. These little bubbles can state scientists what gases were in the ambiance and the clime at that clip. Ice nucleuss can besides be used to correlate the concentration of CO2 in the ambiance with the alteration in clime. as shown in the graph. Advantages of Ice nucleus dating is that the procedure can be completed rapidly and consequences are easy obtained. Disadvantages would be that is the preset age markers are wrong. so the age that is assigned to the ice nucleus would besides be wrong.

Temperature records
Through usage of orbiters. temperature of the troposphere can be measured. This method has been effectual since December 1978.

The Graph shows how the orbiters can be used to mensurate the temperature anomalousness. There is a positive correlativity as the twelvemonth increases so does the temperature anomalousness. Satellites are utile as they measure the glows in wavelength sets. which are so mathematically inverted to organize indirect readings of temperature.

Dendrochronology
Dendrochronology is a method utilizing the one-year nature of tree growing to find alterations in clime scenes. Each twelvemonth trees develops a new bed of wood under its bark. The thickness of each bed is dependent on assorted factors. particularly climate. The conditions promoting growing will ensue in a wider tree ring. whereas the unfavorable conditions would ensue in narrow rings. By mensurating the breadth of each tree ring and plotting them as graphs. scientists are able to find the clime alterations throughout the old ages. They do this by comparing the tree rings and dating them to the calendar twelvemonth in which they were formed. By fiting the forms ( crossdating ) the pealing growing of different trees. scientists are able to delegate the rings to specific day of the months.

Crossdating can even be achieved in malice of the human intervention to the tree pealing growings and other factors such as utmost conditions conditions. Overall dendrochronology is a really accurate technique where finding of absolute day of the months to twelvemonth is either theoretically or practically possible. Restrictions of dendrochronology may take to invalid consequences. In parts of the universe. specifically the Torrid Zones. species of trees will non hold a distinguishable seasonal form ; therefore it would be hard to find the clime alteration over the old ages. Besides if the correct species are gettable. the beds of wood must be preserved good plenty so that the rings can be read. basically there should be a lower limit of 30 rings in one sample.

To extinguish single fluctuations in tree ring growing. dendrochronologists take the norm of the tree pealing breadths of assorted tree samples to construct up a ring history. This procedure is known as reproduction. If a tree rings history is non known it is called a natation chronology. This is where cross dating is used. Peat Bogs

Peat bogs are formed from flooded hallows and basins that provide ideal conditions for growing of reeds and sedges. When flora dies. it does non decompose off wholly due to H2O remains in the hallows that prevent O. Partially rotted workss so bit by bit construct up to organize peat. Most of the foods are tied up within the peats. significance that the lone minerals available for works growing are the 1s dissolved in rainfall. A study by Natural England found that farming patterns such as plowing the Earth. consequences in three quarters of peat bogs to go damaged. This consequences in three million metric tons of C dioxide which is stored in the dirt to be released every twelvemonth. It is estimated that globally. peat bogs shops twice every bit much carton as wood. and the UK contains about 15 per cent of the world’s peatlands.

Decision
A reappraisal by Peter Stott of the Met Office Hadley in Exeter. found that ‘fingerprints of human activity on many different facets of clime alteration. “The fingerprint of human influence has been detected in many different facets of ascertained clime alteration. We’ve seen it in temperature. and increases in atmospheric humidness. we’ve seen it in salt alterations. We’ve seen it in decreases in Arctic sea ice and altering rainfall forms. ” Dr Stott said. “What we see here are observations consistent with a warming universe. This wealth of grounds we have now shows there is an progressively distant possibility of clime alteration being dominated by natural factors instead than human factors. ” Overall. through the information obtained through ice nucleus samples. Tree rings. temperature scenes and harm to peat bogs proves that worlds are to fault for planetary heating. Scientists have proven that the warming consequence on the Earth is chiefly due to the 1000000s of C dioxide emitted into the ambiance due to human activity over the old ages.

Referees

1. hypertext transfer protocol: //en. wikipedia. org/wiki/Global_warming
2. hypertext transfer protocol: //environment. nationalgeographic. com/environment/global-warming/gw-overview/ 3. hypertext transfer protocol: //earthobservatory. National Aeronautics and Space Administration. gov/Features/Paleoclimatology_IceCores/ 4. hypertext transfer protocol: //en. wikipedia. org/wiki/Temperature_record

5. hypertext transfer protocol: //www. shef. Ac. uk/archaeology/research/dendrochronology 6. hypertext transfer protocol: //www. humanistic disciplines. Cornell. edu/dendro/ajatext. hypertext markup language
7. hypertext transfer protocol: //www. doeni. gov. uk/niea/nh008. pdf
8. hypertext transfer protocol: //www. telegraph. co. uk/earth/environment/climatechange/7465370/Damage-t