Globalwarming, Ice Core Samples, Dendrochronology and Peat Bogs
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Global warming, Ice Core samples, Dendrochronology and Peat Bogs.
Global warming is the rise of average temperature in the earth’s atmosphere since the late 19th century. Since the beginning of the early 20th century, the earths mean surface temperature had increased by around 0.8 degrees. Warming of the climate system had become more obvious and scientists are 90% sure that the main cause of the increase in temperature in due to the increasing concentrations of greenhouse gases due to human activities such as deforestation and burning of fossil fuels.
Glaciers are melting, sea levels are rising, forests are drying and wildlife is suffering, these are all results of the apparent rise in global temperatures and it has become more…show more content… There is a positive correlation as the year increases so does the temperature anomaly. Satellites are useful as they measure the radiances in wavelength bands, which are then mathematically inverted to form indirect readings of temperature.
Dendrochronology is a method using the annual nature of tree growth to determine changes in climate settings. Each year trees develops a new layer of wood under its bark. The thickness of each layer is dependent on various factors, especially climate. The conditions encouraging growth will result in a wider tree ring, whereas the unfavourable conditions would result in narrow rings. By measuring the width of each tree ring and plotting them as graphs, scientists are able to determine the climate changes throughout the years.
They do this by comparing the tree rings and dating them to the calendar year in which they were formed. By matching the patterns (crossdating) the ring growth of different trees, scientists are able to assign the rings to specific dates. Crossdating can even be achieved in spite of the human interference to the tree ring growths and other factors such as extreme weather conditions. Overall dendrochronology is a very accurate technique where determination of absolute dates to year is either theoretically or practically possible.
Limitations of dendrochronology may lead to invalid results. In parts of the world, specifically the tropics, species of trees will not have a