MaureenGlobal climate change will effect every animal on this planet, including humans. Homes will be moved and cities will be changed. There will be no respect for political or social boundaries by the planet as it changes climates world wide. For this reason, climate change is a topic being discussed around the world from dinner tables to United Nations summits. Every man woman and child will be effected by the cycles of change that this planet endures. Governments worldwide are attempting to create solutions to ensure a minimal amount of damage to their citizens. Reporters around the world are bringing stories of regional changes into the living rooms of citizens in almost every country. This is a topic that is at the forefront of global discussion. For this reason it is crucial that a strong understanding of what climate change is and how it functions should not be reserved for researchers and scientists but taught to the masses and tackled by world leaders. It is essential that everyone understands the importance of gathering sound unbiased data on the subject so that world leaders are making informed decisions. With a subject like this it is impossible to have a narrow data set. Although modern climate data is important, it is essential that ancient environments are explored by means of lake coring, paleosol analysis and pollen analysis to fully understand the changes present in modern climates because this method will provide and accurate time line of the earth’s development, strong data support to understand modern climate change and to predict future climate change.
First, to be able to know anything about paleoenvironments a basic understanding of how the data about these environments are gathered is needed. An accurate method of doing this is by paleosol and pollen analysis. Paleosols, or ancient soils, and pollens can be gathered and analyzed by processes like lake coring. Because of the nature of water, pollen and soils are carried from supplying rivers and streams and deposited in the bottom of lakes. Today we can drill into the bottom of these ancient lakes and remove samples that contain these deposited soils and pollens. Looking at these depositions allows the researcher to determine specific species or plant life that was living in the area at the time of deposition. This gives us an idea of what the climate was like because there are certain species that are sensitive to climate change and are only able to live in specific types of environments.
The samples taken from lake coring for pollen and paleosols can also used as a method of relative dating to project a time line on these ancient environments. The layers that the pollens and soils form under the lake become laminated over time and are called varves. The varves accumulate over time piling up on top of the previous deposition. Eventually there will be a stratified description of the deposition history at the bottom of the lake. Basic geological laws dictate that, generally speaking, the oldest layer with be on the bottom and the youngest layer will be on the top. This enables us to know which phases of environment changes came first and which were more recent by correlating the pollens and soils to layers that they were found in.
Analysis of varve accumulation was used at Lake Nautajärvi in Finland to provide a chronology of temperature change int the region for the past several thousand years. The results of the research show, that “the organic component of varves show roughly comparable trends, indicating a direct influence of climate on the physical properties of the varves” (Ojala, 2008, 531). This means that using varves as a means to describe the climates of the past is a reliable and accurate because there is a direct correlation between what is seen within the varves and the climate. The end result of the research shows that “summer temperatures in Scandinavia did not follow the monotonic trend in the solar summer radiation but that they reached a peak considerably later…” (Ojala, 2008 536). The results of this project can provide important information about the way climates change over time. This shows that trends that may have been expected might not always manifest themselves and that each region will have a unique environmental history.
Another way to determine ancient environments is by studying the grain size of sediment deposition in various areas. Grain size and distribution of sediments can reveal a lot of information about the physical make up of the landscape. Large amounts of relatively large grain sizes imply that that area was near the source of the sediments. While very fine grained deposits show movement from the source by water or wind. Looking at grain size and distribution can determine if the area in question was under an ocean or a part of a desert. Knowing this has huge implications as to what the environment was doing in that area at the time. An article written by Piezhen et. al.(2001) uses grain size changes to demonstrate a global climate change around the world. The type of climate that is present at the time has a direct influence on what type of sediment will be deposited. Through their research, Piezhen et. al.(2001) have determined that there was a period of relatively stable climate that gave way to a period of more rapid and abrupt climate change. (Piezhen et, al., 2001) This is important today because it shows that the earth is capable of undergoing somewhat dramatic natural changes, and may continue to do so in the future.
The data gathered from methods such as these provide a very robust frame of reference to use for climate change discussion. The technology and knowledge exists that there can be a relatively large amount of confidence placed in the analysis of these geological and biological markers. Relative dating provided by varves allows for a testable hypothesis of chronology to be applied to whatever region is being studied. It is also important to note that these data sets can be cross referenced with other data sources. If there was a global climate change event, a record of it will be preserved in rocks around the world as paleosols and pollens. The geologic record will preserve clues of temperature changes and pole changes that will supplement the paleoenvironmental record determined through paleosols or grain sizes. These methods, combined with other forms of research, can provide a comprehensive assessment of the climates around the world.
It is also a credible data source because of the large time set it deals with. When dealing with a history billions of years long focusing on the most recent three hundred years would not provide an accurate sample size. This is why it is essential that data is collected from periods other than periods occupied by humans. One of the basic principals of any science is to acquire and adequate sample size that is representative of the population in question. Only looking one hundred years into the past provides a biased view of the data and can be problematic. Utilizing biased data is unexceptable in a world where national policies are beginning to depend more and more on the causes and effects of climate change. Even a study that looks only ninety thousand years into the past can provide a better view of how climate changes around the globe than trying to propose theories based on data gathered since the industrial revolution. Within those ninety thousand years Blunier and Brook were able to demonstrate a strong relationship between climate changes at high latitudes on either side of the globe. Their research shows that changes in climate are directly connected from pole to pole. They were able to do this because they had a large enough sample size to demonstrate trends on a millennial scale (Blunier and Brook). Looking far into the past shows trends in the world’s history that cannot be seen if the research is focused on too small of a sample size.
Once scientifically accurate depiction of paleoenvironments is achieved it is possible to begin to apply the lessons of the past to the observations of the present. Using the data of how the earth has changed in the past will provide a better understanding of the changes that are happening now. The changes in the past are templates for what causes change and what effect the change will have. Seeing what has happened in the past also demonstrates the process involved in climate change and when compared to modern data can show a clearer image of what is actually effecting the climate. Looking at changes that occur in the record against backdrops of crucial moments on the timeline of the earth history lead to determining specific events as causes.
Having a good understanding of ancient environments also allows for a virtual and physical reconstructions of past ecological settings to provide a basis for managing modern environments. In a paper about Sierra Nevada, California, Millar and Woolfenden(1999) stressed the importance of the environmental history of the area being understood to be able to implement ecological management strategies. Knowing what the environment was like in the past has a profound impact on how it is managed today. Governments around the world manage their natural surroundings in many different ways. Millar and Woolfenden(1999) present a good practical example of why knowing the historical context of an area is as important as knowing the modern context. Providing and demonstrating the way the climate has changed over time gives the ability to make plans for the future.
Prediction of future events is the ultimate goal of studying the climate so that people around the world can be prepared to adapt to new modes of existence. Gathering and combing data on the climate brings researchers ever closer to being able to know that events are going to happen before they happen to minimize potentially harmful impacts on populations worldwide. This is yet another reason that accuracy of description of our global environment is such an important issue. Models for the future need to be based in sound unbiased data. Modeling future conditions solely based on one set of data does not create a reliable prediction. Knowing the past and how it was shaped is the key to knowing the future and how it will be shaped.
Before any decisions are made about the climate around the world it needs to be ensured that the people making the decisions are as well informed as possible. This issue of global climate changes is not only a topic for scientists, but a topic that effects the lives of every person on the planet. As individual economies continue to rely on each other more and more the decisions made by governments around the world are effecting a continuously growing number of people. People everywhere will experience the effects of climate change in one way or another. This issue effects politics, economies and the physical environment that people live in. Because of this the magnitude of decisions made regarding the topic is immense. With so many lives at stake it is essential that as objective and thorough scientific methods are used to create the best solutions. There is no room for fear and sensationalism in global climate change discussions, only the facts. The solutions suggested will need to be as dynamic as the climate itself providing people around the world with a plan for the future climate changes that will occur. It is also very important to keep in mind that the above methods are not the only means to gather information about ancient environments and should never be used as the sole sources of data. In any scientific pursuit it is import to apply as many different methods and gather as much data as possible so that the end result is as accurate as can be. Only focusing on two or three aspects puts a bias on the data which means that the people using the data will not be as well informed as they should be.
References
Alley, R.B. (2003) Abrupt climate change. Science, 299. 2005-2010.
Bachu, Stephan. (2003). Screening and Ranking of sedimentary basins for sequestration of CO2 in geological media response to climate change. Environmental Geology, 44. 277-289.
Blunier, Thomas, & Brook, E. (2000). Timing of Millennial-Scale Climate Change in Antartica and Greenland During the Last Glacial Period. Science, 291. 109-112.
Clark, Peter, Alley, R., Pollard, D. (1999) Northern Hemisphere Ice-Sheet Influences on Global Climate Change. Science, 286. 1104-1111.
Fricke, Henry, & O’Neil J. (1999). The correlation between 18O=16O ratios of meteoric water and surface temperature: its use in investigating terrestrial climate change over geologic time. Earth and Planetary Science Letters, 170. 181-196.
Gutierrez, Mateo. (2005). Climatic Geomorphology. Boston Mass. Elsevier.
Martini, I.P., Martinez, A. & Chesworth, W. (2006). Peatlands: Evolution and Records of Environmental Climate Changes. Boston Mass.: Elsevier.
Millar, Constance, & Woolfenden, W. (1999) The Role of Climate Change in Interpereting Historical Variability. Ecological Applications, 9. (4). 1207-1216.
Monroe, James S., Wicander R. (2009) The Changing Earth Exploring Geology and Evolution. Belmont, CA. Brooks/Cole
Ojala, Antti E.K., Alenius T., Seppä, H., Giesecke, T. (2008) Integrated varve and pollen-based temperature reconstruction from Finland: evidence for Holocene seasonal temperature patterns at high latitudes. Holocene 18. (4) 529-538
Parmesan, Camille. Ecological and Evolutionary Responses to Recent Climate Change. Annual Review of Ecology, Evolution, and Systematics, 37. 637-669.
Peizhen, Zhang, Molnar, P., & Downs, W. (2001). Increased Sedimentation Rates and grain sizes 2-4 Myr ago due to the influence of climate change on erosion rates. Nature, 140, 891-897.
Schumm, S. A., & Lichty, R. (1965) Time, Space, and Causality in Geomorphology. American Journal of Science, 263. 110-119.
Stern, Nicholas (2008). The Economics of Climate Change. American Economic Review: Papers and Procedings, 98. 1-37.
Tank, Ronald (Ed.). (1976). Focus on Environmental Geology. New York: Oxford University Press.
Tucker, Gregory. (1997). Drainage Basin Responses to Climate Change. Water Resources Research. 33. (8). 2031-2047.
Zachos, James, Pagani, M., Sloan, L., Thomas, E., & Billups, K. (2001). Trends, Rhythms, and Aberrations in Global Climate 65 Ma to Present. Science, 292. 686-693.
Filed under: Population, Research Project, Spring 2010, Uncategorized
