The Human Impact on the Global History of Climate Change
A Research Paper by Justin Slater Are humans responsible for the destruction of their habitat also known as Mother Nature? Human-made pollution is obvious; from trash in local streams and rivers to plumes of carbon dense smoke billowing out of power plants; it has become quite clear that sustainability is not a priority. Also, our resources are being used and abused much faster than the earth can replenish and recover. Within the past 10 years this abuse of Mother Nature has become a topic of great interest.
This interest has been labeled as the “green movement,” and it advocates stress awareness of waste and pollution and includes its effect on the environment. The most publicized consequence of our non-earth friendly actions is global warming. This theory is blindly adopted with little scientific evidence because it justifies the worlds’ need to “go green. ” When the overwhelming facts concerning greenhouse gasses, and the sheer amount of waste humans produce is taken into account, there is no wonder global warming is justified in peoples’ minds.
Over the past 150 years human activities have released increasing quantities of greenhouse gases into the atmosphere. This has led to increases in mean global temperature, or “global warming. ” Other human effects are relevant—for example, sulphate aerosols are believed to have a cooling effect. Natural factors also contribute. According to the historical temperature record of the last century, the Earth’s near-surface air temperature has raised around 1. 3 ± 0. 32 ° Fahrenheit (Wikipedia, 2012).
Although human induced global warming is a popular theory, it is misleading because climate change has occurred throughout history, our most recent period of warming ended over ten years ago, and the earth is currently in a state of cooling. The scientific truth is that climate change is nothing new. In the life span of the Earth, a climate where humans could have inhabited the planet is mere smudges on the planet’s climate time-line. Starting with the big bang over 13. 7 billion years ago, the earth has experienced cycles of hot flashes and freezing spells (Sorokhtin, Chilingar, and Khilyuk, 2007, p. ). As recently as 650 million years ago the earth was frozen solid. This period of 10 million years is known as “Snowball Earth”. After this period, volcanoes began to erupt which produced greenhouse gasses that naturally warmed the earth. Over the next 400 million years, global temperatures rose and fell allowing for small life forms to succeed. Plants, cold-blooded animals, and insects did well during this time (Hulme, 2009). Then, quite suddenly, there was a mass extinction. Over 95% of the earth’s species died due to flood basalt eruptions lasting for one million years.
The earth’s temperatures rose an impressive 18 degrees F due to a 700% increase in carbon dioxide during this time. It then took 195 billion years for the blanket of carbon dioxide to dissipate and the earth to cool (Kohler, Bintanja, Fischer, Joos, Knutti, Lohmann, and Masson-Delmotte, 2010). The time spans of these major climatic events far surpass any current data time frames. In comparison to a human life span, the earth moves at a snail’s pace. Any temperature fluctuations observed currently are not significant enough to say that humans have impacted the current natural occurrence.
At about 55 million years ago another 20 degrees F increase occurred due to increased methane gas. Over the next 40 million years, temperatures continued to fluctuate, allowing for the polar ice caps to expand and retreat. Since this last temperature change, the climate has stayed relatively stable with an ice age occurring in between every 10,000 years. When temperatures warmed, woolly mammoths and other mega mammals that thrived during the ice age could not survive, while humans were able to adapt (Marsh, 2007). However, it would be ignorant to think climate change would miraculously come to a stop on behalf of human inhabitation.
The above-mentioned changes had drastic effects on the Earth. Recently there have been less drastic, though still noticeable, climate fluctuations. The most recognized examples of modern climate change are known as the Medieval Warming Period and the Little Ice Age. The Medieval Warming Period (MWP) took place between 800 and 1300 AD, and consisted of temperatures up to 5 degrees F warmer than today. It is the most recent phase of warming before the industrial era in the 19th and 20th centuries. These temperatures played a huge role in human history, as it was what partially allowed the
Vikings to colonize Greenland. Although it is currently being debated, this period of warmth could have been global (Qlan, Burns, Solomon, and Roble, 2009). If so, the slightly elevated temperatures seen over the last thirty years would not be unprecedented. In fact, they would be quite normal and expected. Following the MWP was the Little Ice Age (LIA). This period consisted of three consecutive cold spikes with slightly warmer periods in between. These spikes occurred at about 1650, 1770, and 1850 AD and are well documented in North America and Europe.
As with the MWP, it is debatable whether these were global events (Mathews, Weaver, Meissner, Gillett, and Eby, 2004). At this time the sun was virtually free of sunspot activity. A correlation between temperature and sun spot activity known as the Maunder Minimum developed with help from observations from that time (Trenberth, 2009). Not only do these historical events contradict the current theory of human-made global warming, the research gained from these events brings to light other justification for naturally occurring climate change. The justification being that it just happens.
There are many scientific explanations for what causes temperature fluctuations such as sun spot activity however, what reduces or increases the amount of sun spots themselves is unknown. There is no doubt the earth has, and will continue to experience periods of warming. Our most recent period began in the 1900s and lasted through the year 2000. This warmth can be accredited to our sun that was the brightest it has been in over a 1,000 years (Michaelowa, 2009). This increase in brightness did not happen over night; instead it was a result of over 100 years of activity.
This increased brightness is due to sunspots. It is not clear as to the correlation between sunspots and climate change, however a rough assumption is that the more sun spots there are, the brighter it is, and therefore more heat is produced (Melezhik, 2006). In addition, sunspots create a magnetic cycle that has been found to correlate with the Northern Hemisphere land temperatures (“Global Warming”, 2004). The important thing of note is the date attached to the above data. At this time the earth was in fact warming. Since the early 2000s, data has shown the earth is once again cooling.
According to NASA, sunspots are on the decline: out of the 365 calendar days in 2008, 266 where sunspot free. This was thought to be an all time low since 1913, however an awesome 87% of the days of 2009 were sunspot free. The graph accompanying the article depicts a peak in solar activity right around 2000, with a sharp decline predicted through 2012 (“Deep”, 2009). So far, this activity chart mimics that of the observed temperature fluctuations. The current lull in activity also allowing scientists to better understand what a deep solar minimum is like first hand. Other studies have found similar evidence.
In the journal Energy Sources, Part A: Recovery, Utilization, and Environmental Effects a study was published analyzing the affects of carbon dioxide and the atmosphere. The scientists concluded the short-term temperature variances scientists have observed over the past 100 years cannot be accredited to fluctuations in carbon dioxide. Instead they are positively matched with sun spot activity Chilingar, Khilyuk, and Sorokhtin, 2008). The recent cooling and previous period of warming are considered short-term temperature changes, and cannot be cited for significant data. However, events such as the Little Ice Age have more historical bearing.
Five hundred years is a much more substantial duration of time yet still trivial in comparison to the earth’s first ice age of one million years. As the world’s reliance on fossil fuels increases, so do the byproducts of consumerism. Ever increasing amounts of carbon dioxide and other greenhouse gasses are being admitted into the atmosphere as more cars are on the road and more energy is being produced. According to computer simulations, the earth’s temperature should have increased 1. 8 degrees F over the last 100 years based on the amount of carbon dioxide being released. This has not been the case however.
Fluctuations have been smaller, staying with in . 5 of a degree (Baliunas, 1999). Previously, carbon dioxide billowing out of volcanoes was responsible for drastic temperature changes. At times the earth was more than 20 degrees F warmer than it is now. This is poor support for global warming theorists, the volcanic eruptions responsible for the warming occurred over the course of thousands of years. These endless eruptions covered the majority of the earth in molten lava (Marsh, 2007). This scene is unfathomable for humans, and is in no way comparable to the current levels of carbon dioxide found in the atmosphere.
The current levels of carbon dioxide are approximately 390 parts per million. This number has increased over the years, however when compared to other levels in history it is not alarming. During the Triassic Period, when dinosaurs roamed the earth, these low levels would have resulted in a much earlier extinction. Carbon dioxide is plant food, an abundance of it, approximately 1,560 to 1950 ppm, resulted in robust vegetation for these large animals to devour (Diffenbaugh, 2009). Humans know the benefits of this gas as well. Many botanists swear talking to their plants is the key to health.
Though the plants cannot hear, they are very happy to absorb the carbon dioxide given off during the action of talking. It is clear there is little concrete scientific evidence to support, or deny global warming. What can be confirmed is that climate change is inevitable. Some studies have gone as far as to say the increase in carbon dioxide leads to cooling, not warming. This conclusion has a simple physical explanation: when infrared radiation is absorbed by green house gas molecules the air expands which causes circular fluxes of air masses restoring the temperature in the troposphere.
The small amount of carbon dioxide released into the air by humans is not enough to influence the atmospheric temperature of the Earth (Cooling of Atmosphere, 2008). If this subject is studied further and found to be true, there is no doubt a wrench will be thrown in this crucial argument. With compelling, yet questionable evidence for those who agree and disagree with the theory of global warming, there is no doubt that the debate will continue as more research is preformed and time goes on. Dr. Bell believes global warming is the greatest ruse known to modern science.
It is debatable how the rumor became so large with such little evidence; however it is quite clear the opposite would be a much greater threat. Food, people and animals can survive in extreme heat with food and water; the same does not go for life in extreme cold. The essentials to life: food and water would be locked away under ice, crops unable to grow and animals unable to eat (Bell, 2007). This is a much scarier thought for humans to comprehend. Some scientists even feel this is one of the reasons global cooling research is so heavily scrutinized and disclaimed.
It is apparent the prevailing research and theories on the subject are not willing to be challenged. There is no question global warming is a complex issue, however it is nothing new. Throughout history, extreme climate has been normal. Regardless of what human kind has done by way of contamination, the Earth will continue about its climate cycles without batting an eye. Human life is a fluke, developed from ideal conditions in an inhabitable environment. Humans are but insignificant guests in this world who have failed to respect their hostess.
They have polluted and contaminated the environment, but the Earth will keep moving on. The current climate fluctuations are not significant enough for one to use to draw conclusions. Be it another ice age or incinerating heat, the tectonic plates will shift, the volcanoes will erupt, and over millions of years people will be but a memory. However, humans are the Earth’s current inhabitants. To continue to live, sustainability must be kept in mind. Research is contradictory on the subject of climate change; however, there is no denying that the earth is its own entity, unbound by the actions of humans.