In the nineteen-teens, as World War I raged across Europe, Milutin Milankovic, a Serbian astronomer and prisoner of war, was busy computing the gravitational force of planets like Jupiter on the Earth’s tilt and orbit. He had an idea that the amount of solar radiation that reaches higher latitudes could trigger an ice age or warm up the Earth. He believed that slow changes in the Earth’s orbit contributed to the amount of solar radiation reaching a particular latitude. By the end of the war, his first paper was published on the subject, and he began to expand upon his initial ideas. In 1941, he published Canon of Insolation of the Earth and Its Application to the Problem of the Ice Ages, describing his theories about the Earth’s orbit and tilt which are now referred to as the Milankovitch Cycles.
There are three main tenets of the Milankovitch Theory:
• the tilt of the Earth, or its obliquity
• the ellipticity or eccentricity of the Earth’s orbit
• the precession of the equinoxes.
Milankovic’s theories were initially ignored. Then in the 1970’s, scientists showed a renewed interest, and now the Milankovitch Cycles are widely accepted as contributing to the cycles of the ice ages although they continue to be critiqued and revised.
Obliquity—The Tilt of the Earth
We all know that the tilt of the Earth accounts for the seasons, but many folks don’t know that the tilt, or obliquity, of the Earth has changed over time. During a period of 41,000 years, the tilt of the Earth’s axis changes from 22.1° to 24.6°. This wobble, like other facets of the Milankovitch Cycles, is caused by gravitational interactions with other planets.
Currently the tilt of the Earth’s axis is 23.4°, but 9,500 years ago whe...
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...stocene epoch, we find that the temperature cools by four to ten degrees every 40,000 to 100,000 years and then warms back up again.
This is good news for Milankovic, but there are two problems.
• When conditions are favorable for an ice age in the northern hemisphere, they’re not favorable for one in the southern hemisphere. How could the Milankovitch Cycles cause a global change in climate then?
• Milankovitch cycles can only account for a temperature difference of 1° to 2°. How is it possible then that sediment records show temperature differences of 7° to 10°?
Currently, scientists believe that once an ice age has been triggered, oceanic circulation currents can change and the mixing of the oceans cools the southern hemisphere. As glaciers begin to accumulate in the northern hemisphere, solar heat is reflected off the snow which leads to further cooling.
People are responsible for higher carbon dioxide atmosphere emissions, while the Earth is now into the Little Ice Age, or just behind it. These factors together cause many years discussions of the main sources of climate changes and the temperature increasing as a result of human been or natural changes and its consequences; even if its lead to the global warming, or to the Earth’s cooling. In their articles, “Global Warming Is Eroding Glacial Ice” by Andrew C. Revkin and “Global Warming Is Not a Threat to Polar Ice” by Philip Stott, both authors discuss these two theories (Revkin 340; Stott 344). Revkin is right that global warming is taking place. Significant increase of carbon dioxide in the atmosphere is due to human activities combined with natural factors such as volcanic emissions and solar radiation – all together they lead to climate changes and temperatures rising. At the same time, other factors such as deforestation contribute to environmental changes for some glaciers not less than air pollution. However, during global warming not all regions of the planet are affected in the same way, local warming and cooling are both possible during these changes.
The earth is about four billion years old, within the span of these four billion years; the earth has become accustomed to various transitions and dissimilar geological and environmental permutations. The Ice age period has been the subject of much debate regarding these various transitions. As the rate at which geological disasters on earth continue to intensify we begin to ask ourselves whether it is possible for an ice age to spontaneously occur overnight. Nonetheless, In order for such a disaster to persist, massive improbable geological events would have to occur and graft coherently which is evidently and scientifically impossible. The notion that an ice age can occur overnight is implausible for the reason being that: Global warming is on a evidential rise , chances of catastrophic volcanic activity as deteriorated and the earth's orbit is at a period of solar radiation absorption.
The Little Ice Age is the name for the period of cooling spanning from 1400 to 1900 c.e. that took place after the Medieval Warm Period. Scientists believe that solar minimums and reversals in the Northern Atlantic Oscillation, a large atmospheric-circulation system that affects weather in the North Atlantic area including Europe, drove these changes (Encyclopedia Britannica, 2014). It is often assumed that the Little Ice Age had a global impact. However, in 2001, the Intergovernmental Panel on Climate Change put forth in a climate assessment report that though there were glacial increases in other parts of the world, they were not synchronous with the glacia...
Finally, the moment you have all been waiting for, the third paragraph! This is where I will persuade you to believe my ideas. Well, here it goes. My final idea is that the globe is now recovering from a time know as the little ice age. This in turn will make the earth seem warmer. In science class, we conducted an experiment conducting this. We put one hand in warm water and another in cold water. Then we put both hands in room temperature water. The hand that was in warm water felt cold and visa vera for the other.
Scientists are currently having a great debate; are the arctic storms at lower latitudes normal weather patterns? Or are they happening due to human activity? The effects of climate change are reshaping weather patterns all over the g...
The fluctuating tides based on density levels, salinity, surface heat and freshwater amounts available is defined as thermohaline circulation, also known as the great ocean conveyor belt. In colder areas, and Polar Regions, the warmer surface water becomes cool enough and dense enough in salinity to sink the bottom of the ocean and pushes the deep water into shifting and rising. It is postulated that an outpouring of fresh meltwater upset the salinity balance of the surface water, preventing it from becoming dense enough to sink and stopping the thermohaline circulation, caused the world to be catapulted another Ice Age. A research team of University of Sussex, commanded an expedition to study the gravel and boulder deposits from the Mackenzie River basin as well as the Athabasca Valley for clues or indications of meltwater travel. These physical structures do indeed suggest that there were two floods, one of which is estimated to coincide with the approximated timing of the flood that slingshot the northern hemisphere into glacier
Climate change is difficult to express directly, for knowledge of climate change generally falls under the classification of “weather.” However geologists have known since the mid-nineteenth century that local, and global climate undergoes change throug...
The Eocene Epoch ended about 35 million years ago allowing the third epoch of the Cenozoic Era, the Oligocene, to begin. The end of the Eocene Epoch can be considered to be a facto of the plate movement observed above. Not only did the plates move but they also resulted in a distinct change in the temperatures observed in the atmosphere. The average temperatures suddenly cooling caused the overall climate to leave the moist, subtropical level and become very dry. The ice caps returned to the North and South Poles of the Earth. This form of cooling affected many organisms causing them to become extinct but also allowing for different types of habitats, like woodlands, to be made.
Throughout history climates have drastically changed. There have been shifts from warm climates to the Ice Ages (Cunningham & Cunningham, 2009, p.204). Evidence suggests there have been at least a dozen abrupt climate changes throughout the history of the earth. There are a few suspected reasons for these past climate changes. One reason may be that asteroids hitting the earth and volcanic eruptions caused some of them. A further assumption is that 22-year solar magnetic cycles and 11-year sunspot cycles played a part in the changes. A further possibility is that a regular shifting in the angle of the moon orbiting earth causing changing tides and atmospheric circulation affects the global climate (Cunningham & Cunningham, 2009, p.205). Scientific studies suggest that all these played a role in past global warming and cooling periods. Today, however, there is a lot of conflict on whether humans are causing a global warming that could be disastrous to humans and all species of plants and animals on this earth. This paper will first explain the greenhouse effect, then take a look at both sides argument, and, finally, analyze the effect of global warming on world-wide sustainability
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The climate on the Earth is changing. Ice age is interleaved with the global warming. In the present age, the temperature of the Earth's climate system continues to rapidly increase and it leads to global warming. Global warming is the process of gradual growth of average annual temperature of the atmosphere of the Earth and World oceans. The average temperature on the Earth was increased by 0.6C. There are various reasons for global warming, such as human activities, natural events, increasing of gases, such as carbon dioxide in atmosphere and solar activity (Global warming).
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earth?s atmosphere starts to warm, which leads to global warming. Global warming can lead to
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While critical of global warming alarmism, this documentary does not doubt that the earth is warming. Instead, they claim that scientific evidence demonstrates that such warming is but a natural variation in earth’s climatic history, similar to the Medieval Warm Period of the Little Ice Age. The documentary uses several lines of evidence to back up this claim, including ice core data that they claim when rightly interpreted shows carbon dioxide as having a lag time when earth’s climate has warmed in the recent and distant past, making it doubtful that it could be responsible for the increase in temperature that has been observed recently. The timing of the recent warming, which was most pronounced in the late Nineteenth Century through World War II, stopped and reversed to a cooling trend in the mid-Twentieth Century, and then rapidly warmed again in the past three decades, is dissected. Since this warming began before the advent of major human sources of greenhouse gas emissions and the period of most dramatic industrial...