Snowball Earth Hypothesis Essay

Roughly 2.4 million years ago, the Ice Age began on Earth. Over time, the thick snowpack that had accumulated in the Sierra Nevada due to cooled temperatures compacted into giant sheets of ice. These ice sheets became glaciers when they were set into motion due to the pressure of their own weight. The glaciers cleared everything that came in their path including boulders, soil, and trees; everything but the bedrock, which was instead smoothed out, was completely stripped. As global temperatures fluctuated over the years, the glaciers have advanced and retreated multiple

Annotated Bibliography Capra, L. (2006). Abrupt climatic changes as triggering mechanisms of massive volcanic collapses. Journal of Volcanology and Geothermal Research, 155(3), 329-333. This article explains how volcanic collapse can affect the climate.

They assess major historical events using two pieces of criteria: the presence of a geological marker, and a geological shift in the earth’s system. To evaluate these events, they present graphs and tables, as well as reference other scientists and their respective studies. Not only do Lewis and Maslin successfully

Surprisingly, the clay held almost 30 times more iridium than the limestone layers above and below the clay. Similar layers in other parts of the world gave the same results. The conclusion was that a giant meteorite hit the Earth 65 million years ago and had released a large

According to the geological and paleontological evidence gained from iron formation, paleomagnetism, and cap carbonates, the globe went through a period of glaciation. The original theory Snowball Earth, proposed that the globe was once covered entirely with ice or snow from poles to the equator. As most of the continental mass was near the equator there was a heightened silicate weathering that resulted in “higher equatorial albedo” and carbon-dioxide “drawdown” which led to global cooling and sea ice expansion (1, 3).

IRTC spoke with Detective Jones who reported that she responded to Montefiore Hospital and was able to observe the subject child. Detective Jones conveyed that ECS also made a visit to the Montefiore Hospital to observe the subject child. Detective Jones stated that she spoke with medical staff who confirmed the subject child’s injury but also stated that it is a common injury which could happen to a child when they are learning to walk. Detective Jones conveyed that she has some questions regarding the child’s mother not noticing the injury until the next day, but it is difficult to say when and injury was initially visible if you’re not looking for it. Detective Jones added that when the subject child was observed at the hospital, the injury

Some scientists have attributed the extinction to an extraterrestrial event. In 2009, another group of scientists found nanodiamonds in the sediment layer dating back to the Younger Dryas a period of glacial dewarming. Because these nanodiamonds needed conditions similar to that of cosmic impacts to form, they concluded that a large group of comets might have impacted the Earth, causing the Pleistocene extinction (Kennett et. al, 2009). Although the research done on late Pleistocene extinctions was extensive, the conclusions for these explanatory models contradicted one another.

The Northern Hemisphere Glaciation (NHG) is believed to have initiated into large scale, permanent ice sheets ~2.5 Ma, which is almost 31.5 Ma after the initiation of the Antarctica ice sheets. There are many possible causes for the onset of this climate event, some of which we will be reviewing in this essay. In this essay we will look at the cores from IODP and ODP sites 302, Arctic Ocean; 913, Greenland basin; and 907, north of Iceland, in order to identify the characteristics and possible causes of the northern hemisphere glaciations. First we will look at the evidence for the onset of this event and the proxies

Maximum glaciations during the last ice age, took place about 18,000 years ago, and this reference preceded the ice!

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,

Around 720 million years ago. A bunch of the Earth was covered in ice. It lasted a lot of years. There were so many explosive underwater volcanoes. They were a major thing to have to do with this thing called a "Snowball Earth." They call it a "Snowball Earth" according to new research.

Another was the formation, about 3 million years ago, of the Isthmus of Panama, which connected North and South America and diverted the oceans’ circulation t a more northward pattern. Since the first northern-hemisphere glaciers formed, 2.6 million years ago, the polar ice caps have expanded and contracted in response to variations in the Earth’s orbit around the Sun, causing cold spells alternating with warmer periods, like the one we live in now. There is no reason to believe that another Ice Age won’t come. In the past, warm cycles lasted about 10,000 years, and it’s been that long since the last cool period. Human-made pollutants may also have an effect on the Earth’s climate cycles. The Pleistone period was between 2 million and 10,000 years ago. This was the time of the “Ice Ages,” when climates alternated between conditions similar to those of the present day, and periods when great glaciers spread over large parts of the Earth. Between 15,000 and 10,000 years ago, many large mammals, including saber-toothed cats, ground sloths, mammoths, and mastodons, became

11,700 years ago the geological epoch the Holocene was thought to of began following the Pleistocene epoch, together these time periods make up the Quaternary period. The Holocene has been described as being relatively warm and with a fairly stable climate. Not only this, but it is thought to coincide with the start of agriculture as human populations rose throughout the Holocene technology became more sophisticated aiding the rise of agriculture (Holden, 2012). The early anthropogenic hypothesis was published in 2003 by Professor W.F. Ruddiman, this was a three part hypothesis in which Ruddiman proposed humans reversed natural decreases in CO2 values within the atmosphere by deforestation. That they reversed natural methane decreases after 5,000 years by irrigating rice, they also caused a warming sufficient to prevent a new glaciation within the last several thousand years and during the Holocene (Ruddiman 2005). This hypothesis has attracted a lot of attention with many people both supporting it and criticising it. Throughout this essay I will be exploring the many arguments for and against the early anthropogenic hypothesis and stating whether or not human kind could have prevented the start of an ice age during the Holocene.

The Pleistocene Epoch is usually recorded as the geological time period that commenced ~1.8 million years ago and lasted until ~11,700 years ago (Zimmermann, 2013). The Pleistocene Epoch experienced an escalation towards global climatic cooling (Sytsma, 2011), with series of glacial and interglacial periods in which large areas of the Northern and Southern Hemisphere were under the cover of thick ice sheets. At first, many scientists thought that there were about 4 major ice ages in this Epoch. However, as proxy data improved, and scientists were able to use deep ocean δ18O isotope records to review historic temperatures, they have calculated that there have not just been these 4 ice ages, but dozens (Battersby, 2010); some records suggests

A rose fragrance proves the reality of rose; similarly, the humanity visualizes the human. Otherwise, both fail to be a real one. A rose fragrance proves the reality of rose; similarly, the humanity visualizes the human. Otherwise, both fail to be a real one.