Snowball Earth Hypothesis

We all know that atmosphere is continually evolving. We have had ice ages and hotter periods when gators were found in Spitzbergen. Ice ages have happened in a hundred thousand year cycles for the last 700 thousand years. There also have been time periods that seemed to have been hotter than the present in spite of CO2 levels being lower than they are currently. Overall what I am saying is that we have had the medieval warm period and the little ice age. Because of these evolutions there has been different effects on the earth.

Earth has experienced many episodes of dramatic climate changes with different periods in earth history. There have been periods during which the entire planet has been covered in ice and at another time it has been scorchingly hot and dry. In this regards, earth has experienced at least three major periods of long- term frigid climate and ice ages interspersed with periods of warm climate. The last glacial period which current glaciers are the result of it, occurring during the last years of Pleistocene, from approximately 110,000 to 10,000 years age (Clayton, 1997). Indeed, glaciers present sensitive indicators of climate change and global warming and by estimating and monitoring the dynamic evolution of these ice masses, several

The Late Pleistocene period was when the final glacial episode of ice sheets covered much of the northern hemisphere. This event happened about 125,000 years ago and lasted

The glaciation is very confusing to those who don't know about glaciers so here is some background information. The last glacial advance started about 75,000 years ago and the last

Ice ages are well documented in Earth’s history, and they are proven to be relatively frequent. But what if that ice age persisted over not just regions near the poles, but around the equator as well? The term “snowball Earth” refers to a condition where Earth is completely covered by ice. Evidence indicates that snowball Earth may have been around in the Neoproterozoic. In fact, evidence points to the conclusion that these conditions happened three separate times in the Neoproterozoic. A snowball Earth condition is hard to prove, but this theory may explain several different phenomena. However, it is not accepted by all, there is evidence against a snowball Earth as well. Some believe that a snowball Earth would not have been possible in past climate conditions while there are views that defend the idea of more of a ‘slushball’ Earth rather than a planet entirely frozen on the surface.

The passage declares numerus reasons in hope of justifying the real causes of Little Ice Age existence during 1350 till 1900 CE. On the contrary, the lecture challenges all the aforementioned theories by passage and believes inasmuch as the outdated information used by passage all those clarifications are merely sheer implausible misconceptions. In what follows, three major hypotheses and their critics will be delved into nut briefly.

There have been at least five major ice ages in the pass one billion years. The most recent was called the Pleistocene Ice Age, which began about two million years ago. Interglacial periods occurred where temperatures increased slightly and the glaciers would melt and retreat.

It is theorized that during the latter part of the Cenozoic era, also known as the age of mammals that the Wisconsin glaciation caused enough of the planet’s water

and come apart and allow for countless sheets of lava to be transferred out over the land (Hay, 1992). Through time the ice caps frequently collected and spread over enormous extents in North America. In this timeframe, movements to the south would occur making the ice push and relocate expansive quantities of soils and rocks. This movement effected how the great glacial streams would flow (Hay, 1992). With the extremely large rains and glacial ice melting valleys and flooding played a great role in the Pleistocene.

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,

The true impact of “The Little Ice Age” began around 1600 and lasted until the 1800’s. During that time in Europe is when it was at its height. It was considered to be the most significant climate event of the last millennium. Only until recently have climatologist discovered research of climate conditions in historical times. As stated before, no one is quite sure how “The Little Ice Age” evolved. Climatologist and historians have had many discussions on what they think was the main cause of the ice age. Today they are able to determine the yearly average temperatures, rainfalls, volcanic activity, and the effect of the sun during that period . What we know is that the sun experienced a “quiet” period, meaning its intensity was not that strong. Therefore, a cooling occurred. Sunspots which determine the suns strength were noted to be in decline. Volcanic activity is to be another known source of the cause. As the volcanoes erupted they shot out particles and gases into the air. With these gases floating in the

Glaciation that are widespread can be identified based on the subglacial tillite, which is a thick layer of sediments that settle down beneath glaciers or ice caps. On top of this subglacial tillite layer is deposited marine carbonate, also known as cap carbonate. Based on their paleolatitude designated by glacial sediments’ paleomagnetism, it can be determined that these deposits are from equator region. The interaction between two types of sediments, marine (like carbonate) and subgacially deposited sediments, indicate that the glaciers had approached marine coastlines.

Glaciers are one of the most fundamental phenomenon on the planet, and much of their purpose and impact on earth has been well documented and published. Ice sheets, Ice Caps and Glaciers trap nearly 90% of the world's fresh water, and are replenished by snowfall each year. Their existence on this planet dates back 650,000,000 years and yet they are always moving, always shifting and always melting. Before, human existence and even during the brief era of humans, ice dominated all of the earth's landmass and have regulated, created and altered many of the landscapes around the world.

The Medieval Warm Period (MWP) refers to a relatively warm period lasting from about the 10th to the 14th century.2 However, the initial evidence for the MWP was largely based on data3 gathered from Europe, and more recent analyses indicate that the MWP was not a global phenomenon. A number of reconstructions of millennium-scale global temperatures have indicated that the maximum globally averaged temperature during the MWP was not as extreme as present-day temperatures and that the warming was regional rather than global. Perhaps the most well-known of these is that of Michael Mann and colleagues (Nature, 392, 1998, pg. 779). Their reconstruction produced the so-called “hockey stick” graphic that contributed to this conclusion in the 2001 assessment of the Intergovernmental Panel on Climate Change: “The…'Medieval Warm Period' appear(s) to have limited utility in describing trends in hemispheric or global mean temperature changes in past centuries." The accuracy of the “hockey stick” graphic was widely discussed in the press when the Mann et al. methodology was criticized by McIntyre and McKitrick (Geophys. Res. Lettr, 32, 2005, pg. L03710). Less attention was given to subsequent studies, such as that of Moberg and colleagues (Nature, 433, 2005, pg. 613) and Osborn and Briffa (Science, 311, 2006, pg. 841) that were based on different, independent methodologies but reached conclusions similar to Mann. Observations of melting high altitude glaciers are

Soon after the birth of earth, it was a very different place from the one we know today.