Each response was affected differently by the orbital variations, and similarly by greenhouse gas levels. Orbital variations had little affect on annual planetary albedo, while the addition of altered greenhouse gases recreated the albedo pattern found during the LGM more accurately. Changes in both greenhouse gases and orbital variations least effected the annual precipitation. Because the response of precipitation was most similar between the Control Experiment and Primary Experiment 3 it is likely that precipitation is not as heavily influenced by the conditions of the Last Glacial Maximum as the other factors. Annual snow and ice cover patterns could be recreated by altering present day levels of orbital variation and greenhouse gases to …show more content…
Orbital variations had some effect, but not enough to be considered a major factor. While we now know how the patterns came to be, we remain uncertain how the strength in climate changes during the Last Glacial Maximum came to be. What the significance in the forcings’ influence on the response of the intensity of ice sheet growth, low temperatures, and high albedo during the Last Glacial Maximum are still unclear, although, we are certain greenhouse gas levels are important …show more content…
Bouttes et al (2011). We compared maps presenting our main factors (planetary albedo, precipitation, snow and ice cover, surface air temperature) with doubled levels of carbon dioxide alone, or doubled levels of carbon dioxide and methane together. Each and every comparison revealed what little impact methane has compared to carbon dioxide. Globally, surface air temperature average lowered 0.07 degrees C, snow and ice coverage average increased 0.7%, precipitation did not change at all, and average planetary albedo increased 0.02%. These minute changes were nothing compared to the vast changes caused by doubled carbon dioxide, which models we ran to compare the see the effect of extreme variations in greenhouse gas levels. Our research led us to discover that greenhouse gases had a strong impact on the Last Glacial Maximum, and carbon dioxide was the greenhouse gas that specifically caused most of this impact in both warming and, more importantly, in
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 On the contrary, the lecture challenges all the aforementioned theories by passage and believes inasmuch as the outdated information used by passage all those clarifications are merely sheer implausible misconceptions.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.
Increasing greenhouse gas concentrations are expected to have significant impacts on the world?s climate on a timescale of decades to centuries. Evidence from long-term monitoring studies is now accumulating suggests that the climate of the past few decades is anomalous compared with
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.
Scientists have given numerous warnings that human-caused, or anthropogenic, climate change is not only occurring now, but accelerating more quickly than predicted (Maibach, Myers, and Leiserowitz 295). Global warming contributes to climate change as a result of the release of greenhouse gases into the atmosphere (“Global Warming”). The level of greenhouse gases like carbon dioxide, methane, and nitrous oxide in the atmosphere has increased significantly over the years. Patterns of warming are sufficient to conclude that this increase has coincided with the start of the Industrial Revolution (“Global Warming”). By analyzing carbon dioxide pockets that have been trapped in Antarctic ice, scientists can assuredly confirm the correlation between recent warming
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.
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
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 report concludes, again with “high confidence”, that anthropogenic (human caused) warming has had a discernible influence on many of our planets physical and biological systems. While there are limitations and gaps in the knowledge available, particularly from undeveloped countries, the knowledge available allowed the group to attribute most of the observed increase in the globally averaged temperature since the mid-20th century to the observed increase in anthropogenic greenhouse gas concentrations. The analysis was necessarily limited in the number of systems and locations considered. In addition, natural temperature variability is larger at the regional than at the global scale, thus affecting identification of changes due to external forcing and at the regional scale other factors such as land-use change and pollution, are an environmental
If you have ever heard of the Last Glacial Period, you would know that it covered majority of Canada and northern US in a thick blanket of glaciers. When the Last Glacial Period ended and all of the glaciers retracted, it scraped away vast amount of soil and minerals from certain areas of Canada, leaving some areas with rich and fertile soil suitable for farming due to deposits from the ice. However, in other regions such as the Canadian Shield, were left scarred with very thin soil that is no longer sufficient for agriculture. When travelling through the area, I had expected to see a desert created from the desertification of the thin layers of soil. To my surprise, vast amount of trees grow here in the southern parts of the Canadian Shield!
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
Climate change or colloquially known as global warming, now pose a new threat to civilization as the levels of greenhouse gases (GHG) are soaring to new levels. The most significant contributor to greenhouse gasses would be Carbon Dioxide (Co2). The levels of Carbon Dioxide (Co2) gas have risen to levels civilization has not seen before. As such, the effects of these levels are not known to civilization as data gathered from the ice cores drilled in the Antarctica only shows data up to 650,000 years ago. However we can conclude that present CO2 concentrations are higher compared to any time in the last 650,000 years (IPCC 2007). Current carbon dioxide concentrations are hovering around 389 parts per million (ppm) as of September 2011,
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
Figure 1 shows two aspects of the results. The left side displays the information about the amount of greenhouse gases and ozone changes in “500 hPa geopotential height trends (m) are for 1979–2000” (Schindell). The top left shows the computer model predictions while the bottom left shows what existed during the 1979-2000 time frame. The right side of figure 1 shows the “surface air temperature trends (C) are for 1969–2000” (Schindell). Both of these images show the temperatures in the arctic regions are cool and the middle latitude regions are warmer. This is an effect of the changes occurring with the greenhouse and ozone gases.
Current data reveals that the concentration of Carbon Dioxide in the earth's atmosphere is approximately 387 parts per million, which is roughly a 31% increase in the period 1750 to 2009. Consequently, it is evident that such increases in temperatures have caused a warmer planet (7). It is also evident that it is impossible to reverse the developments of industrial revolution. This means that as the advancements of industrial revolution continue and as energy demands increases, it is possible that this trend of climate change will continue for decades to come (McAloon, 8). The consent of the climate research community is that it most likely already affects climate noticeably and will compel significant
Scientists have discovered 'climate forcing’s ' influence variations in climate systems and based on the depth and period of such forcing’s the adjustments to climate may be in a shorter or longer earth cycle. Natural forcing’s like variations in earth 's orbit, solar variation, volcanic eruptions and motion of tectonic plates have influence on the Earth 's climate