Our planet has two glaciers of continental size, one being present on Antarctica and the other on Greenland. Observations made by scientists over the last thirty-five years all agree upon the notion of shrinking, and or retreating of the ice sheets. The melting of ice sheets has powerful implications for the millions of people who depend on glacial melt for drinking water and the millions of people who will be displaced by the sea level rise occurring as a direct result of the melting. The observations of ice melting also show that the rate at which the ice is melting is accelerating. Mountain glaciers around the world are also on the retreat. Some instances of particular mountain glaciers may show expansion, but studies done by glaciologists show that the total mass of glaciers worldwide is decreasing at an accelerating rate. These studies have been done by a number of different methods that all show a trend in the same direction.
The methods by which polar scientists quantify the amount of ice sheet growth or decline took a large leap in the early 1990s when satellite observations began providing spatially comprehensive sets of data. Three separate methods each with particular approaches and limitations have been used to acquire data on ice sheet mass. Satellite altimetry measures ice sheet volume changes from laser and or radar altimeters. This can be converted to changes in mass by accounting for spatially and temporally varying surface density distribution coupled with spatial exploration of unsampled regions. Limitations of this method, similar to other scientific methods lie in the models used. A second method used is referred to as input-minus-output. Through this method scientists calculate the difference between the sn...
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... Earlier research suggested that the ice sheets might grow under climate change due to the increased precipitation from warmer air holding more moisture. As more recent studies suggest, the actual amount of increased precipitation form global warming is countered by the acceleration of ice-flow into the ocean. In all actually stronger snowfall will just increase future ice discharge. Ice-physics simulations have shown that future discharge of ice into the ocean is increased three times due to the additional precipitation. The snow that is piling up due to the increased moisture in the air is exerting pressure on the ice and increasing the rate at which it flows into the ocean. To clarify the notion; more interior snow does not lead to a lack of sea level rise. This has been quantified using several methods that each focused on the grounded portions of the glaciers.
In his essay, “Global Warming is Eroding Glacial Ice,” Revkin is arguing that global warming is constantly changing the ...
Permafrost is permanently frozen soil which hasn’t melted in 2 years or more, it also makes up 24% of the land in the Northern Hemisphere and it stores massive amounts of carbon inside of it (Insert Citation). Permafrost contains large amounts of frozen organic matter and if this organic matter thaws out and starts to decay it will release carbon into the air. As a result of global warming and climate change, permafrost is at risk of melting, releasing the carbon trapped inside, it has been estimated that the permafrost contains 1700 gigatonnes of carbon inside of it (Insert Citation), which is double the amount of carbon in the atmosphere already and there is no way to stop the permafrost melting besides slowing it down by reducing our emissions. Figure 1 shows the northern hemisphere and how much of the land contains permafrost. It can be seen that there is a significant amount of permafrost in the northern hemisphere and if this were to melt there would be a dramatic increase in greenhouse gases in the atmosphere.
“How Dangerous are Glaciers?: Glaciers Have Their Own Warning Signs.” Alaska Satellite Facility. University of Alaska Fairbanks, 2014. Web. 17. Feb. 2014.
Various glaciers in Alaska and other parts of the United States have shrunk dramatically. If temperatures continue to rise, the ice will continue to melt, and some glaciers could disappear completely, which causes sea levels to rise. There are many animals, birds, and seafood that depend solely on glaciers for survival. With an increase in sea water temperature, and increasing sea levels, sea-plants that these fish thrive on will be lost, lowering the number of seafood, which in-turn will make survival of many species difficult. The arctic is source region for cold ocean currents and with no ice it will have no density and temperature distinctions, which pushes the ocean currents. If the ocean current heat transfer mechanism powers down,
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 numerous ice ages documented on this planet that have shaped its contours, offers us incredible insight on many of the factors that have made this planet the way we see it today. But the great thing about glaciers and ice caps being much older than the human race, is that scientists are able to distinguish much information and characteristics of the past. And by understanding the past, we gain a much better perspective of the future: what we h...
The Himalayan mountains are home to the second largest body of ice in the world, these glaciers are extremely important to the lives of many people, animals and ecosystems.The Himalayan range includes about 15,000 glaciers, which store about 12,000 km3 (3000 cubic miles) of freshwater. The Himalayan mountains are located in the northeastern part of India and pass through several countries including Pakistan, China, Afghanistan, Nepal and Bhutan. The glaciers in the Himalayan mountains are at the headwaters of many essential and large rivers throughout the himalayan and asian countries. Over the last 30 years some glaciers in the Himalayas have retreated one kilometre. The negative effects of CO2 and global warming on the glaciers have caused the glaciers to melt, or retreat having a lot of drastic effects. Over time, as a result of glacier shrinkage, normal glacier melt will not be able to contribute to the Himalayan region's water supply each year. Water availability will not be affected at low elevations because they are mostly dependent on monsoon rains, however at higher elevations glacier retreats will result in streamflow alterations in some basins.
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 aspect of climate change impact on environmental phenomena can be revealed.
Some scientists believe that the continent is shrinking as a whole, while others believe the opposite. "The polar sea ice paradox is really a challenge for the science community," NASA research scientist Son Nghiem said in a recent interview. The melting is clearly evident, take the vast Larsen C ice shelf for example. A 5,000 sq miles just recently broke off its peninsula, the size of Trinidad and Tobago or a quarter size of Wales. It has been linked to global warming, but this does not explain the growth of the continent.
The Earth has been experiencing a warming period for the past 30 years indicating that a cooling period is about to occur. There are several factors that contribute to climate change including a rise in the temperature such as the Earth’s tilt, tectonic plate changes and volcanic activity. A shi...
In the findings by Thompson, Brechera, Mosley-Thompson, Hardy, and B. G. Mark, they discovered that “of the ice cover present in 1912, 85% has disappeared and 26% of that present in 2000 is now gone”. They traced the receding ice back to the early 20th century, beginning in 1912, where “summit ice cover (area extent) decreased ~1% per year from 1912 to 1953 and ~...
However, climate change is happening. The global average land and sea temperature has increased over the twentieth century, with the North and South Poles being particularly affected (Learmonth, et al., 2006). In turn, this has caused ice cover to decrease and sea levels
Jacob, T., Wahr, J., Pfeffer, T. W., & Swenson, S. (2012). Recent contributions of glaciers and ice caps to sea level rise. Nature, 514-518. http://dx.doi.org/10.1038/nature10847
It is an unquestioned fact that the climate is changing. There is abundant evidence that the world is becoming warmer and warmer. The temperature of the global land average temperature has increased by about 8.5 degrees centigrade from 1880 to 2012 (Karr, et al 406). The one or two degrees increase in temperature can cause dramatic and serious consequences to the earth as well as humans. More extreme weather occurs, such as heat waves and droughts. The Arctic Region is especially sensitive to global climate change. According to the data in recent decades, the temperature in the Arctic has increased by more than 2 degrees centigrade in the recent half century (Przybylak 316). Climate change has led to a series of environmental and ecological negative
Glaciers have disappeared due to increasing in global temperatures because of which the water level had drastically increased and its causing flood all over the world