Реферат: Glacird Essay Research Paper Topic 1 Glaciers1What
Glacird Essay, Research Paper
Topic 1 Glaciers
1.What is a Glacier?
A glacier is a big moving mass of ice; it is formed in high mountains or high latitudes where the amount of snowfall is higher than the melting rate of snow.
2. How do glaciers differ from ice shelves, icebergs and sea ice?
Glaciers are huge and they also have a granular structure. Glaciers change the shape and the land though they?re slow but significant movement. Ice shelves are floating masses of ice that are attached on at least one edge of the coast. Sea ice is seasonal ice during, during the summer there is less than in the winter. Icebergs are huge chucks of glaciers; they are also seasonal so they change with the climate.
3. How much glacier ice is on earth?
There is over fifteen million square kilometers of glaciers covering the earth?s surface.
4. How do glaciers form?
Glaciers are formed when there is more snowfall than evaporation. If the snow from the winter does not melt during the summer the next winter will snow on top of the pervious winters snow, which keeps building up creating glaciers.
5. How do glaciers change the landscape?
A glacier moves across the earth?s surface it slowly caries and shapes new landscapes. The huge mass of the glacier allows it to pull up large boulders from the bedrock layers of solid rock beneath the lose rock fragment carry them along. All glaciers change and shape the land through there slow but significant movement.
6. Describe the ice sheets of Antarctica?
The ice sheets in Antarctica lie below sea level in some locations, there is 1.24 miles of ice below sea level. There are bigger and thicker sizes, they also cover 10 million square miles in the west Antarctica.
7. What are ice ages? Compare the extent of glaciers during the last ice age with the extent today?
The ice ages were around 100 million years ago, and it was the intervals of time when large areas of the earth were almost covered by ice. The ice ages took place during the Quaternary period. Today the glaciers are much smaller then they were in the ice ages.
Nixon, Hershell H., Joan Lowery Nixon. Glaciers, Natures Frozen Rivers. Dodd and Mead Co. New York, 1980.
Topic 2 Degassing of Co2 near Mammoth Mountain
1. Where is Mammoth Mountain?
Mammoth Mountain is located in the Sierra Nevada Mountain in eastern California. It sits on the edge of the Long Valley Caldera.
2. What is the Long Valley Caldera?
Long Valley Caldera is a large complex of volcanoes. (A row of volcanoes together) The volcanoes have been active for millions of years there is also earthquake activity and ground uplift in the recent years.
3. What has been happening to trees in the Long Valley Caldera since 1990?
First noted in 1990 the areas of tree kill now total about 170 acres in six general areas. CO2 is coming to the earth?s surface and kill all of the trees. It is taking all the oxygen away from the trees.
4. What is casing the phenomenon described in your answer in #3?
Toxic levels of CO2 are rising up to the surface and it is killing the trees. The reason its happening is from the high levels toxic levels of CO2 is taking away all the oxygen to the trees which is causing them to die.
5. What is unique about what is happening in the Long Valley Caldera?
This is unique because it is the levels of CO2 aren?t usually this high. The process that is going on also has to take place near a volcano
6. How could what is happening be dangerous to people?
Inhaling high concentrates of carbon dioxide gas can cause dizziness, unconsciousness and death. In the Geological Survey Long Valley Observatory they warn you not to lie face down in the ground anywhere in the Horseshoe Lake.
7. What was the maximum daily emission of CO2 reported per day?
Twenty-one separate area was measured in the area from 1996-1999. The average was 110 metric tons per day.
Topic 3 Cyanobacteria
1. What are cyanobacteria?
Cyanobacteria is a single cell organism that lacks an enclosed nucleus and other cell structures. Cyanobactera is also aquatic and photosynthetic.
2. How long have cyanobacteria existed on earth?
Cyanobacteria has existed for more than 3.5billion years. They also have been known to represent the oldest fossils found on earth. During the earth?s evolution process cyanobacteria was responsible for the formation of much of the pants free breathable oxygen, which allowed the development of oxygen breathing organisms. Stromatolites are actually comprised of living cyanobacteria that grow on top of each other at the rate of 1mm a year.
3. What role did cyanobacteria have in the formation of the atmosphere, as we know it?
The oxygen that we depend on was produced by cyanobateria. It was created during the Archaena and Proterozoic era. Before cyanobacteria the atmosphere was different, and it wasn?t suitable for the present time.
Microsoft Encarta 98, 1993-1997.