The Handy Geography Answer Book. Paul A Tucci
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the world to extend this period past this date. By 2040, many forecast that the production of oil will be 20% of what it is today. Because of technology, like horizontal drilling and fracking, used to extract oil from relatively inaccessible places, we may delay the time when the world runs out of oil.
What are perpetual resources?
Perpetual resources are natural resources, such as solar energy, wind, and tidal energy, that have no chance of being used in excess of their availability. They can be used for power generation and conversion to electric energy indefinitely.
What are fossil fuels?
Underground fuels such as natural gas, oil, and coal are all known as fossil fuels because they are encased in rocks, just like fossils. It takes millions of years of compression and the building up of dead plants, animals, and organic material to create these fuels.
What is a fossil?
The outline of the remains of a plant or animal embedded in rock is called a fossil. Fossils are formed when a plant or animal dies and becomes covered up by sediments. Over time, the layers compress the remains, which are then embedded into the rock.
What are basins and ranges?
Basins and ranges are sets of valleys and mountains that are spaced close together. Most of Nevada and the western part of Utah are composed of sets of basins and ranges.
What is permafrost?
Permafrost describes ground (including soil, rock, organic material, and ice) that is permanently at or below 32 degrees Fahrenheit (0 degrees Celsius) for a minimum of two consecutive years. Its thickness depends on location but can extend from 9.94 to 4,921 feet (3 meters to 1,500 meters) beneath the surface. Permafrost occurs in higher latitudinal regions, which have cold climates.
Is the permafrost thawing?
Yes, the permafrost is thawing. In places with great areas of permafrost, such as Alaska, the permafrost has warmed to the highest level in 10,000 years. During the last 50 years, the Arctic regions have been warming to record-high temperatures. During this time, Alaska’s average temperature has warmed an average of 3.3 degrees above normal.
Why is permafrost so important?
Aside from the mediating effects on the Earth’s temperature, permafrost provides a cover for the habitat that supports wild flora and fauna, which provide sustenance for the entire ecosystem of the Arctic regions, including the many indigenous people who live there. Permafrost also covers organic rich sediment that contains methane hydrates, which may be released into the air as “greenhouse gases.” As the permafrost thaws, these greenhouse gases are released into the atmosphere and may contribute to global climate change. Permafrost makes up 24% of all land in the Northern Hemisphere.
What are greenhouse gases?
Greenhouse gases are chemical compounds that absorb and emit thermal radiation, are present in our atmosphere, and allow direct sunlight to reach the Earth’s surface. But as the heat bounces back from the Earth to the atmosphere, the gases absorb this energy, and less heat from the surface of the Earth is able to escape back into the atmosphere and is trapped in the lower atmosphere. Many greenhouse gases are found in nature, like carbon dioxide, water vapor, methane, nitrous oxide, and ozone, and are regulated by a process called the carbon cycle. The trouble is that man-made greenhouse gases from chlorofluorocarbons (CFCs), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and carbon dioxide created by man-made activities such as the burning of forests and the use of fossil fuels (coal, oil, and natural gas) cause these gaseous emissions to unnaturally rise. For example, human activity causes carbon, which exists in nature in a solid form (as coal), to move to a gaseous form, increasing the concentrations of these gases in our atmosphere.
Evidence is piling up that greenhouse gases from human industry are contributing to global warming of the planet.
When did man-made greenhouse gases begin to be an issue for mankind?
Scientists believe that man-made greenhouse gases began when people began to burn coal at the beginning of the Industrial Revolution in 1750. Measurements of carbon dioxide occurring in our atmosphere in the present day, compared to 1750, show a 40% increase. Experts believe this is a major contributor to the effects of a phenomenon called global warming. The effects of the sudden warming impacts many aspects of our global ecosystem, including our marine ecology, the lives of billions of people, the air that we breathe, and the increase in surface temperatures felt throughout the world.
What percentage of animal species have become extinct over the last 40 years?
According to a 2014 report issued by experts at the World Wildlife Fund, 52% of all animal species on our planet have become extinct in the past 40 years, due to the degradation of our environment.
What is the cryosphere?
The cryosphere is the area of the Earth where water has solidified and includes ice, floating ice, glaciers, permafrost, and snow.
How much of the Earth’s surface is frozen?
About one-fifth of the planet is permafrost, or frozen for all or most of the year.
What do deserts and polar regions have in common?
Deserts and polar regions both have average rainfall of less than four inches (10 cm) per year. Both regions contain some of the driest places on Earth.
What is a jungle?
A jungle is a forest that is composed of very dense vegetation. The term tropical rain forest can often be used interchangeably with jungle. Jungles occur most often in tropical areas such as the Amazon and Congo river basins.
What is a rain forest?
A rain forest is any densely vegetated area that receives over 40 inches (100 centimeters) of rain a year.
What is a tropical rain forest?
A tropical rain forest is a rain forest that lies between the Tropic of Cancer in the north (northernmost latitude around the Earth, where the sun appears directly overhead during the Northern Solstice) and the Tropic of Capricorn in the south (the southernmost latitude around the Earth, where the sun appears directly overhead during the Southern Solstice) or within the “tropics.” Tropical rain forests are known for their very diverse species of plant and animal life. Tropical rain forests exist throughout Central America, northern Brazil, the Congo River Basin, and Indonesia.
Where is the northernmost rain forest?
Juneau, the capital of Alaska, is in the middle of one of the largest and most northerly rain forests in the world, which is located within the Chugach National Forest and Chugach State Park. Other rain forests extend to the northern regions of Japan and Siberia, Russia.
What is a desert?
A desert is an area of light rainfall. Deserts usually have little plant or animal life due to the dry conditions. Contrary to the popular image, deserts are not just warm, sand-swept areas like the Sahara Desert; they can also be frigid areas like Antarctica, one of the driest places on Earth.
How can an area be lower than sea level?
Land in the midst of a continent can be lower than sea level because the land is not close enough to the sea to be flooded with water. Movement of the tectonic plates pushes areas like the Dead Sea in Israel and Death Valley in California to elevations lower than sea level.
What was the highest temperature ever recorded?
World temperature records have been sources of controversy for many years, with many temperature records decertified by such groups as the World Meteorological Organization. For example, the world’s highest temperature, thought to have been recorded in error in the desert in Libya in 1922 as 136 degrees