Climate Change
Climate Change is the long term shift in the expected or average weather. Once, all climate changes occurred naturally, part of the earth's natural interactions between the atmosphere, ocean, land and changes in the amount of solar radiation reaching the earth. However, during the Industrial Revolution, we began altering our climate and environment through new industrial and agricultural practices.
The Industrial Revolution started more than 200 years ago when people began using machines to make life easier. Before this time, human activity released very few pollutants into the atmosphere, but now through population growth, fossil fuel burning and deforestation, we are affecting the atmosphere like never before.
Since the Industrial Revolution, the need for energy to run machines has steadily increased. Most of the energy used to light and heat our homes, as well as the energy needed to make cars run comes from fossil fuels like coal and oil. Burning these fuels releases greenhouse gases.
Understanding the underlying processes of this change will allow us to determine whether this climate change is the result of greenhouse warming or part of longer cycle of natural climate change.
Click on Orbie to Return
to the Global Warming Page
An ice age is a period of reduction in the temperature of the Earth's surface and atmosphere, resulting in an expansion of continental ice sheets, polar ice sheets and alpine ice called glaciers.
The first people arrived in America between 15,000 and 30,000 years ago. During that time, much of North America was covered by glaciers. Some 14,000 years ago, the last ice sheet began to melt. By 7,000 years ago, the ice was gone.
This end to the ice ages caused big changes on the Earth. Many plants and animals that preferred a colder climate were not able to adjust to the warmer, drier conditions and became extinct.
Click on Orbie to find out the fate of the world's iciest regions
Starting in the 14th century and lasting several hundred years, Europeans lived through what is known as the "Little Ice Age". During this time the advance of glaciers along with harsh winters and famines caused some people to starve and others to leave their homes.
Click on Orbie to Return
to the Global Warming Page
The Earth's atmosphere keeps our planet warm by trapping the rays from the sun. The atmosphere is made up of several layers of gases, some of which are greenhouse gases, which act like a blanket keeping in warmth from the sun. This process is known as the Greenhouse Effect and is very important for keeping Earth's temperatures at the right levels for humans, animals and plants to survive.
This natural Greenhouse Effect is absolutely vital to allowing life, as we know it to survive on Earth. Without this, Earth would be 60°F cooler than it is today. The Greenhouse Effect insulates earth, resulting in the mild temperatures, 59.5°F on average, on the surface.
.........
............Click on Orbie to explore an Interactive Model of the Greenhouse Effect
The problem we are facing today is that we have been releasing too many greenhouse gases into the atmosphere. As a result, heat is trapped below the atmosphere and Global Warming is occurring influencing our climate.
Click on Orbie to Return
to the Global Warming Page
Global Warming refers to an average increase in the Earth's temperature, which
in turn causes changes in climate.A warmer Earth may lead to changes in rainfall
patterns, a rise in sea level, and a wide range of impacts on plants, wildlife,and humans. When scientists talk about the issue of climate change, their concern is about Global Warming caused by human activities.
The Earth has warmed about 1°F in the last 100 years. And the four warmest years of the 20th century all happened in the 1990s. Many of the world's leading climatologists think that greenhouse gases are the main reason the Earth is warming.
Click on Orbie to Return
to the Global Warming Page
Carbon Dioxide is the main greenhouse gas which can be made by deforestation and the burning of trees. Your car and other vehicles also add carbon dioxide into the atmosphere,
as does the burning of coal, petrol and other fossil fuels.
Whenever you watch TV, use the air conditioner, turn on a light, or ride in a car you are
sending greenhouse gas into the air
To perform many of these functions, you need to use electricity. Electricity comes from power plants, most of which use coal
and oil to make electricity. Burning coal and oil produces greenhouse gases.
Click on Orbie to Return
to the Global Warming Page
..................Fossil Fuels
One of the main sources of atmospheric carbon dioxide from humans is from the burning of fossil fuels including coal, oil, and natural gas. Temperatures worldwide have shown an upward trend over the past 200 years, with several of the warmest years on record having occurred within the last two decades.
Fossil fuels currently provide more than 85% of all energy consumed in the United States, nearly two-thirds of our electricity, and virtually all of our transportation fuels.
Click on Orbie to Return
to the Global Warming Page
Deforestation refers to the mass removal of trees. When trees are cut down, photosynthesis is reduced, and more carbon dioxide remains in the atmosphere.
Deforestation contributes to carbon dioxide levels in two ways. First, burning or decomposing trees release carbon dioxide into the air. Second, deforestation decreases the number of trees available to remove carbon dioxide from the air. Many scientists agree that the increase in carbon dioxide is contributing to global warming.
............ 
The value of trees as lumber and as firewood and the value of the land they occupy for housing or farming, tend to be short term and specific. In fact, these benefits may be a matter of survival in some regions.
The value of forests for preventing global climate change and preserving the earth's biodiversity, by contrast, are long term and their rewards apply to everyone.
A way has to be found to make the expansion and nurturing of forests appealing and cost-effective to the local populations that usually decide their fate.
Click on Orbie to Return
to the Global Warming Page