Causes of Climate Change
There have been many suspected causes of climate change which have been discovered by various scientific methods. I will cover this and more in the paragraphs that follow.
Climate change has been occurring since the formation of the earth, 4.6 billion years ago. There are a host of natural causes of climate change, from astronomy and the sun to continental drift, volcanism and, more recently, the activities of mankind follow the links below for more info). However the latest changes are alarming in the speed at which they are occurring. More on that later...
What is "Climate" Anyway?
Before going further with "causes of climate change" would like to answer the question - what is climate? Climate is the "average" weather to be expected at a certain location. Average weather changes daily with a natural variability - the seasons change, there are air mass changes usually every few days when frontal systems pass through an area, there are sunny days and stormy days. There are dry periods and wet periods. Climate is the term used to describe what the typical weather is to be expected at a certain location for a given date.
Currently - with the knowledge that climate is changing - it is accepted practice to calculate 30-year normals of temperature and precipitation, along with other variables. These averages are updated every decade and more closely describe the general changes in climate. The 30-year normals have been increasing lately.
There are many theories for these changes implicated by scientists. Some of them have been around since the beginning of time and are considered natural causes. Some of these natural causes are ethereal in nature - such as astronomical forcing and changes in solar radiation. Some of the changes deal with volcanoes, and even others seem to be other cycles that escape understanding or are poorly understood.
There has been growing evidence of climate change caused by man, due in large part to the consumption of fossil fuels for energy. This had lead to what scientists are calling "global warming".
Some of the newest research being conducted in the attempt to better grasp causes of climate change is to try to better understand the function of clouds in climate modeling. Global climate models are used heavily in predicting how the world's climate will change when greenhouse gases increase. However there is uncertainty with cloud cover as one of the causes of climate change.
As mankind continues to influence the climate there will be a time when these artificial forcings overwhelm the natural astromical forcings, that have been dominant since the beginning of the earth's existence. Moreover, even though we will be "due" for the next ice age in a few thousand years, the warming may delay the onset of glaciation indefinitely. Not all scientists buy into this theory. But there are a few, like James Hansen, who believes we will prevent the next ice age but simply overwheling natural trigger mechanisms for the next cooliong episode. Not to get off track - more will be covered about this at a later time. :)