Official government site provides comprehensive information on the issue of climate change and global warming including climate change science, U.S. The following article is typical of the information which they provide in addition there are further links contained throughout the article to provide yet more information whether this is for clarification or more detailed reports.
Pollution is 1 Cause
Earth’s temperature is a balancing act
Earth’s temperature depends on the balance between energy entering and leaving the planet’s system . When incoming energy from the sun is absorbed by the Earth system, Earth warms. When the sun’s energy is reflected back into space, Earth avoids warming. When energy is released back into space, Earth cools. Many factors, both natural and human, can cause changes in Earth’s energy balance, including:
Models that account only for the effects of natural processes are not able to explain the warming over the past century. Models that also account for the greenhouse gases emitted by humans are able to explain this warming.
Source: USGRCP (2009)
Changes in the greenhouse effect, which affects the amount of heat retained by Earth’s atmosphere
Changes in the reflectivity of Earth’s atmosphere and surface
These factors have caused Earth’s climate to change many times.
Too Many Cars on Our Roads Cause More Pollution But Modified Cars Like The one above will make our cars more efficient.
Scientists have pieced together a picture of Earth’s climate, dating back hundreds of thousands of years, by analyzing a number of indirect measures of climate such as ice cores, tree rings, glacier lengths, pollen remains, and ocean sediments, and by studying changes in Earth’s orbit around the sun.
The historical record shows that the climate system varies naturally over a wide range of time scales. In general, climate changes prior to the Industrial Revolution in the 1700s can be explained by natural causes, such as changes in solar energy, volcanic eruptions, and natural changes in greenhouse gas (GHG) concentrations.
Recent climate changes, however, cannot be explained by natural causes alone. Research indicates that natural causes are very unlikely to explain most observed warming, especially warming since the mid-20th century. Rather, human activities can very likely explain most of that warming.