Planets have some heat.
The Earth and other planets retain some residual heat left from the time planets and the Sun were formed four or five billion years ago. In addition, there are some internal sources of heat such as radioactive decay. Earth and other planets also gain heat from the Sun.
Planets lose heat.
Overwhelmingly, the mechanism for heat loss is through radiation of heat. All objects radiate heat in the form of electromagnetic radiation. (One can look up "black body radiation" which is an interesting topic in its own.) For Earth, this is typically characterized as infra-red radiation. The radiation is emitted from the Earth, through the atmosphere and heads out into cold space.
(Space, all the apparent emptiness we see in the night sky, is at a temperature of about 4 degrees Celsius above absolute zero, compared to our temperature of almost 300 degrees above absolute zero. The cooling through radiation of the hot Earth is evident in our daily lives because the cooling we experience at night can be so dramatic. In particular, clouds prevent much infrared radiation from directly escaping. A cloudy night cools several degrees less than a clear night.)
There are complications.
Though there is no question that the Earth loses heat by radiating it into space, the details get complex. There are a lot of complications about how much energy of this sort is absorbed by the atmosphere and that leads to discussions of the Greenhouse Effect, but that can be left to another question. The greenhouse effect is quite real and part of the complex balance of energy incoming and energy radiated that can occupy a long discussion.
- Industry burns fossil fuels, particularly coal, emitting sulphur dioxide
- Vehicles from all kinds of transport release nitrogen oxides
- Winds may carry these pollutants in any direction
- Clouds and falling rain absorb these pollutants and the rain falls as a mild acid
- This damages soils, lakes, fish stocks and agriculture as well as corroding metal and damages buildings.
The whole world will be affected in one way or another by global warming. Millions suffered from the extensive, record floods of 2011, which may or may not have been caused or exacerbated by global warming. Although we can not say that any one climatic event must have occurred specifically because of global warming, scientists say that these floods are consistent with their predictions. In other cases, farmers will be affected by more prolonged droughts. Those who live in coastal communities may be affected by rising sea levels, higher storm surges and coastal erosion because of global warming. Millions may be displaced from low-lying areas of Bangladesh, China and some of the Pacific Island nations.
To start with, there are 165,000 wind turbines producing clean, safe, carbon-free electricity world-wide, with hundreds and thousands in most jurisdictions today. Wind energy is on track to have greater generating capacity than nuclear by 2015 or 2016.
At present, wind energy produces 20% of Holland's needs and is becoming a significant contributor in many other jurisdictions world wide, including Ontario and Texas.
Wind is widely used by societies world-wide.
That said, the primary barrier to wider-spread adoption was greater cost per kilowatt hour for wind energy than for other forms of generation such as nuclear, fossil fuel and hydro. The long-standing subsidies and the lack of full-cost-accounting typically made wind appear uneconomic.
With world-wide investment in wind power through various forms of tax credits and guaranteed rate contracts, the wind industry has increased to achieve significant economies of scale which reduced the actual price substantially. Where there is a level playing field either through matching support as with Ontario's Feed-in-Tariff or the USA's current (but threatened) PTC, or where there is no support for any form of generation such as in Brazil, wind is currently very competitive on a pure price basis.
A:One of the reasons wind energy is not used more is that political and other interest groups have lobbied against its use.
Global warming is an observed increase in the average temperature of the Earth's atmosphere and oceans. The average global temperature has increased by around 0.75 degrees Celsius since the start of the Industrial Age. Part of this increase may be due to natural processes, and would have occurred independently of human activity. However, the consensus of most climate scientists is that global warming is substantially the result of human activities. They say that global warming is being caused by an enhanced greenhouse effect, resulting from an increase in atmospheric concentrations of greenhouse gases.
Gases that contribute to global warming include carbon dioxide, methane, nitrous oxides, chlorofluorocarbons (CFCs), and halocarbons (the replacements for CFCs). The carbon dioxide emissions are primarily from the use of fossil fuels for energy and from deforestation.
Global warming is real and is happening to the earth. Governments and individuals around the world are becoming alarmed at the potential harm that can result from global warming, and are taking action to reduce our carbon emissions.