What is the relationship between the energy we use today and climate?

Answer

The relationship between the energy we use today and Earth’s climate depends on the source of the energy. People use energy for heating, for transportation, for lighting, for manufacturing, for communication, and for growing and harvesting food.

By far the most common way to produce that energy today is to burn fossil fuels like coal, oil, and natural gas (they’re called fossil fuels because they come from the decomposed remains of ancient life, mostly plants). Fossil fuels account for the vast majority of global energy use. Burning (or, to use a more scientific term, oxidation) releases energy. It also releases waste gases into the atmosphere. That is why we have chimneys and tailpipes — because if these gases could not escape they would choke off the combustion (to say nothing of choking us).

Among those waste gases is carbon dioxide, or CO2. It is a greenhouse gas, meaning it traps heat rather than letting the heat escape into outer space. Before the Industrial Revolution, the human race was not burning enough of anything to make much of a difference. Since then, we have learned to use coal, oil, and natural gas and weh ave been using a lot more machinery. That requires a lot more energy, which means a lot more CO2 in the atmosphere — there is already about 30 percent more of it now than there was before the Revolution, and the level is still rising. (A nearly sevenfold increase in world population since 1800 has also made a big difference).

The additional CO2 that has accumulated in the atmosphere means that more heat is being trapped, which many thousands of scientists agree has already begun to affect the climate and will affect the climate even more as time goes on.

So that is the relationship between energy as we now produce it and climate. It is also why people are talking so much about alternative kinds of energy that don’t add to the greenhouse gases in the atmosphere. Wind turbines, solar energy arrays, nuclear power plants, and geothermal systems, are just a few examples. And coal plants that capture and store CO2 before it escapes into the atmosphere may become a way to use some fossil fuel without changing the climate.

Such “low-carbon” energy will probably cost more than fossil fuel energy costs today. But some prominent economists have pointed that by using such low-carbon energy we could avoid much higher costs that are likely to be caused by global warming.