Fossil Fuels

Fossil Fuels

There are mighty weather systems on the Earth – and in the high atmosphere of Venus and on Jupiter. There are sandstorms on the Earth and on Mars, lightning on Jupiter and Venus and Earth. Volcanoes inject debris into the atmospheres of the Earth and Io. Internal geological processes slowly deform the surfaces of Venus, Mars, Ganymede and Europe, as well as Earth. Glaciers, proverbial for their slowness, produce major reworkings of landscapes on the Earth and probably also on Mars. These processes need not be constant in time. Most of Europe was once covered with ice. A few millions years ago, the present site of the city of Chicago was buried under three kilometers of frost. On Mars and elsewhere in the Solar system, we see features that could not be produced today, landscapes carved hundreds of millions or billions of years ago when the planetary climate was probably very different.

There is an additional factor that can alter the landscape and the climate of Earth: intelligent life, able to make major environmental changes. Like Venus, the Earth also has a greenhouse effect due to its carbon dioxide and water vapor. The global temperature would be below the freezing point of water.

There is an additional factor that can alter the landscape and the climate of Earth: intelligent life. Image: © Elena

The principal energy sources of our present industrial civilization are the so-called fossil fuels. We burn wood and oil, coal and natural gas, and, in the process, release waste gases, principally CO2, into the air. Consequently, the carbon dioxide content of the Earth ‘s atmosphere is increasing dramatically. The possibility of a runaway greenhouse effect suggests that we have to be careful: Even a one- or two- degree rise in the global temperature can have catastrophic consequences. In the burning of coal and oil and gasoline, we are also putting acid into the atmosphere. Like Venus, our stratosphere even now has a substantial mist of tiny sulfuric acid droplets. Our major cities are polluted with noxious molecules. We do not understand the long-term effects of our course of action.

But we have also been perturbing the climate in the opposite sense. For hundreds of thousands of years human beings have been burning and cutting down forests and encouraging domestic animals to graze on and destroy grasslands. Slash-and-burn agriculture, industrial tropical deforestation and overgrazing are rampant today. But forests are darker than grasslands, and grasslands are darker than deserts. As a consequence, the amount of sunlight that is absorbed by the ground has been declining, and by changes in the land use are lowering the surface temperature of our planet.