The greenhouse effect is important. It blankets the Earth and keeps it warm enough to support life. Without it, Earth would be a lifeless planet; however, too much of it could be disastrous!
Humans are a geological force able to reshape our environment. Just as a volcano, earthquake or ocean current shapes the land and climate, so do our actions. The release of greenhouse gasses (carbon dioxide, methane and nitrous oxide) as a result of human activities is changing the amount of radiation coming in and leaving Earth’s atmosphere. The concentrations of greenhouse gasses in the atmosphere have historically varied as a result of natural processes such as volcanic activity. Yet, since the Industrial Revolution humans have added significant amounts of these greenhouse gasses to the atmosphere by burning fossil fuels, cutting down forests, raising livestock, mining coal, putting garbage in landfills, disposing human and animal waste in treatment plants and many other activities. This change in radiation is contributing to changes in climate.
Because of the human influence on the planet, there are changes in how Earth’s systems work. A change in one system influences all others. This is evident in the Bering Sea…the most productive ocean in the world. Food chains are altered as the average ocean temperature rises. This Polar-Palooza video describes it well. As food chains are altered, so are cultures. In this Polar-Palooza video, Perry Pungowiyi describes how the Siberian Yupik are wholly dependent on ice and communicates his distress with regard to the melting ice and demise of his culture.
Module VII provides one with an understanding of Earth’s cycles and how humans are disrupting them. A healthy understanding of these cycles is critical in order to ensure the health and safety of future generations of living things on Earth.
Image taken from apps1.eere.energy.gov
