Climate change and The Greenhouse Effect

Climate change

The Earth's climate has demonstrated change continuously throughout history. This change is believed to be due to a range of causes including natural changes in solar energy, volcanic eruptions and some anticipated alterations in greenhouse gas (GHG) concentrations. According to NASA (https://climate.nasa.gov/evidence/) in the last 650,000 years there have been seven cycles of glacial advance and retreat, with the abrupt end of the last ice age about 7,000 years ago marking the beginning of the modern climate era — and of human civilization itself. Most of these climate changes are attributed to very small variations in the Earth’s orbit that change the amount of solar energy our planet receives.

However, 97% of climate scientists agree that climate-warming trends over the past century are very likely due to human activities, and most of the leading scientific organizations worldwide have issued public statements endorsing this position.

Since the Industrial Revolution began around 1750, human activities have contributed substantially to climate change by adding carbon dioxide (CO2) and other heat-trapping gases such as methane (CH4) and nitrous oxide (N2O) into the atmosphere. These GHG emissions have helped cause what is known as The Greenhouse Effect and have caused Earth’s surface temperature to rise. The Greenhouse Effect is explained below:

The Greenhouse Effect

When sunlight reaches the Earth’s surface, it can either be reflected back into space or absorbed by Earth. Once absorbed, the planet releases some of the energy back into the atmosphere as heat (also called infrared radiation). Greenhouse gases like water vapour (H2O), carbon dioxide (CO2), and methane (CH4) absorb energy, slowing or preventing the loss of heat to space. In this way, GHG act like a blanket, making Earth warmer than it would otherwise be. This process is commonly known as The Greenhouse Effect. The primary way humans have activated these changes with GHG emissions is by burning fossil fuels for energy consumption.