Human Impact on the Environment

Human Activities and Global Warming

• Human activities, such as burning fossil fuels, alter Earth's surface at a faster rate than natural geological processes.
• Release of greenhouse gases, including carbon dioxide and methane, increases atmospheric concentration, leading to rising global temperatures.

Global Temperature Increase

• Global temperatures have risen by approximately 4°F since 2016, exceeding historical temperatures.
• Scientists attribute human activities as a significant contributor to global warming.

Ice Ages

• Ice ages were periods of dramatic climate change in Earth's past, with temperatures 5 to 15 degrees Celsius cooler than today.
• During these periods, huge glaciers extended beyond the ice caps.
• There have been about 40 cooling cycles in the past 2.5 million years, according to evidence from ice cores and ocean floor cores.

Milankovitch's Theory

• Mathematician Milutin Milankovitch discovered a pattern of variations in Earth's tilt and orbit around the sun.
• These variations occur at regular intervals, resulting in periods of unusually cool summers in the Northern Hemisphere every 40,000 to 100,000 years.
• Milankovitch theorized that cool summers led to a build-up of reflective ice and snow, which in turn reflected solar energy, causing the cooling trend to escalate.

Gathering Information about Climate Conditions

• Scientists gather information about climate conditions millions of years ago from ice cores and ocean floor cores.
• These cores provide evidence of past climate conditions, allowing scientists to estimate the timing and intensity of ice ages.

This quiz explores how human activities affect the Earth's surface and contribute to global warming. It covers the release of greenhouse gases and their impact on the atmosphere.