How have carbon dioxide levels changed in our atmosphere over the last 150 years? (List at least 3 changes)
Carbon dioxide levels have significantly increased in the Earth's atmosphere over the last 150 years due to human activities like the burning of fossil fuels, deforestation and industrial processes. Here are three notable changes in carbon dioxide levels:
1. Steady increase: Since the Industrial Revolution in the mid-1800s, CO2 levels have risen steadily from around 280 parts per million (ppm) to over 400 ppm today. This increase is primarily due to human activities.
2. Seasonal variations: The concentration of CO2 in the atmosphere fluctuates seasonally, increasing during the winter months and decreasing during the summer months. This cycle is due in part to the respiration of plants and trees and the corresponding uptake of CO2 during the growing season.
3. Rate of increase: The rate of CO2 increase in the atmosphere has been accelerating over the last few decades. In the 1960s, the concentration of CO2 in the atmosphere was increasing at a rate of roughly 0.8 ppm per year. By the 2010s, the rate of increase had almost doubled to around 1.5 ppm per year.