Final answer:
The Mauna Loa CO₂ data show a steady increase in CO₂ levels, now at about 2.6 ppm per year, superimposed with seasonal variations due to photosynthesis. Ice core evidence complements these findings, revealing natural historical climate cycles, but the current rapid CO₂ rise is unmatched in speed and scale.
Step-by-step explanation:
The data from Mauna Loa CO₂ measurements reveal an overall upward trend in atmospheric CO₂ levels since recordings began in 1958. This trend demonstrates an accelerating increase in CO₂ concentration, with current levels rising about 2.6 parts per million (ppm) per year. Historically, atmospheric CO₂ fluctuated between 180 ppm and 300 ppm, but the industrial activities of modern society have driven levels beyond this range in just hundreds of years. The yearly oscillation observed in the data is attributed to the seasonal cycle of photosynthesis, affecting CO₂ levels as vegetation growth and decay vary with the seasons.
Ice core data, such as those from Antarctic ice cores, provide further evidence of these long-term trends in CO₂ concentrations and temperatures, revealing cycles of climate change over the past 400,000 years. However, the recent rapid rise in CO₂, driven by anthropogenic factors, is unprecedented in the rate and magnitude of change when compared to historical natural cycles.