What is the significance of climate change thresholds in the Earth's climate system? a. They show the maximum greenhouse gas levels that the atmosphere can safely absorb without consequences. b. They represent critical tipping points that, once

The significance of climate change thresholds in the Earth's climate system is best described by: **b. They represent critical tipping points that, once crossed, can cause irreversible environmental changes.** These thresholds indicate levels or conditions within the climate system where a small change can lead to significant and often irreversible impacts on the environment, ecosystems, and climate patterns.