Scientists Study Melting Permafrost
The melting of permafrost due to rising global temperatures is a significant environmental concern, particularly because of its impact on methane release. Permafrost, which is frozen soil that has remained below 0°C for at least two consecutive years, stores vast amounts of organic carbon. As it thaws, microbes break down the organic material, releasing methane (CH₄), a potent greenhouse gas. Dr. Katey Walter Anthony, a leading researcher on Arctic permafrost, warns, "Methane emissions from thawing permafrost could create a feedback loop that accelerates global warming." This means that as temperatures rise, more permafrost melts, releasing more methane, which further intensifies climate change. Research published in Nature Climate Change suggests that permafrost thaw could contribute an additional 150 billion tons of carbon emissions by 2100, significantly impacting climate targets. Moreover, NASA scientist Charles Miller has stated, "We are already detecting increases in methane emissions from permafrost regions, and this trend is expected to continue." These emissions are particularly concerning because methane is about 25 times more effective at trapping heat in the atmosphere than carbon dioxide over a 100-year period. If left unchecked, permafrost thaw could dramatically amplify global warming, making mitigation efforts even more urgent.
Which of the following best explains the author’s reasoning about the impact of melting permafrost?