長文読解（人文系・自然科学系の文章）- 問題3

The Arctic's permafrost regions are experiencing rapid transformation due to global warming, creating a potentially dangerous feedback loop in the Earth's climate system. As temperatures rise, these frozen soils are thawing, releasing massive amounts of carbon dioxide and methane that have been trapped for thousands of years. Scientists estimate that permafrost contains approximately twice the amount of carbon currently present in the Earth's atmosphere.
This thawing process is particularly concerning because it accelerates climate change in a process known as the "carbon bomb" effect. As organic matter hidden in the frozen ground decomposes, it releases greenhouse gases that further increase global temperatures. Satellite imagery and ground-based research show that some Arctic regions are warming at nearly three times the global average rate, causing significant changes in landscape and biodiversity.
Researchers are now racing to understand the full implications of this phenomenon. Some ecosystems are adapting by shifting vegetation patterns, while others are experiencing dramatic disruptions. The potential release of ancient microbes and the transformation of Arctic landscapes pose unprecedented challenges for global environmental management and climate prediction models.