[B-PT04] 地球生命史

[BPT04-05] 汚染、森林崩壊、温暖化による動物危機が21世紀後半に来る：核戦争で悪化

*海保 邦夫¹ (1.東北大学)

キーワード：汚染、森林崩壊、地球温暖化、核戦争、大量絶滅、人新世

An environmental–animal crisis is currently ongoing and is becoming increasingly severe due to human activity. However, the magnitude, timing, and processes related to this crisis are unclear. This paper clarifies the likely magnitude and timing of animal extinctions and changes as functions of the contributing causes (global warming, pollution, deforestation, and two hypothetical nuclear conflicts) during 2000–2300 CE. This paper demonstrates that an animal crisis marked by a 5–13% terrestrial tetrapod species loss and 2–6% marine animal species loss will occur in the next generation during 2060–2080 CE if humans do not engage in nuclear wars. These variations are due to pollution, deforestation, and global warming. The main causes of this crisis will change from pollution and deforestation to deforestation in 2030 under the low CO₂ emission scenarios but will change from pollution and deforestation to deforestation in 2070 and then to deforestation and global warming after 2090 under the medium CO₂ emissions. A nuclear conflict will increase animal species loss up to a ~60% terrestrial tetrapod species loss and ~40% marine animal species loss. Therefore, preventing nuclear war, reducing deforestation rates, decreasing pollution, and limiting global warming are key tasks for humans.