Risks associated with global warming of 1.5 to 4 °C above pre-industrial levels in human and natural systems in six countries
Risks associated with global warming of 1.5 to 4 °C above pre-industrial levels in human and natural systems in six countries
复制标题
全球变暖比工业化前水平高 1.5 至 4 °C 给六个国家的人类和自然系统带来风险
DOI：
10.1007/s10584-023-03646-6
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发表时间：
2024
期刊：
影响因子：
4.8
通讯作者：
Warren R
中科院分区：
文献类型：
--
作者：
Warren R
专题集《六个脆弱国家的气候变化风险应计》使用一套一致的气候变化和社会经济情景，对六个国家（中国、巴西、埃及、埃塞俄比亚、加纳和印度）由于全球变暖 1.5–4°C 而对人类和自然系统造成的风险进行了统一评估。它比较了2100年升温达到3°C时的风险，大致对应于当前的全球温室气体减排政策，包括各国的国家自主贡献，而不是《巴黎协定》中将升温限制在“远低于”2°C并“努力”限制在1.5°C的目标。假设全球人口要么保持在 2000 年的水平，要么到 2100 年增加到 92 亿。无论哪种情况，预计变暖加剧将导致所有六个国家的土地和人民更容易遭受干旱和洪水灾害，生物多样性进一步下降，玉米和小麦产量进一步减少。与 3°C 相比，将全球变暖限制在 1.5°C 预计将为所有六个国家带来巨大利益，包括减少河流洪水造成的经济损失。最大的预计效益是避免农业用地遭受严重干旱的风险大幅增加，在 1.5°C 时，埃塞俄比亚、中国、加纳和印度的严重干旱程度比 3°C 时低 61%、43%、18% 和 21%，而在这六个国家中，1.5°C 时，人类遭受严重干旱的风险比 3°C 低 20-80%。加纳、中国和埃塞俄比亚的植物气候保护区在升温 1.5°C 时基本得以保留，但如果升温达到 3°C，加纳、中国、印度、埃塞俄比亚和巴西的植物气候保护区面积分别缩小 2、3、3、4 和 10 倍。沿海国家与海平面上升相关的经济损失预计会增加，但如果升温限制在 1.5°C，损失会更加缓慢。实地的实际效益还取决于国家和地方的具体情况以及未来适应投资的程度。
The Topical Collection “Accrual of Climate Change Risk in Six Vulnerable Countries” provides a harmonised assessment of risks to human and natural systems due to global warming of 1.5–4 °C in six countries (China, Brazil, Egypt, Ethiopia, Ghana, and India) using a consistent set of climate change and socioeconomic scenarios. It compares risks in 2100 if warming has reached 3 °C, broadly corresponding to current global greenhouse gas emission reduction policies, including countries’ National Determined Contributions, rather than the Paris Agreement goal of limiting warming to ‘well below’ 2 °C and ‘pursuing efforts’ to limit to 1.5 °C. Global population is assumed either constant at year 2000 levels or to increase to 9.2 billion by 2100. In either case, greater warming is projected to lead, in all six countries, to greater exposure of land and people to drought and fluvial flood hazard, greater declines in biodiversity, and greater reductions in the yield of maize and wheat. Limiting global warming to 1.5 °C, compared with ~ 3 °C, is projected to deliver large benefits for all six countries, including reduced economic damages due to fluvial flooding. The greatest projected benefits are the avoidance of a large increase in exposure of agricultural land to severe drought, which is 61%, 43%, 18%, and 21% lower in Ethiopia, China, Ghana, and India at 1.5 °C than at 3 °C, whilst avoided increases in human exposure to severe drought are 20–80% lower at 1.5 °C than 3 °C across the six countries. Climate refugia for plants are largely preserved at 1.5 °C warming in Ghana, China, and Ethiopia, but refugia shrink in areal extent by a factor of 2, 3, 3, 4, and 10 in Ghana, China, India, Ethiopia, and Brazil, respectively, if warming reaches 3 °C. Economic damages associated with sea-level rise are projected to increase in coastal nations, but more slowly if warming were limited to 1.5 °C. Actual benefits on the ground will also depend on national and local contexts and the extent of future investment in adaptation.