26 Apr 2023 | Press releases

亚洲史上最严重的酷暑四月：科学家们敦促采取行动避免新都库什- 喜马拉雅地区的灾难性影响

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随着高温热浪袭击了孟加拉、中国、印度、缅甸和巴基斯坦，本月亚洲气温记录被刷新。国际山地发展中心（ICIMOD）的科学家们敦促全球政府和企业加快减排速度，发展机构来投入更多的气候资金，以努力加快脚步来帮助该地区适应气候变化。

周一（4 月 17 日）孟加拉首都达卡的气温达到41 摄氏度，印度普拉亚格拉吉达到 45 摄氏度，缅甸葛礼瓦达到 44 摄氏度。中国长沙、福州创当地最早入夏记录，浙江的几个城市也刷新了全省4月最高气温记录。 4 月 23 日，巴基斯坦九个城市的气温达到 40 度以上。

高温造成死亡、学校关闭，人们无法工作——均加剧了该地区现有的脆弱性，尤其是贫困和饥饿。

“在亚洲，人为引起的气候变化是我们所见的高温热浪数量与强度不断增加的主要原因。这些信号表明该地区已经出现气候紧急情况，”ICIMOD 的气候和环境专家迪普希卡沙玛 (Deepshikha Sharma) 说。

ICIMOD 高级经济学家兼粮食系统专家阿毕德·侯赛因 (Abid Hussain) 说：“所有气候模型都表明，南亚地区的热浪峰值的频率和强度上将增加。这会直接影响 20 亿人，即对健康和工作的影响，或间接影响冰川融化、洪水、水文变化、反常降雨及山体滑坡。”

高温热浪来袭之际，联合国世界气候报告显示，南极海冰降至有记录以来的最低水平，欧洲阿尔卑斯山的冰川融化“直接突破了图表下限”。

兴都库什-喜马拉雅地区坐拥世界第三大冰冻水体，其变暖速度是全球平均水平的两倍。温度升高意味着冰川融化速度更快，由此产生的冰川融水更难以预测。随着气温持续上升和冰川萎缩，会导致该地区用水和粮食的安全问题，并增加山洪等灾害的可能性。 “由于机构和社区能力不足，大部分灾害都可能演变成灾难，”侯赛因说。

“在最乐观的情况下，将全球变暖限制在 1.5 ℃内，到2100 年，该地区也将失去三分之一的冰川——这将给山区、生态系统、自然界，以及河流下游四分之一的居民带来巨大风险，” 沙玛说。在过去六十年中，兴都库什-喜马拉雅地区的冰层消融速度一直在加快，甚至海拔 6千米以上的冰面也在变薄。

“现阶段，气温变化的速度比我们担心的要快得多，1.5 摄氏度的警告属实太热了，” 沙玛说。 “当务之急是我们在减排和气候适应融资规模等方面取得快速且重大进展，并在适应灾害和减灾风险的措施方面产生更大的影响，以保护人与生态系统，因为与日俱增的脆弱性并不是当地居民的过错。”

ICIMOD 与 NASA、USAID 和其他合作伙伴合作，通过 服务新都库什-喜马拉雅倡议（SERVIR-HKH initiative）来监测与预测区域干旱和极端天气事件，并与我们八个区域成员国的公共机构共享此 区域干旱监测和展望数据（Regional Drought Monitoring and Outlook data）。

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Planning for climate resilience in Nepal: A training manual for local governments

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The nitrogen and carbon footprints of vegetable production in the subtropical high elevation mountain region

Mountain vegetable production has become a critical source of low heat-resistance vegetables in summer in subtropical regions, but evaluations based on life-cycle assessment (LCA) that are relevant to the environment and economics have not been reported. We conducted a survey to compare the cabbage yield and resource inputs for small-holder farms at a high (HEL, 900–1500 m) and low (LEL, 200–600 m) elevations in a subtropical region in Southwest China. We used LCA to quantify the nitrogen (N) and carbon (C) footprints, and used the yield and environmental impacts gap method to determine the potential to mitigate the environmental impacts of farming at HELs and LELs. The results show that the respective average reactive N (Nr) and greenhouse gas (GHG) emissions for the HEL and LEL were 137.0 kg N ha−1 and 6785 kg CO2-eq ha−1, and 126.7 kg N ha−1 and 6153 kg CO2-eq ha−1, respectively. The N and C footprints for the HEL were 17.3% and 16.2% lower, respectively, than those for the LEL due to the higher yield at the HEL. The average cabbage yield was 26.5% greater at the HEL (53.2 t ha−1) than at the LEL (42.0 t ha−1). The average total N application rate at the HEL was 455 kg N ha−1, which was 6.0% greater than that at the LEL. There was great potential for yield increases and the mitigation of N and C footprints by farmers at both the HEL and LEL. Compared to the average of all surveyed farmers for HEL and LEL, those farmers whose yields and N fertilizer production efficiency were both higher than the average of all surveyed farmers (HH groups) reduced their N and C footprints by 44.7–49.4% and 44.4–51.2%, respectively, with 34.4–52.3% higher yield and 9.2–19.8% lower N application rate. This study indicates that high yield, low environmental cost, and high economic benefit can be achieved by advancing agronomic management based on the best farmers’ practices for vegetable production in a subtropical high-elevation mountain region. © 2020 The Author(s)

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