论文标题：Amazonian Biomass Burning Enhances Tropical Andean Glaciers Melting

期刊：Scientific Reports

作者：Newton de Magalhães Neto, Heitor Evangelista et.al

发表时间：2019/11/28

数字识别码：10.1038/s41598-019-53284-1

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根据《科学报告》发表的一项研究Amazonian Biomass Burning Enhances Tropical Andean Glaciers Melting，亚马孙流域西南部（巴西、秘鲁和玻利维亚）的雨林火灾可能会加剧安第斯山脉的热带冰川融化。

烟羽从亚马孙流域扩散到安第斯山脉中部

图片来源：Neto等

巴西里约热内卢州立大学的Newton de Magalhães Neto及同事利用2000年至2016年间收集的火灾事件、烟羽流动、降水和冰川融化数据建模，评估亚马孙流域的生物体燃烧对玻利维亚Zongo冰川可能造成的影响。他们发现生物体燃烧产生的气溶胶（比如炭黑）可以随风扩散到安第斯山脉热带冰川，沉降在雪中；由于被炭黑或粉尘覆盖的积雪反射的光减少（返照率下降），冰川融化可能因此加剧。

作者重点分析了2007年至2010年的情况，当时亚马孙流域的火灾季最为严峻。他们调查了炭黑单独作用下和炭黑与先前报道的粉尘综合作用下的积雪返照率，模型显示单独的炭黑或粉尘可能使年冰川融化率增加3-4%；二者共同作用则可能使之增加6%。如果粉尘浓度够高，粉尘单独可能使年冰川融化率增加11-13%，而在存在炭黑的情况下则可达到12-14%。这项发现表明亚马孙流域生物体燃烧的影响取决于积雪中的粉尘浓度。

国际粮食需求相关压力可能导致亚马孙流域的农耕和森林砍伐进一步扩张，由此增加的炭黑和二氧化碳排放可能影响到安第斯山脉冰川。

摘要：The melting of tropical glaciers provides water resources to millions of people, involving social, ecological and economic demands. At present, these water reservoirs are threatened by the accelerating rates of mass loss associated with modern climate changes related to greenhouse gas emissions and ultimately land use/cover change. Until now, the effects of land use/cover change on the tropical Andean glaciers of South America through biomass burning activities have not been investigated. In this study, we quantitatively examine the hypothesis that regional land use/cover change is a contributor to the observed glacier mass loss, taking into account the role of Amazonian biomass burning. We demonstrated here, for the first time, that for tropical Andean glaciers, a massive contribution of black carbon emitted from biomass burning in the Amazon Basin does exist. This is favorable due to its positioning with respect to Amazon Basin fire hot spots and the predominant wind direction during the transition from the dry to wet seasons (Aug-Sep-Oct), when most fire events occur. We investigated changes in Bolivian Zongo Glacier albedo due to impurities on snow, including black carbon surface deposition and its potential for increasing annual glacier melting. We showed that the magnitude of the impact of Amazonian biomass burning depends on the dust content in snow. When high concentration of dust is present (e.g. 100 ppm of dust), the dust absorbs most of the radiation that otherwise would be absorbed by the BC. Our estimations point to a melting factor of 3.3 ± 0.8% for black carbon, and 5.0 ± 1.0% for black carbon in the presence of low dust content (e.g. 10 ppm of dust). For the 2010 hydrological year, we reported an increase in runoff corresponding to 4.5% of the annual discharge during the seasonal peak fire season, which is consistent with our predictions.

（来源：科学网）