Regional distribution of large blowdown patches across Amazonia in 2005 caused by a single convective squall line
Regional distribution of large blowdown patches across Amazonia in 2005 caused by a single convective squall line
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2005 年由单一对流飑线引起的亚马逊流域大面积排污斑块的区域分布
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
J. Chambers
中科院分区：
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作者：
Raquel Fernandes Araujo;B. Nelson;C. K. S. Celes;J. Chambers
2005年1月中旬，一条对流性飑线从西南向东北穿越亚马逊河流域4.5 × 106平方公里。正如陆地卫星图像所示，这场非典型的对流风暴留下了弥漫的几何形状，不像更频繁的东向西传播的飑线的扇形风扰动。以前的工作报告了0.2%的森林面积受到这一相对罕见的事件在一个陆地卫星图像，并假设类似的干扰整个导线。2005年，我们通过在30幅Landsat图像中识别大规模（>4公顷）的吹落痕迹，绘制了对流风对该地区的损害影响。与这条单独的飑线相关的扩散型印记占2005年整个地区检测到的风扰动面积的60-72%，但损害高度集中在亚马逊河流域中部。因此，2005年亚马逊河流域大面积风灾斑块的分布与长期平均值有很大不同。对于较小的斑块大小，风力驱动的树木死亡率的区域分布仍然未知。
In mid‐January 2005 a convective squall line traversed 4.5 × 106 km2 of Amazonia from southwest to northeast. As seen in Landsat images, this atypical convective storm left blowdown imprints with diffuse geometry, unlike the fan‐shaped wind disturbance of much more frequent east‐to‐west propagating squall lines. Previous work reported 0.2% of the forest area damaged by this one relatively rare event within one Landsat image and assumed similar disturbance across the entire traverse. We mapped convective wind damage impact to the region in 2005 by identifying large‐scale (>4 ha) blowdown imprints in 30 Landsat images. The diffuse‐type imprints associated with this single squall line contributed up to 60–72% of total 2005 wind‐disturbed area detected across the region, but damage was highly concentrated in central Amazonia. Consequently, the distribution of large wind damage patches in 2005 across Amazonia was very different from long‐term average. Regional distribution of wind‐driven tree mortality for smaller patch sizes remains unknown.