热带森林是碳净来源, 基于地表获取和损失的测量
Matthew C Hansen1, Peter Potapov2, Alexandra Tyukavina2
1Department of Geographical Sciences, University of Maryland, College Park, MD 20740, USA. mhansen@umd.edu.
Science (New York, N.Y.)
|January 12, 2019
概括
追踪森林碳变化的MODIS卫星数据显示空间模式与更高分辨率的树木覆盖损失数据不一致. 目前使用中等分辨率光学数据的方法可能会夸大监测森林碳动态的能力.
科学领域:
- 环境科学
- 遥感技术
- 森林管理
背景情况:
- 准确监测热带森林的碳变化对于了解全球碳循环至关重要.
- 之前的研究依赖于中等分辨率的卫星数据,如MODIS,进行大规模评估.
- 像Landsat这样的高分辨率数据提供了关于树木覆盖损失的详细信息.
研究的目的:
- 评估来自MODIS的热带森林碳变化估计的准确性.
- 将MODIS数据中的碳损失空间模式与Landsat的树木覆盖损失数据进行比较.
- 评估用于森林碳监测的被动中等分辨率光学数据的可靠性.
主要方法:
- 对热带森林碳变化的MODIS (中等分辨率成像光谱仪) 数据的分析.
- 将MODIS空间图案与来自高分辨率Landsat图像的树木覆盖损失数据进行比较.
- 在MODIS衍生碳变化图中评估潜在的委托和遗漏错误.
主要成果:
- 从MODIS数据中得出的森林碳损失的空间模式与Landsat的树木覆盖损失模式不一致.
- 这项研究发现了显著的差异,质疑MODIS衍生碳变化图的准确性.
- 有证据表明,MODIS衍生地图并非没有错误.
结论:
- 使用MODIS等被动中等分辨率光学数据监测森林碳变化的现有能力被夸大了.
- 为了准确评估森林碳动态,需要更高分辨率的数据.
- 需要进一步的研究来改善可靠的森林碳监测方法.
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