对"最近全球CO2受精对植物光合作用的影响下降"的评论
Christian Frankenberg1,2, Yi Yin1, Brendan Byrne2
1Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA.
Science (New York, N.Y.)
|September 23, 2021
概括
卫星数据偏差挑战了二氧化碳受精效应的发现. 研究人员警告不要使用高级非常高分辨率放射仪数据来测量植被趋势,因为这会影响气候变化研究.
科学领域:
- 地球系统科学
- 遥感技术
- 气候变化研究
背景情况:
- 增加大气二氧化碳增强植物生长的二氧化碳施肥效应是气候变化模型中的关键因素.
- 长期卫星记录越来越多地用于估计全球植被反应和光合作用代理.
- 根据卫星数据分析,之前的研究表明,二氧化碳受精效应显著下降.
研究的目的:
- 重新评估报告中的二氧化碳受精效应的强度.
- 确定从卫星记录中影响植被趋势的潜在数据文物.
- 提供关于可靠使用卫星衍生植被指数的指导.
主要方法:
- 对长期卫星数据的分析,特别关注高级非常高分辨率射线仪 (AVHRR) 的记录.
- 调查与植被反射率相关的AVHRR数据中的系统偏差.
- 确定偏差对衍生光合作用代理和植被指数的影响的评估.
主要成果:
- 在高级非常高分辨率放射仪 (AVHRR) 数据中检测到小的系统偏差.
- 这些偏差显著影响了植被趋势的分析,包括植被近红外反射率 (NIRv).
- 由于这些数据偏差,Wang等人报告的二氧化碳受精效应显著下降的关键发现被确定为不稳定.
结论:
- 对于检测长期植被变化,特别是NIRv和植被指数的趋势,高级非常高分辨率放射仪 (AVHRR) 数据的可靠性是值得怀疑的.
- 在解释依靠AVHRR数据来评估CO2受精效应时,建议谨慎.
- 为了完善卫星数据处理技术或利用替代数据集进行强有力的气候变化影响评估,可能需要进一步的研究.
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