论文标题
是否有证据表明二氧化碳空气中的趋势？
Is there evidence of a trend in the CO2 airborne fraction?
论文作者
论文摘要
在最近在该期刊上发表的论文中，Van Marle等人。 （Van Marle等，2022）引入了一个有趣的新数据集，用于土地使用和土地覆盖变化CO2排放（LULCC），它们用来研究空气载分数（AF）中是否存在趋势，该数据定义为大气中剩余的二氧化碳发射的部分。总体共识没有发现数据趋势的统计证据（Knorr，2009; Gloor et al。，2010; Raupach等，2014; Bennedsen et al。，2019年），研究了AF趋势的假设引起了很多关注。在他们的论文中，Van Marle等人。分析三个不同的LULCC排放时间序列（GCP，H＆N及其新数据系列）所隐含的AF。在基于其新的LULCC排放数据的蒙特卡洛模拟研究中，Van Marle等人。找到AF趋势下降的证据。 在本说明中，我们认为van Marle等人介绍的统计分析。可以在几个方面得到改善。具体而言，在Van Marle等人中提出的蒙特卡洛研究。不利于确定AF是否存在趋势。此外，我们通过使用各种不同的统计检验来重新检查AF趋势的证据。空气传播部分中不间断（正或负）趋势的统计证据充其量仍然混合在一起。当允许趋势中断时，有一些证据表明两个子样本中的上升趋势。
In a paper recently published in this journal, van Marle et al. (van Marle et al., 2022) introduce an interesting new data set for land use and land cover change CO2 emissions (LULCC) that they use to study whether a trend is present in the airborne fraction (AF), defined as the fraction of CO2 emissions remaining in the atmosphere. Testing the hypothesis of a trend in the AF has attracted much attention, with the overall consensus that no statistical evidence is found for a trend in the data (Knorr, 2009; Gloor et al., 2010; Raupach et al., 2014; Bennedsen et al., 2019). In their paper, van Marle et al. analyze the AF as implied by three different LULCC emissions time series (GCP, H&N, and their new data series). In a Monte Carlo simulation study based on their new LULCC emissions data, van Marle et al. find evidence of a declining trend in the AF. In this note, we argue that the statistical analysis presented in van Marle et al. can be improved in several respects. Specifically, the Monte Carlo study presented in van Marle et al. is not conducive to determine whether there is a trend in the AF. Further, we re-examine the evidence for a trend in the AF by using a variety of different statistical tests. The statistical evidence for an uninterrupted (positive or negative) trend in the airborne fraction remains mixed at best. When allowing for a break in the trend, there is some evidence for upward trends in both subsamples.
