Global Carbon Budget 2022
Global Carbon Budget 2022
复制标题
DOI：
10.5194/essd-14-4811-2022
复制
发表时间：
2022-11-11
影响因子：
11.4
通讯作者：
Zheng, Bo
中科院分区：
文献类型：
--
作者：
Friedlingstein, Pierre;O'Sullivan, Michael;Zheng, Bo
准确评估人为二氧化碳（CO2）排放及其在气候变化中在大气、海洋和陆地生物圈中的重新分布，对于更好地理解全球碳循环、支持气候政策的制定和预测未来气候变化至关重要。在这里，我们描述和综合数据集和方法来量化全球碳预算的五个主要组成部分及其不确定性。化石CO2排放量（E-FOS）依据的是能源统计和水泥生产数据，而土地使用变化（E-LUC）排放量（主要是毁林）依据的是土地使用和土地使用变化数据以及簿记模型。大气CO2浓度直接测量，其增长率（G（ATM））是根据浓度的年变化计算的。海洋CO2汇（S-OCEAN）是用全球海洋地球化学模式和基于观测的数据产品估算的。用动态全球植被模型估算了陆地CO2汇（S-LAND）。由此产生的碳收支不平衡（B-IM），即估计的总排放量与估计的大气、海洋和陆地生物圈变化之间的差异，是对当代碳循环不完善数据和理解的一种衡量。所有不确定性报告为+/- 1 sigma。2021年，EFOS相对于2020年增加了5.1%，化石排放量为10.1 +/- 0.5 GtC yr（-1）（包括水泥碳酸化汇时为9.9 +/- 0.5 GtC yr（-1）），ELUC为1.1 +/- 0.7 GtC yr（-1），人为CO2排放总量（包括水泥碳酸化汇）为10.9 +/- 0.8 GtC yr 1（40.0 +/- 2.9 GtCO（2））。此外，2021年，G（ATM）为5.2 +/- 0.2 GtC yr（-1）（2.5 +/- 0.1 ppm yr（-1）），S-海洋为2.9 +/- 0.4 GtC yr（-1），SLAND为3.5 +/- 0.9 GtC yr（-1），B-IM为0.6 GtC yr（-1）（即估算的源总量过低或汇总量过高）。2021年全球大气CO2浓度平均值达到414.71 +/- 0.1 ppm。2022年的初步数据表明，全球E-FOS相对于2021年增加了+1.0%（0.1%至1.9%），大气CO2浓度达到417.2 ppm，比工业化前水平（约278 ppm）高出50%以上。总体而言，在1959-2021年期间，全球碳收支各组成部分的平均值和趋势是一致估计的，但在CO2通量的年度至半年度变化的代表性方面，持续存在高达1 GtC yr（-1）的差异。对多种方法和观测的估计值进行比较表明：（1）土地利用变化排放量估计值持续存在很大的不确定性;（2）不同方法对北方热带外地区陆地CO2通量大小的一致性很低;（3）不同方法对过去十年海洋汇强度的估计值存在差异。本次更新的动态数据记录了新的全球碳预算中使用的方法和数据集的变化，以及与以前发布的数据集相比，对全球碳循环的理解取得的进展。本工作中提供的数据可在https://doi.org/10.18160/GCP-2022获得（Friedlingstein等人，2022 b）。
Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere in a changing climate is critical to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe and synthesize data sets and methodologies to quantify the five major components of the global carbon budget and their uncertainties. Fossil CO2 emissions (E-FOS) are based on energy statistics and cement production data, while emissions from land-use change (E-LUC), mainly deforestation, are based on land use and land-use change data and bookkeeping models. Atmospheric CO2 concentration is measured directly, and its growth rate (G(ATM)) is computed from the annual changes in concentration. The ocean CO2 sink (S-OCEAN) is estimated with global ocean biogeochemistry models and observation-based data products. The terrestrial CO2 sink (S-LAND) is estimated with dynamic global vegetation models. The resulting carbon budget imbalance (B-IM), the difference between the estimated total emissions and the estimated changes in the atmosphere, ocean, and terrestrial biosphere, is a measure of imperfect data and understanding of the contemporary carbon cycle. All uncertainties are reported as +/- 1 sigma. For the year 2021, EFOS increased by 5.1% relative to 2020, with fossil emissions at 10.1 +/- 0.5 GtC yr(-1) (9.9 +/- 0.5 GtC yr(-1) when the cement carbonation sink is included), and ELUC was 1.1 +/- 0.7 GtC yr(-1),for a total anthropogenic CO2 emission (including the cement carbonation sink) of 10.9 +/- 0.8 GtC yr 1 (40.0 +/- 2.9 GtCO(2)). Also, for 2021, G(ATM) was 5.2 +/- 0.2 GtC yr(-1) (2.5 +/- 0.1 ppm yr(-1)), S-OCEAN was 2.9 +/- 0.4 GtC yr(-1), and SLAND was 3.5 +/- 0.9 GtC yr(-1), with a B-IM of 0.6 GtC yr(-1) (i.e. the total estimated sources were too low or sinks were too high). The global atmospheric CO2 concentration averaged over 2021 reached 414.71 +/- 0.1 ppm. Preliminary data for 2022 suggest an increase in E-FOS relative to 2021 of +1.0% (0.1% to 1.9 %) globally and atmospheric CO2 concentration reaching 417.2 ppm, more than 50% above pre-industrial levels (around 278 ppm). Overall, the mean and trend in the components of the global carbon budget are consistently estimated over the period 1959-2021, but discrepancies of up to 1 GtC yr(-1) persist for the representation of annual to semi-decadal variability in CO2 fluxes. Comparison of estimates from multiple approaches and observations shows (1) a persistent large uncertainty in the estimate of land-use change emissions, (2) a low agreement between the different methods on the magnitude of the land CO2 flux in the northern extratropics, and (3) a discrepancy between the different methods on the strength of the ocean sink over the last decade. This living data update documents changes in the methods and data sets used in this new global carbon budget and the progress in understanding of the global carbon cycle compared with previous publications of this data set. The data presented in this work are available at https://doi.org/10.18160/GCP-2022 (Friedlingstein et al., 2022b).