Estimating surface CO2 fluxes from space-borne CO2 dry air mole fraction observations using an ensemble Kalman Filter
Estimating surface CO2 fluxes from space-borne CO2 dry air mole fraction observations using an ensemble Kalman Filter
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DOI：
10.5194/acp-9-2619-2009
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发表时间：
2009-01-01
影响因子：
6.3
通讯作者：
Dance, S.
中科院分区：
文献类型：
--
作者：
Feng, L.;Palmer, P. I.;Dance, S.
我们已经开发了一个集合卡尔曼滤波器（EnKF）估计8天的区域表面通量的CO2星载CO2干空气摩尔分数观测（X-CO2）和评估的方法，使用一系列的合成实验，准备从美国宇航局轨道碳观测站（OCO）的数据。OCO的工作周期为32天，每16天在短波红外波长的后向散射太阳辐射的最低点和闪烁测量之间交替。EnKF使用的合奏状态表示误差协方差估计8天的CO2地表通量超过144个地理区域。我们使用12 × 8天的滞后窗口，认识到X-CO2测量包括来自先前时间窗口的表面通量信息。将地面CO2通量与大气X-CO2分布联系起来的观测算子包括：a）将地面通量与全球CO2浓度三维分布联系起来的GEOS-Chem传输模型，该模型在无云和具有气溶胶光学厚度的OCO测量的时间和位置采样
We have developed an ensemble Kalman Filter (EnKF) to estimate 8-day regional surface fluxes of CO2 from space-borne CO2 dry-air mole fraction observations (X-CO2) and evaluate the approach using a series of synthetic experiments, in preparation for data from the NASA Orbiting Carbon Observatory (OCO). The 32-day duty cycle of OCO alternates every 16 days between nadir and glint measurements of backscattered solar radiation at short-wave infrared wavelengths. The EnKF uses an ensemble of states to represent the error covariances to estimate 8-day CO2 surface fluxes over 144 geographical regions. We use a 12 x 8-day lag window, recognising that X-CO2 measurements include surface flux information from prior time windows. The observation operator that relates surface CO2 fluxes to atmospheric distributions of X-CO2 includes: a) the GEOS-Chem transport model that relates surface fluxes to global 3-D distributions of CO2 concentrations, which are sampled at the time and location of OCO measurements that are cloud-free and have aerosol optical depths