Spatio-Temporal Mapping of Multi-Satellite Observed Column Atmospheric CO2 Using Precision-Weighted Kriging Method
Abstract
:1. Introduction
2. Dataset
2.1. XCO2 from Multi-Satellite Observations
2.2. The Total Carbon Column Observing Network
2.3. XCO2 from Model Simulation
3. Method
3.1. Preprocessing
3.1.1. Adjustment of a Priori Vertical Profiles and Averaging Kernels
3.1.2. Unification of Observing Time and Spatio-Temporal Scales
3.2. Modeling XCO2 Spatio-Temporal Random Field for use in Kriging
3.3. Precision Weighted Spatio-Temporal Kriging
3.3.1. Conventional Spatio-Temporal Kriging
3.3.2. Optimization of Spatio-Temporal Correlation Structure
3.3.3. Integrating XCO2 Using Variable Data Precision
3.3.4. Uncertainty and Precision of Mapped XCO2
3.4. Validation of Global Mapped XCO2
4. Results
4.1. Integrated-XCO2 from Three Satellites
4.2. Globally-Mapped XCO2
4.2.1. Latitudinal and Temporal Variability of Globally Mapped XCO2
4.2.2. Comparison with Conventional Spatio-Temporal Kriging Results
4.2.3. Spatial Distribution of GM-XCO2
4.3. GM-XCO2 Validation
4.3.1. Evaluation Using Cross-Validation
4.3.2. Validation of GM-XCO2 with TCCON Measurements
4.4. Comparison between GM-XCO2 and CarbonTracker Simulated XCO2
4.4.1. Comparison with Latitudinal and Temporal Variability of CT-XCO2
4.4.2. Temporal Variability of GM-XCO2 and CT-XCO2 in Mid-Latitudes
5. Discussion
6. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
Appendix A
Acronyms
Acronyms | Full Names |
XCO2 | Column-averaged dry air mole fraction of atmospheric CO2 |
Original XCO2 retrievals from satellites | |
Adjusted | |
Converted | |
Integrated combination of | |
GM-XCO2 | Global mapped XCO2 |
ENVISAT | Environmental Satellite |
SCIAMACHY | SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY |
GOSAT | Greenhouse Gases Observing Satellite |
OCO-2 | Orbiting Carbon Observatory-2 |
BESD | Bremen Optimal Estimation–DOAS |
ACOS | Atmospheric CO2 Observations from Space |
TCCON | The total carbon column observing network |
CT | CarbonTracker |
r2 | the coefficient of determination |
RMSE | the root mean square error |
ESRL | Earth System Research Laboratory |
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Attributes\Satellites | ENVISAT/SCIAMACHY | GOSAT | OCO-2 |
---|---|---|---|
Period of selected data | January 2003–March 2012 | June 2009–May 2016 | September 2014–December 2016 |
Repeat cycle (days) | 35 | 3 | 16 |
Field of view (km) | 30 × 60 | Diameter of 10.5 | 2.25×1.25 |
Overpass local time | 10:00 | 13:00 | 13:36 |
version | BESD v02.01.01 | ACOS v7.3 | OCO2 r9 |
Profile layers number | 10 | 20 | 20 |
Criteria of data screening | XCO2_quality_flag=0; | XCO2_quality_flag=0; gain=H; land_fraction>90; warn_level<10 | XCO2_quality_flag=0; gain=H; land_fraction>90 |
Name referred hereafter | SCI-XCO2 | GOS-XCO2 | OCO-XCO2 |
Reference | [37] | [38] | [39] |
Sites | Location (Latitude, Longitude) | Coincident Data Pairs | Averaged Bias (ppm) | Averaged Absolute Bias (ppm) | Standard Deviation (ppm) |
---|---|---|---|---|---|
Bialystok | (53.23°N, 23.02°E) | 249 | −0.19 | 0.73 | 0.92 |
Bremen | (53.10°N, 8.85°E) | 260 | 0.21 | 0.97 | 1.25 |
Karlsruhe | (49.10°N, 8.44°E) | 226 | 0.51 | 0.90 | 0.98 |
Orleans | (47.97°N, 2.11°E) | 232 | 0.34 | 0.71 | 0.85 |
Garmisch | (47.48°N, 11.06°E) | 361 | 0.62 | 1.05 | 1.16 |
Park Falls | (45.94°N, 90.27°W) | 499 | 0.00 | 0.74 | 0.96 |
Lamont | (36.60°N, 97.49°W) | 381 | −0.45 | 0.77 | 0.92 |
Tsukuba | (36.05°N, 140.12°E) | 210 | 0.73 | 1.70 | 1.89 |
JPL/Caltech | (34.20°N, 118.18°W) | 243 | −1.06 | 1.19 | 0.97 |
Saga | (33.24°N, 130.29°E) | 204 | −0.33 | 0.76 | 0.91 |
Darwin | (12.43°S, 130.89°E) | 434 | −0.47 | 0.89 | 1.00 |
Wollongong | (34.41°S, 150.88°E) | 341 | 0.09 | 0.58 | 0.75 |
Overall | - | 303 | 0.01 | 0.92 | 1.05 |
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He, Z.; Lei, L.; Zhang, Y.; Sheng, M.; Wu, C.; Li, L.; Zeng, Z.-C.; Welp, L.R. Spatio-Temporal Mapping of Multi-Satellite Observed Column Atmospheric CO2 Using Precision-Weighted Kriging Method. Remote Sens. 2020, 12, 576. https://doi.org/10.3390/rs12030576
He Z, Lei L, Zhang Y, Sheng M, Wu C, Li L, Zeng Z-C, Welp LR. Spatio-Temporal Mapping of Multi-Satellite Observed Column Atmospheric CO2 Using Precision-Weighted Kriging Method. Remote Sensing. 2020; 12(3):576. https://doi.org/10.3390/rs12030576
Chicago/Turabian StyleHe, Zhonghua, Liping Lei, Yuhui Zhang, Mengya Sheng, Changjiang Wu, Liang Li, Zhao-Cheng Zeng, and Lisa R. Welp. 2020. "Spatio-Temporal Mapping of Multi-Satellite Observed Column Atmospheric CO2 Using Precision-Weighted Kriging Method" Remote Sensing 12, no. 3: 576. https://doi.org/10.3390/rs12030576