Investigation of Atmospheric Effects on Retrieval of Sun-Induced Fluorescence Using Hyperspectral Imagery
Abstract
:1. Introduction
2. Materials and Methods
2.1. Generation of Simulated Data
2.2. Field Experiments
2.3. Method of Retrieving SIF
2.3.1. Damm Method
2.3.2. DOAS
2.3.3. Braun Method
3. Results
3.1. Sensitivity Analysis
3.2. Effects of Atmospheric Parameters on the Oxygen-Absorption Depth in the O2-A and O2-B Bands
3.2.1. Solar Zenith Angle
3.2.2. Sensor Height
3.2.3. Elevation
3.2.4. VIS
3.2.5. Water Content
4. Discussion
4.1. Comparison of the Three Methods of Retrieving Fluorescence
4.2. Using the Damm Method to Retrieve Fluorescence from Airborne Imagery
5. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
Abbreviations:
SIF | solar-induced chlorophyll fluorescence |
Fs | fluorescence measured by PAM-2500 |
FLEX | Fluorescence Explorer |
TOA | top of atmosphere |
VNIR | visible and near-infrared |
SZA | sun zenith angle |
VIS | visibility |
FLD | Fraunhofer line depth |
DOAS | differential optical absorption spectroscopy |
Cab | chlorophyll a+b content |
Fqe | fluorescence quantum yield efficiency |
LAI | leaf area index |
SCOPE Fs | fluorescence radiance at 761 nm |
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Parameter | Value | Unit | Description |
---|---|---|---|
SZA | 10, 30, 50,70 | Degree | Sun zenith angle |
Sensor height | 0.5, 1.0, 10, 50, 100, 704 | km | Position of sensor |
Elevation | 0.0, 0.05, 0.1 | km | Altitude of surface relative to sea level |
VIS | 10, 20, 30, 40, 50 | km | Surface meteorological range |
Water content | 0.5, 2.0, 3.5 | gm/cm2 | Vertical water vapor column |
Parameter | Value | Unit | Description |
---|---|---|---|
Cab | 20, 40, 60, 80 | µg/cm2 | Chlorophyll α + b content |
Fqe | 0.02, 0.04, 0.06 | -- | fluorescence quantum yield efficiency |
LAI | 1, 2, 4, 6 | m2/m2 | leaf area index |
Parameter | Value |
---|---|
Spectral range | 400–970 nm |
Spectral resolution | 3.3 nm |
Spectral sampling interval | 0.67 nm |
Focal length | 18.5 mm |
FOV | 36.7 degrees |
IFOV | 0.036 degrees |
Swath width | 0.66 × altitude |
Ground resolution @ 400-m altitude | 0.32 m |
SNR | 1250:1 (maximum theoretical) |
Reference Paper | Band | Method | Application |
---|---|---|---|
Fraunhofer lines | |||
Joiner et al. (2011) [24] | 769.9–770.25 nm (K I) | GOSAT TANSO-FTS | |
Joiner et al. (2012) [35] | 769.9–770.25 nm 758.45–758.85 nm 863.5–868.5 nm (Ca II) | GOSAT SCIAMACHY | |
Guanter et al. (2012) [36] | 755–775 nm (K I) | GOSAT-FTS | |
N. Khosravi (2012) [46] | 660–683 nm 745–758 nm | DOAS | |
Guanter et al. (2013) [37] | 745–759 nm (Fraunhofer line) 717–759 nm (red edge) 745–780 nm (O2-A band) 717–780 nm (full-range) | GOSAT-FTS HR4000 | |
P. Köhler et al. (2014) [38] | 590–790 nm (GOME-2) 604–805 nm( SCIAMACHY) | GOME-2 SCIAMACHY | |
P. Köhler et al. (2015) [39] | 755–759 nm | GARLiC | GOSAT |
Oxygen-absorption band | |||
Guanter et al. (2007) [12] | 760.6 nm 753.8 nm | FLD MODTRAN-4 | MERIS CASI-1500 |
Damm et al. (2010) [11] | 760.6 nm 755 nm | FLD MODTRAN-4 | ASD |
Guanter et al. (2010) [29] | 745–775 nm 672–702 nm | SFM FLD-S | FIMAS-like TOA radiance |
Mazzoni et al. (2010) [47] | 677–697 nm 750–770 nm | DS = NSENSOR_RADn-NSENSOR_RADm | OCO TANSO-FTS |
Frankenberg et al. (2011) [31] | O2-A | GOSAT OCO-2 | |
Joiner et al. (2013) [32] | 715–745 nm 750–780 nm | GOME-2 | |
Damm et al. (2014) [30] | O2-A | 3FLD MODTRAN-5 | ASD |
Braun (2014) [33] | O2-A | F = AV -ANV | EO-1 |
Liu et al. (2015) [34] | 650–800 nm | F-SFM | simulated data |
Parameter | Variation Range | Correlation with Depth | Depth Variation | |
---|---|---|---|---|
O2-A | O2-B | |||
SZA | 10–70 | + | 111.4% | 27.5% |
Sensor height | 0.1–704 km | + | 77.1% | 32.6% |
Elevation | 0.0–0.1 km | - | 2.80% | 0.90% |
VIS | 10–50 km | - | 17.2% | 22.4% |
Water content | 0.5–3.5 gm/cm2 | + | 0.63% | 0.01% |
Methos vs. SCOPE SIF | Fitting Window | |||
---|---|---|---|---|
O2-A Band | O2-B Band | |||
R2 | RMSE | R2 | RMSE | |
Damm vs. SCOPE SIF | 0.99 | 0.13 | 0.88 | 0.84 |
Braun vs. SCOPE SIF | −0.20 | 1.37 | −0.73 | 5.31 |
DOAS vs. SCOPE SIF | 0.78 | 0.40 | 0.66 | 1.58 |
Indicator | Band | Method | SZA | Sensor Height | Elevation | VIS | Water Content |
---|---|---|---|---|---|---|---|
10°–70° | 0.5–704 km | 0.0–0.1 km | 10–50 km | 0.5–3.5 gm/cm2 | |||
Variation | O2-A | Damm | −9.80% | 2.30% | 0.00% | −0.06% | 0 |
DOAS | 0.00% | 0.00% | 0.00% | 61.80% | 0.44% | ||
O2-B | Damm | 19.40% | 13.50% | 0.12% | 0.62% | 0.41% | |
DOAS | 0.03% | 0.12% | 113% | 0.66% | 0.01% | ||
ΔFW/m2/µm/sr | O2-A | Damm | −0.13 | 0.03 | 0.0004 | −0.0008 | 0 |
DOAS | −0.0003 | −0.00018 | 0 | −0.74 | 0 | ||
O2-B | Damm | −0.88 | 0.49 | 0.005 | 0.03 | −0.02 | |
DOAS | 0 | 0.004 | −3.9 | −0.002 | 0 |
Parameter | Value | Unit |
---|---|---|
SZA | 30.10 | degree |
Water content | 3.97 | gm/cm2 |
VIS | 44.48 | km |
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Ni, Z.; Liu, Z.; Li, Z.-L.; Nerry, F.; Huo, H.; Sun, R.; Yang, P.; Zhang, W. Investigation of Atmospheric Effects on Retrieval of Sun-Induced Fluorescence Using Hyperspectral Imagery. Sensors 2016, 16, 480. https://doi.org/10.3390/s16040480
Ni Z, Liu Z, Li Z-L, Nerry F, Huo H, Sun R, Yang P, Zhang W. Investigation of Atmospheric Effects on Retrieval of Sun-Induced Fluorescence Using Hyperspectral Imagery. Sensors. 2016; 16(4):480. https://doi.org/10.3390/s16040480
Chicago/Turabian StyleNi, Zhuoya, Zhigang Liu, Zhao-Liang Li, Françoise Nerry, Hongyuan Huo, Rui Sun, Peiqi Yang, and Weiwei Zhang. 2016. "Investigation of Atmospheric Effects on Retrieval of Sun-Induced Fluorescence Using Hyperspectral Imagery" Sensors 16, no. 4: 480. https://doi.org/10.3390/s16040480
APA StyleNi, Z., Liu, Z., Li, Z.-L., Nerry, F., Huo, H., Sun, R., Yang, P., & Zhang, W. (2016). Investigation of Atmospheric Effects on Retrieval of Sun-Induced Fluorescence Using Hyperspectral Imagery. Sensors, 16(4), 480. https://doi.org/10.3390/s16040480