Coastal Upwelling Front Detection off Central Chile (36.5–37°S) and Spatio-Temporal Variability of Frontal Characteristics
Abstract
:1. Introduction
2. Materials and Methods
2.1. Observational Datasets
2.2. Upwelling Front Detection Method
2.2.1. General Methodology
2.2.2. Front Detection
2.2.3. Determination of the Front Characteristics
2.3. Statistical Validation of the Detected Fronts
3. Results
3.1. Atmospheric and Oceanic Forcing
3.1.1. Local Atmospheric Forcing and Its Impact on the SST
3.1.2. Coastal Jet Circulation
3.2. The Front Characteristics Variability
3.2.1. Probability of Detecting a Front
3.2.2. Front Intensity
3.2.3. Front Position
4. Discussion
4.1. Strength and Limitations of the Front Detection Method
4.1.1. Strength
4.1.2. Limitations
4.2. Comparison of the Front Detection Method with Previous Works
4.2.1. Consistency with the Front Definition by Cayula and Cornillon (1992)
4.2.2. Consistency with In Situ Measurement
4.3. Front Characteristics Variability off Central Chile
4.3.1. Errors and Uncertainties
4.3.2. Jet Configuration and Front Position
4.3.3. Reinforcement of the Upwelling Front in EBUS
5. Conclusions
Author Contributions
Acknowledgments
Conflicts of Interest
Abbreviations
EBUS | Eastern Boundary Upwelling System |
CTZ | Coastal Transition Zone |
SST | Sea Surface Temperature |
HCS | Humboldt Current System |
ENSO | El Niño Southern Oscillation |
SSH | Sea Surface Height |
Probability Density Function | |
MUR | Multi-scale Ultra-high Resolution |
NOCS | National Oceanography Center Southampton |
ONI | Oceanic Niño Index |
Appendix A. Strong Cross-Shore Gradient Zone “Frontal Zone”) Identification
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10 January 2004 | 0.9 | 5.1 |
19 May 2004 | 0.8 | 4.4 |
02 March 2005 | 0.9 | 5.1 |
10 March 2005 | 0.9 | 5.1 |
05 April 2005 | 0.8 | 4.6 |
11 January 2005 | 0.8 | 4.8 |
15 January 2007 | 0.7 | 3.5 |
23 March 2007 | 0.8 | 4.0 |
10 March 2009 | 0.9 | 5.8 |
13 December 2010 | 0.9 | 5.0 |
14 November 2016 | 0.9 | 6.1 |
R(,) | R(,) | R(,) | |
---|---|---|---|
monthly mean | 0.86 | 0.78 | 0.77 |
yearly mean | 0.88 | 0.89 | 0.64 |
climatological seasonal cycle | 0.93 | 0.93 | 0.97 |
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Oerder, V.; Bento, J.P.; Morales, C.E.; Hormazabal, S.; Pizarro, O. Coastal Upwelling Front Detection off Central Chile (36.5–37°S) and Spatio-Temporal Variability of Frontal Characteristics. Remote Sens. 2018, 10, 690. https://doi.org/10.3390/rs10050690
Oerder V, Bento JP, Morales CE, Hormazabal S, Pizarro O. Coastal Upwelling Front Detection off Central Chile (36.5–37°S) and Spatio-Temporal Variability of Frontal Characteristics. Remote Sensing. 2018; 10(5):690. https://doi.org/10.3390/rs10050690
Chicago/Turabian StyleOerder, Vera, Joaquim P. Bento, Carmen E. Morales, Samuel Hormazabal, and Oscar Pizarro. 2018. "Coastal Upwelling Front Detection off Central Chile (36.5–37°S) and Spatio-Temporal Variability of Frontal Characteristics" Remote Sensing 10, no. 5: 690. https://doi.org/10.3390/rs10050690