Abstract
A modified technique for calculating the amplitude-phase characteristics of the seasonal cycle and long-term trends in the intensity of upwelling is discussed based on an analysis of the minimum (maximum in the absolute value) values of the thermal upwelling index (TUI). The TUI is calculated as the difference in satellite sea surface temperature (SST) between the coastal and offshore zones in the areas of large-scale oceanic upwelling. The proposed technique is used to calculate the climatic variability parameters of the Eastern Boundary Upwelling Systems (EBUS’s). The seasonal variations of the TUI calculated in this approach are in better agreement with the intra-annual variability of the upward motions of the wind origin than changes in the TUI values averaged over climatic masks. The long-term TUI trends obtained by using the modified method are more significant than those calculated in climatic masks and confirm the intensification of upwelling in the last ~35 years.
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REFERENCES
Bakun, A., Global climate change and intensification of coastal ocean upwelling, Science, 1990, vol. 247, pp. 198–201. https://doi.org/10.1126/science.247.4939.198
Bakun, A., Black, B.A., Bograd, S.J., García-Reyes, M., Miller, A.J., Rykaczewski, R.R., et al., Anticipated effects of climate change on coastal upwelling ecosystems, Curr. Clim. Change Rep., 2015, vol. 1, pp. 85–93. https://doi.org/10.1007/s40641-015-0008-4
Belmadani, A., Echevin, V., Codron, F., Takahashi, K., and Junquas, C., What dynamics drive future wind scenarios for coastal upwelling off Peru and Chile?, Clim. Dyn., 2014, vol. 43, nos. 7–8, pp. 1893–1914.
Cade, B. and Noon, B., A gentle introduction to quantile regression for ecologists, Front. Ecol. Environ., 2003, vol. 1, pp. 412–420. https://doi.org/10.1890/1540-9295(2003)001[0412:AGITQR]2.0.CO;2
Carr, M.E., Estimation of potential productivity in Eastern Boundary Currents using remote sensing, Deep-Sea Res., Part II, 2002, vol. 49, nos. 1–3, pp. 59–80.
Carr, M.E. and Kearns, E.J., Production regimes in four Eastern Boundary Current systems, Deep-Sea Res., Part II, 2003, vol. 50, nos. 22–26, pp. 3199–3221.
Chavez, F.P. and Messie, M., A comparison of eastern boundary upwelling ecosystems, Prog. Oceanogr., 2009, vol. 83, nos. 1–4, pp. 80–96. https://doi.org/10.1016/j.pocean.2009.07.032
Chelton, D.B., deSzoeke, R.A., Schlax, M.G., El Naggar, K., and Siwertz, N., Geographical variability of the first baroclinic Rossby radius of deformation, J. Phys. Oceanogr., 1998, vol. 28, no. 3, pp. 433–460. https://doi.org/10.1175/1520-0485(1998)028<0433:GVOTFB>2.0.CO;2
García-Reyes, M., Sydeman, W.J., Schoeman, D.S., Ry-kaczewski, R.R., Black, B.A., Smit, A.J., and Bograd, S.J., Under pressure: Climate change, upwelling, and eastern boundary upwelling ecosystems, Front. Mar. Sci., 2015, vol. 2, id 109. https://doi.org/10.3389/fmars.2015.00109
Gill, A., Atmosphere–Ocean Dynamics, London: Academic, 1982; Moscow: Mir, 1986.
Huyer, A., Coastal upwelling in the California current system, Prog. Oceanogr., 1983, pp. 259–284. https://doi.org/10.1016/0079-6611(83)90010-1
IPCC, 2014: Climate Change 2014: Synthesis Report., Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, Pachauri, R.K. and Meyer, L.A., Eds., Geneva: IPCC, 2014.
Koenker, R., Quantile Regression, Cambridge: Cambridge Univ. Press, 2005.
Koenker, R. and Bassett, G., Regression quantiles, Econometrica, 1978, vol. 46, no. 1, pp. 33–50.
Koenker, R. and Hallock, K., Quantile regression, J. Econ. Perspect., 2001, vol. 15, pp. 143–156.
Pauly, D. and Christensen, V., Primary production required to sustain global fisheries, Nature, 1995, vol. 374, pp. 255–257. https://doi.org/10.1038/374255a0
Philander, S.G., El Niño, La Niña and the Southern Oscillation, San Diego: Academic Press, 1990.https://doi.org/10.1126/science.248.4957.904
Polonsky, A.B. and Serebrennikov, A.N., On the change in the ocean surface temperature in the Benguela upwelling region. Part I: Season cycle, Izv., Atmos. Ocean. Phys., 2019, vol. 55, no. 9, pp. 1050–1059. https://doi.org/10.1134/S0001433819090391
Polonsky, A.B. and Serebrennikov, A.N., On the change in the sea surface temperature in the Benguela Upwelling Region: Part II. Long-term tendencies, Izv., Atmos. Ocean. Phys., 2020a, vol. 56, no. 9, pp. 970–978. https://doi.org/10.1134/S0001433820090200
Polonsky, A.B. and Serebrennikov, A.N., Intensification of eastern boundary upwelling systems in the Atlantic and Pacific oceans, Russ. Meteorol. Hydrol., 2020b, vol. 45, no. 5, pp. 422–429.
Seabold, S. and Perktold, J., Statsmodels: Econometric and statistical modeling with python, in Proceedings of the 9th Python in Science Conference, 2010. http://conference. scipy.org/proceedings/scipy2010/pdfs/seabold.pdf.
Serebrennikov, A.N., An improved technique for the retrieval of coastal upwelling indices from satellite data, Sovrem. Probl. Distantsionnogo Zondirovaniya Zemli Kosmosa, 2018, vol. 15, no. 5, pp. 44–51.
Upwelling: Mechanisms, Ecological Effects and Threats to Biodiversity, Fischer, W.E. and Green, A.B., Eds., Nova Sci. Publ., 2013, pp. 59–76.
ACKNOWLEDGMENTS
We are grateful to an anonymous reviewer for their encouraging report and constructive remarks.
Funding
This study was carried out as part of State Task no. 0012-2019-0002 (“Basic Studies of the Processes in a Climatic System that Determine the Spacetime Variability of the Natural Environment of Global and Regional Scales.”)
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Polonsky, A.B., Serebrennikov, A.N. Modified Technique for Calculating the Parameters of Climatic Variability of Upwelling by Thermal Index. Izv. Atmos. Ocean. Phys. 57, 1137–1145 (2021). https://doi.org/10.1134/S0001433821090590
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DOI: https://doi.org/10.1134/S0001433821090590