S1. Background reading - Anthony

[eeholmes]

Background reading

Instructions: start with these. You don't have to understand or follow all the details. Get the jist of what researchers think will happen to upwelling as the climate warms. Also you don't have to read all but do read the 2 Bakun ones. Add or substitute other reading you do for background in the comments.

Bakun, Andrew. 1990. Global Climate change and intensification of coastal ocean upwelling.” Science 247: 198–201. http://www.jstor.org/stable/2873492.

Bakun, A. et al. 2015. Anticipated effects of climate change on coastal upwelling ecosystems. Curr. Clim. Change Rep. 1, 85–93.

García-Reyes M, Sydeman WJ, Schoeman DS, Rykaczewski RR, Black BA, Smit AJ and Bograd SJ. 2015. Under pressure: climate change, upwelling, and eastern boundary upwelling ecosystems. Front. Mar. Sci. 2:109. doi: 10.3389/fmars.2015.00109

Garreaud, R. D. & Falvey, M. 2009. The coastal winds off western subtropical South America in future climate scenarios. Int. J. Climatol. 29, 543–554.

Rykaczewski, R. R. et al. 2015. Poleward displacement of coastal upwelling-favorable winds in the ocean’s eastern boundary currents through the 21st century. Geophysical Research Letters 42, 6424–6431.

Wang, D., Gouhier, T. C., Menge, B. A. & Ganguly, A. R. 2015. Intensification and spatial homogenization of coastal upwelling under climate change. Nature 518, 390–394 (2015).

Xiu, P., Chai, F., Curchitser, E.N. et al. 2018. Future changes in coastal upwelling ecosystems with global warming: The case of the California Current System. Sci Rep 8, 2866. https://doi.org/10.1038/s41598-018-21247-7

[zhengx25-1976320]

1. upwelling system has seasonal cycle in temperate latitude and tends to be all year round in tropical area.
2. Characterized by fog. We used to use SST to study upwelling, is it possible to study it by barometric pressure, or wind?
3. Built up of CO2 lead to inhibition of nighttime cooling and enhancement of daytime heating should intensify the continental lows -> greater onshore offshore atmospheric pressure gradient -> stronger wind -> accelerated upwelling systems.
4. Wind observation is irregularly distributed in time and place.
5. In Peru, due to low latitude location and weakened geostrophic constraint, why upwelling index computation are not appropriate?
6. Study the effect of EI Nino on upwelling system?
7. Care must be taken in using evidence from previous warm epochs. The dynamic ocean process that determines temperature could be fundamentally altered.
8. It is unclear whether increased primary production promote reproductive success.
9. There is competing tendency. Many of the consequence of global change to marine ecosystem should be analyzed upon the relative importance, local situation of this competing effects.

[zhengx25-1976320]

second backup:

1. Hadley Cells changed in latitude and intensity. expand poleward in both hemispheres. asymmetric response of surface temperatures in the northern (more land) and southern (less land) mid-latitude oceans, combined with tropical warming, the Northern Hemisphere Hadley Cell is predicted to decrease in intensity while that of the Southern Hemisphere will increase in intensity.

Under pressure: climate change, upwelling, and eastern boundary upwelling ecosystems:

1.coastal upwelling-favorable winds in poleward portions of EBUS have intensified and will continue to do so in the future. 2.Impressive: Eastern Boundary Upwelling Systems (EBUS) are biologically productive marine regions covering <1% of the ocean area, but providing up to 20% of the world's capture fisheries 3.weaker upwelling may limit nutrient enrichment of the photic zone with potentially negative impacts on primary production. By contrast, stronger upwelling may increase nutrient input, but at the same time increase offshore transport. Other impacts include increased turbulence with increased winds, and changes in chemical mechanisms, e.g., ocean acidification and deoxygenation, that may affect productivity.

What point in the middle yields to the highest productivity?

4.the low confidence in predictions regarding the ecological future of EBUS is driven more heavily by uncertainty surrounding the potentially counteracting effects of intensifying winds on the one hand, and increasing thermal stratification on the other. The former might lead to enhanced nutrient influx, while the latter could limit it.

5.Failure: (1) the small amplitude of unidirectional wind trends relative to amplitudes of seasonal, interannual, and decadal wind variability, and (2) the short duration of most observational time series relative to decadal variability. Further complications include (i) disparate data sets examined, (ii) inconsistencies in data treatment, including analyses of warm season vs. annual means as well as variable observation periods or quality and density of data, and (iii) changes in measurement techniques or models used to interpolate or reanalyze data. Based on these differences, concluded low confidence in common trends in upwelling-favorable winds. 6.we still cannot attribute coastal wind intensification in EBUS to global warming because we cannot discount the role of multi-decadal climate variability in the observed trends 7.study decadal variability and global warming?

8.inclusion: the only generality that can be made is that upwelling-favorable winds tend to be most intense during the warm months of the year (Huyer, 1983; Nelson and Hutchings, 1983). Beyond this, however, the timing, intensity, and persistence of upwelling-favorable winds are remarkably variable within and among EBUS. So, choose a specific location to study it?