I'm trying to reconstruct the productivity changes in the southeastern Arabian Sea, during the last glacial period. The foraminiferal proxies suggest an increased glacial productivity in this region. I want to understand the physical forcing, responsible for high surface primary productivity in this region during the last glacial period.
One thing I would suggest that you look into is the "biological pump" or the "plankton multiplier" (see http://plankt.oxfordjournals.org/content/15/9/1053.abstract). One hypothesis is that Fe is a limiting factor in the development of the plankton community. During glacials, the terrestrial vegetation was reduced, increasing the flux of Fe-laden dust to the oceans. This would increase phytoplanton primary productivity, in turn enhancing zooplankton production. This would increase the drawdown of CO2, further exacerbating the glacial by reducing atmospheric CO2.
My co-authors and I provide a partial review of the impact of changing glacial winds on the Agulhas Retroflexion during the LGM in this paper. We discuss the impact of variation in regional winds on marine production and coastal currents off West Africa. The results should help you to hypothesize changes you may see in the Indian coastal currents for comparison with your study.
You can also review the chapter from my dissertation work on the California Current during the LGM for comparison. Primary production can be enhanced by several processes in addition to the Fe hypothesis noted in the prior answer. For example, increased offshore Ekman transport, or increased Ekman pumping via enhanced wind stress curl will increase the nutrient flux to the surface ocean, thereby potentially increasing primary and by inference secondary production.
D Nof, V Zharkov, J Ortiz, N Paldor, W Arruda, E Chassignet, The arrested Agulhas retroflection, Journal of Marine Research 69 (4-6), 4-6, 2011
J Ortiz, A Mix, S Hostetler, M Kashgarian, The California Current of the last glacial maximum: Reconstruction at 42 N based on multiple proxies, Paleoceanography, 12, 191-206, 1997
http://www.ingentaconnect.com/content/jmr/jmr/2011/00000069/F0030004/art00010
http://onlinelibrary.wiley.com/doi/10.1029/96PA03165/abstract;jsessionid=984E24F6C715F59DFF8F2F2FDC1517B4.f01t03
I would also suggest to search for articles on the Eastern Australia Current or the Southern Equatorial Current that circulate offshore Queensland, Australia. Whilst it is a very different region, there is some work on the evolution of these currents since the LGM and this might give you some useful insight (hopefully) on what was going on in India during the last glaciation. Good luck.
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