@article {2587,
	title = {Deglacial ?18O and hydrologic variability in the tropical Pacific and Indian Oceans},
	journal = {Earth and Planetary Science Letters},
	volume = {387},
	year = {2014},
	month = {Jan-02-2014},
	pages = {240 - 251},
	abstract = {Evidence from geologic archives suggests that there were large changes in the tropical hydrologic cycle associated with the two prominent northern hemisphere deglacial cooling events, Heinrich Stadial 1 (HS1; \~{}19 to 15 kyr BP; kyr BP = 1000 yr before present) and the Younger Dryas (\~{}12.9 to 11.7 kyr BP). These hydrologic shifts have been alternatively attributed to high and low latitude origin. Here, we present a new record of hydrologic variability based on planktic foraminifera-derived δ18O of seawater (δ18Osw) estimates from a sediment core from the tropical Eastern Indian Ocean, and using 12 additional δ18Osw records, construct a single record of the dominant mode of tropical Eastern Equatorial Pacific and Indo-Pacific Warm Pool (IPWP) hydrologic variability. We show that deglacial hydrologic shifts parallel variations in the reconstructed interhemispheric temperature gradient, suggesting a strong response to variations in the Atlantic Meridional Overturning Circulation and the attendant heat redistribution. A transient model simulation of the last deglaciation suggests that hydrologic changes, including a southward shift in the Intertropical Convergence Zone (ITCZ) which likely occurred during these northern hemisphere cold events, coupled with oceanic advection and mixing, resulted in increased salinity in the Indonesian region of the IPWP and the eastern tropical Pacific, which is recorded by the δ18Osw proxy. Based on our observations and modeling results we suggest the interhemispheric temperature gradient directly controls the tropical hydrologic cycle on these time scales, which in turn mediates poleward atmospheric heat transport.},
	keywords = {Deglaciation, Eastern Equatorial Pacific, heat transport, Indo-Pacific, δ18O of seawater},
	issn = {0012821X},
	doi = {10.1016/j.epsl.2013.11.032},
	url = {https://doi.org/10.1016/j.epsl.2013.11.032},
	author = {Gibbons, Fern T. and Oppo, Delia W. and Mohtadi, Mahyar and Rosenthal, Yair and Cheng, Jun and Liu, Zhengyu and Linsley, Braddock K.}
}
@article {2585,
	title = {Indonesian vegetation response to changes in rainfall seasonality over the past 25,000 years},
	journal = {Nature Geoscience},
	volume = {7449278721172063253871891072011563523665412739429544323},
	year = {2014},
	month = {Jan-06-2014},
	pages = {513 - 517},
	abstract = {The hydrologic response to climate forcing in the Indo-Pacific warm pool region has varied spatially over the past 25,000 years1, 2, 3, 4, 5. For example, drier conditions are inferred on Java and Borneo for the period following the end of the Last Glacial Maximum, whereas wetter conditions are reconstructed for northwest Australia4. The response of vegetation to these past rainfall variations is poorly constrained. Using a suite of 30 surface marine sediment samples from throughout the Indo-Pacific warm pool, we demonstrate that today the stable isotopic composition of vascular plant fatty acids (δ13Cfa) reflects the regional vegetation composition. This in turn is controlled by the seasonality of rainfall consistent with dry season water stress6. Applying this proxy in a sediment core from offshore northeast Borneo, we show broadly similar vegetation cover during the Last Glacial Maximum and the Holocene, suggesting that, despite generally drier glacial conditions1, 7, there was no pronounced dry season. In contrast, δ13Cfa and pollen data from a core off the coast of Sumba indicate an expansion of C4 herbs during the most recent glaciation, implying enhanced aridity and water stress during the dry season. Holocene vegetation trends are also consistent with a response to dry season water stress. We therefore conclude that vegetation in tropical monsoon regions is susceptible to increases in water stress arising from an enhanced seasonality of rainfall, as has occurred8 in past decades.},
	keywords = {Palaeoclimate, Palaeoecology},
	issn = {1752-0894},
	doi = {10.1038/ngeo2182},
	url = {http://www.nature.com/doifinder/10.1038/ngeo2182},
	author = {Dubois, Nathalie and Oppo, Delia W. and Galy, Valier V. and Mohtadi, Mahyar and van der Kaars, Sander and Tierney, Jessica E. and Rosenthal, Yair and Eglinton, Timothy I. and L?ckge, Andreas and Linsley, Braddock K.}
}
@article {40,
	title = {Mid- to Late-Holocene Australian{\textendash}Indonesian summer monsoon variability},
	journal = {Quaternary Science Reviews},
	volume = {93},
	year = {2014},
	pages = {142-154},
	abstract = {The Australian{\textendash}Indonesian monsoon has a governing influence on the agricultural practices and livelihood in the highly populated islands of Indonesia. However, little is known about the factors that have influenced past monsoon activity in southern Indonesia. Here, we present a \~{}6000 years high-resolution record of Australian-Indonesian summer monsoon (AISM) rainfall variations based on bulk sediment element analysis in a sediment archive retrieved offshore northwest Sumba Island (Indonesia). The record suggests lower riverine detrital supply and hence weaker AISM rainfall between 6000 yr BP and \~{}3000 yr BP compared to the Late Holocene. We find a distinct shift in terrigenous sediment supply at around 2800 yr BP indicating a reorganization of the AISM from a drier Mid Holocene to a wetter Late Holocene in southern Indonesia. The abrupt increase in rainfall at around 2800 yr BP coincides with a grand solar minimum. An increase in southern Indonesian rainfall in response to a solar minimum is consistent with climate model simulations that provide a possible explanation of the underlying mechanism responsible for the monsoonal shift. We conclude that variations in solar activity play a significant role in monsoonal rainfall variability at multi-decadal and longer timescales. The combined effect of orbital and solar forcing explains important details in the temporal evolution of AISM rainfall during the last 6000 years. By contrast, we find neither evidence for volcanic forcing of AISM variability nor for a control by long-term variations in the El Ni{\~n}o-Southern Oscillation (ENSO).},
	issn = {0277-3791},
	doi = {10.1016/j.quascirev.2014.04.006},
	url = {http://www.sciencedirect.com/science/article/pii/S027737911400122X},
	author = {Steinke, Stephan and Mohtadi, Mahyar and Prange, Matthias and Varma, Vidya and Pittauerova, Daniela and Fischer, Helmut W.}
}
@article {2586,
	title = {North Atlantic forcing of tropical Indian Ocean climate},
	journal = {Nature},
	volume = {509},
	year = {2014},
	month = {Jun-04-2016},
	pages = {76 - 80},
	abstract = {The response of the tropical climate in the Indian Ocean realm to abrupt climate change events in the North Atlantic Ocean is contentious. Repositioning of the intertropical convergence zone is thought to have been responsible for changes in tropical hydroclimate during North Atlantic cold spells1, 2, 3, 4, 5, but the dearth of high-resolution records outside the monsoon realm in the Indian Ocean precludes a full understanding of this remote relationship and its underlying mechanisms. Here we show that slowdowns of the Atlantic meridional overturning circulation during Heinrich stadials and the Younger Dryas stadial affected the tropical Indian Ocean hydroclimate through changes to the Hadley circulation including a southward shift in the rising branch (the intertropical convergence zone) and an overall weakening over the southern Indian Ocean. Our results are based on new, high-resolution sea surface temperature and seawater oxygen isotope records of well-dated sedimentary archives from the tropical eastern Indian Ocean for the past 45,000 years, combined with climate model simulations of Atlantic circulation slowdown under Marine Isotope Stages 2 and 3 boundary conditions. Similar conditions in the east and west of the basin rule out a zonal dipole structure as the dominant forcing of the tropical Indian Ocean hydroclimate of millennial-scale events. Results from our simulations and proxy data suggest dry conditions in the northern Indian Ocean realm and wet and warm conditions in the southern realm during North Atlantic cold spells.},
	keywords = {Palaeoceanography, Palaeoclimate},
	issn = {0028-0836},
	doi = {10.1038/nature13196},
	url = {http://www.nature.com/doifinder/10.1038/nature13196},
	author = {Mohtadi, Mahyar and Prange, Matthias and Oppo, Delia W. and De Pol-Holz, Ricardo and Merkel, Ute and Zhang, Xiao and Steinke, Stephan and {\"u}ckge, Andreas}
}
@article {196,
	title = {Glacial to Holocene swings of the Australian-Indonesian monsoon},
	journal = {Nature Geoscience},
	volume = {4},
	year = {2011},
	note = {id: 2012; PT: J; UT: WOS:000293277100016},
	pages = {540-544},
	abstract = {The Australian-Indonesian monsoon is an important component of the climate system in the tropical Indo-Pacific region(1). However, its past variability, relation with northern and southern high-latitude climate and connection to the other Asian monsoon systems are poorly understood. Here we present high-resolution records of monsoon-controlled austral winter upwelling during the past 22,000 years, based on planktic foraminiferal oxygen isotopes and faunal composition in a sedimentary archive collected offshore southern Java. We show that glacial-interglacial variations in the Australian-Indonesian winter monsoon were in phase with the Indian summer monsoon system, consistent with their modern linkage through cross-equatorial surface winds. Likewise, millennial-scale variability of upwelling shares similar sign and timing with upwelling variability in the Arabian Sea. On the basis of element composition and grain-size distribution as precipitation-sensitive proxies in the same archive, we infer that (austral) summer monsoon rainfall was highest during the Bolling-Allerod period and the past 2,500 years. Our results indicate drier conditions during Heinrich Stadial 1 due to a southward shift of summer rainfall and a relatively weak Hadley cell south of the Equator. We suggest that the Australian-Indonesian summer and winter monsoon variability were closely linked to summer insolation and abrupt climate changes in the northern hemisphere.},
	issn = {1752-0894},
	doi = {10.1038/NGEO1209},
	author = {Mohtadi, Mahyar and Oppo, Delia W. and Steinke, Stephan and Stuut, Jan-Berend W. and De Pol-Holz, Ricardo and Hebbeln, Dierk and Lueckge, Andreas}
}
