English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

. The plains of northwest South Asia receive rainfall during both the Indiansummer (June–September) and winter (December–March) monsoon. Researchershave long attempted to deconstruct the influence of these precipitationregimes in paleoclimate records, in order to better understand regionalclimatic drivers and their potential impact on human populations. Themid–late Holocene transition between 5.3 and 3.3 ka is of particularinterest in this region because it spans the period of the Indus Civilizationfrom its early development, through its urbanization, and onto eventualtransformation into a rural society. An oxygen isotope record of thesurface-dwelling planktonic foraminifer Globigerinoides ruber fromthe northeast Arabian Sea provided evidence for an abrupt decrease inrainfall and reduction in Indus River discharge at 4.2 ka, which the authorslinked to the decline in the urban phase of the Indus Civilization(Staubwasser et al., 2003). Given the importance of this study, we used thesame core (63KA) to measure the oxygen isotope profiles of two otherforaminifer species at decadal resolution over the interval from 5.4 to3.0 ka and to replicate a larger size fraction of G. ruber thanmeasured previously. By selecting both thermocline-dwelling(Neogloboquadrina dutertrei) and shallow-dwelling(Globigerinoides sacculifer) species, we provide enhanced detail ofthe climatic changes that occurred over this crucial time interval. We foundevidence for a period of increased surface water mixing, which we suggest wasrelated to a strengthened winter monsoon with a peak intensity over 200 yearsfrom 4.5 to 4.3 ka. The time of greatest change occurred at 4.1 ka whenboth the summer and winter monsoon weakened, resulting in a reduction inrainfall in the Indus region. The earliest phase of the urban Mature Harappanperiod coincided with the period of inferred stronger winter monsoon between4.5 and 4.3 ka, whereas the end of the urbanized phase occurred some timeafter the decrease in both the summer and winter monsoon strength by 4.1 ka.Our findings provide evidence that the initial growth of large Indus urbancenters coincided with increased winter rainfall, whereas the contraction ofurbanism and change in subsistence strategies followed a reduction inrainfall of both seasons.

Indian winter and summer monsoon strength over the 4.2 ka BP event in foraminifer isotope records from the Indus River delta in the Arabian Sea