Muhammad Yusuf Awalud­din

Millennial to Centennial scale variability of the Indonesian Throughflow source waters from the Last Glacial Maximum to present

The In­done­sian Through­flow (ITF) refers to the oceanic trans­port of warm wa­ter from the Pa­cific to the In­dian Ocean through the In­done­sian sea­ways. It plays an im­port­ant part in the global ocean and cli­mate reg­u­la­tions. Con­cern­ing pa­leocean­o­graphic re­search, the exit portal of the ITF has been tar­geted in many years. However, less is known about past vari­ations in the ITF source wa­ters be­fore en­ter­ing the In­done­sian Seas. This is a sig­ni­fic­ant gap in the over­all as­sess­ment of the ITF vari­ab­il­ity in the past and its modi­fic­a­tion within the In­done­sian Seas.

The re­search ob­ject­ives are to quantify past sea sur­face tem­per­at­ure (SST) changes along the main path of the ITF source wa­ters and to re­con­struct the full column oceanic trans­port of the ITF from Last Gla­cial Max­imum to late Holo­cene. Sed­i­ment samples have been re­covered from the south­ern part of Mindanao as the en­trance portal of the ITF. Here, I use plank­tic fo­raminifera as proxy such as G. ruber, P. ob­liquiloc­u­lata, and benthic fo­raminifera such as C.wuellerstorfi and Hoeglandina el­eg­ans.

In or­der to get chro­no­lo­gical con­trol, Ac­cel­er­ator Mass Spec­tro­metry (AMS) ra­diocar­bon dat­ing has been con­duc­ted to es­tab­lish the age model of the cores. Car­bon dat­ing of these shells, or tests, will put these find­ings throughout the Qua­tern­ary period, such as the Last Gla­cial Max­imum (LGM) 20,000 years and more re­cent events. Other ef­forts such as stable iso­topes and Mg/​Ca ra­tio will al­low us to un­der­stand the past modi­fic­a­tion of the en­trance way of the ITF. Res­ults are ex­pec­ted to con­trib­ute to un­rav­el­ling the vari­ab­il­ity of the ITF in the past and be of great in­terest for the pa­leocean­o­graphic com­munity.