Wardana, Adhitya Kusuma

The Western Pacific Warm Pool (WPWP) is part of the Indo-Pacific warm pool (IPWP) and characterized by sea surface temperatures (SSTs) greater than 28 ° C. A number of studies have been carried out on rainfall variability of the Western Pacific Warm Pool (WPWP). A recent study combining proxy data and modeling approach from the Southern WPWP thus provides robust evidence on the hydroclimate condition in the region. The δD _wax record demonstrates a shift from the condition during the load deglaciation to weather condition during the holocene.

Expansion of the region of maximum SSTs (> 28 ° C) of the WPWP may have major consequences on the regional and global hydroclimate. This expansion is probably driven by stronger trade winds due to Niña's events and warming in the western Pacific. The expansion of the WPWP may have strengthened the Walker circulation over the region leading to increased convective activity and rainfall. The position of the ITCZ ​​may have been postponed following this expansion.  

Towards a better understanding of the role of the WPWP on rainfall variability in the region itself and on the EAM, the objectives of this PhD thesis are as follows:

• Investigate the long-term variability (millennial to sub-orbital timescales) of rainfall over the WPWP by analyzing a sediment core (GeoB 17405-3) collected from the northern and southern boundaries of the WPWP. Thesis core (Leaf wax δ ¹³ C, C ₃ / C ₄ vegetation) wants to make rainfall changes to the expansions / reductions of the warm pool.
• Investigate the effect of variations in the size and intensity (Leaf wax .DELTA.d _wax / .DELTA.d _P warm) of the pool region on the hydro-climate of the SEAM region by studying sediment core (GeoB 16602) collected off the Pearl River mouth in the South China Sea, Variations circulations in the size and intensity of the warm pool region have been hypothesized to affect the Walker and Hadley (eg, Herbert et al., 2010). The temperature and rainfall records from the two sediment cores will enable us to make changes to the hot pool region and its influence on monsoon rainfall.

Accordingly, we hypothesize that a northward expansion of the WPWP should have affected the hydroclimate of the EAM region by increasing rainfall. GeoB 16602 located in the Pearl River Mouth should be robustly record this signature. Thus, by reconstructing past rainfall variability from the WPWP and EAM region we can examine the role of the WPWP in determining the hydroclimate of the SEAM region.