believe that friendships made over two-hour lunches, food trips, Friday-night lehpak sessions, running marathons, exploring new places, welcoming babies and marriages, listening to each other's drama, challenging each other's brains or just by laughing at and with each other, is the best kind of friendship one can ever have. Thank you for the random acts of kindness, the constant support and encouragements when I needed it the most, the criticisms and reality-checks when I go blind in my judgements and the endless comic relief. You all have a place in my heart. To Rovi Velasquez, Apple Jarical, Aurora Molina, and Jillian Gabo, thank you for always being present. To Daphnie Galvez, Zoan Macalalad, Ronald Lloren and Yvainne Sta. Maria, thank you for the constant checks and encouragements even from afar.My deepest gratitude also goes to my family, Daddy, Mommy, Ate Yel, Beck and Kuya Patrick. Thank you for your unfailing love, all-out support, understanding and for always being proud of me. To Ralph, for being my home away from home, I can't thank you enough for always reassuring your confidence in me, for the conscious effort to make me smile and feel loved. Let's keep on dreaming and achieving together.Above all, my praises to our Lord for the grace, love, and strength, for blessing me with this opportunity and surrounding me with these wonderful people. Maraming salamat! 2.4.2. Inter-annual calibrations 2.4.3. SSS variability using Porites δ 18 O 2.4.4. Application of calibration equation and comparison to SOI variability 2.5 Conclusions 2.6 References Chapter 3. Late 19 th century coral record of the Pacific Decadal Oscillation and its possible climatic control on the tropical western Pacific salinity variability 100 Abstract 3.1 Introduction 3.2 Methods 3.2.1. Study site and coral sampling 3.2.2. Coral subsampling 3.2.3. Sr/Ca analysis 3.2.4. δ 18 O analysis 3.2.5. Chronology development 3.2.6. SST and SSS reconstructions 3.2.7. Data analysis 3.3 Results 3.3.1. Sr/Ca-SST reconstruction 3.3.2. Dry and wet season δ 18 Oc-SSS reconstruction 3.4 Discussion 3.4.1. Climatic controls on SST variability 3.4.2. Climatic controls on SSS variability 3.5 Conclusions 3.6 References Chapter 4. Coral-based records of sea surface temperature and salinity variability in the Luzon Strait since the end of the Little Ice Age 138 Abstract 4.1 Introduction 4.2 Methods 4.2.1. Study site and coral sampling 4.2.2. Coral subsampling 4.2.3. Sr/Ca and δ 18 O measurements 4.2.3.1 Dry-season δ 18 O measurements 4.2.4. Instrumental data 4.2.5. Chronology development 4.2.6. Data analysis 4.3 Results 4.3.1 Sr/Ca-SST 4.3.1.1. Monthly calibration 5 4.3.1.2. Inter-annual calibrations 4.3.1.3. Interannual winter SST reconstruction 4.3.1.4. Influences on the observed winter SST variability 4.3.2 δ 18 O-SSS 4.3.2.1. Monthly calibration 4.3.2.2. Inter-annual calibrations 4.3.2.3. Inter-annual dry season SSS reconstruction 4.3.2.4. Influences on the observed dry season SSS variability 4.4 Discussion 4.5 Conclusions 4.6 References Chapter 5. Inter-annu...