The Cooperative Institute for Climate, Ocean, and Ecosystem Studies

I am majoring in Earth & planetary sciences at Johns Hopkins University. During this summer, we investigate ecosystem dynamics near the “eastern” edge of the warm pool.

The western Pacific warm pool contains the warmest seawater and plays a crucial role in the climate system (e.g. Chen et al., 2004). During El Niño events, the warm pool expands eastward, and the equatorial upwelling is reduced in the eastern Pacific. We use measurements from the Tropical Pacific Observing System (TPOS) Uncrewed Surface Vehicle mission during the 2023 El Niño to investigate marine ecosystem dynamics near the “eastern” edge of the warm pool, which is defined using the 29℃ isotherm in this study (e.g. Peng et al., 2025). We analyzed two cases when the Saildrone Inc. uncrewed surface vehicle “saildrone” was entering the warm pool. Based on variations in the mean volume backscattering strength, we infer that part of organisms in the upper 50 m layer moved downward and formed a distinct layer from 100-150 m while and after entering the warm pool during the nighttime. Backscattering during the daytime increased in the deep scattering layer (400-600 m) after entering the warm pool, which is likely due to either an increase in biomass or to a change in the composition of this layer in terms of organisms (Simmonds & MacLennan, 2005). Future work includes analyzing other cases when the “saildrone” was entering the warm pool and using ocean reanalysis models to investigate the potential driver.

I learnt more about state-of-the-art instrumentation and had a great experience this summer!

Project Introduction

Research Poster