Interpretation of a temperature and salinity section at 180 degrees longitude in relation to the ENSO cycle in the equatorial Pacific for March 2023

Abstract

El Niño-Southern Oscillation (ENSO), which is the cycle consisting of El Niño and La Niña has major global impacts on climate. El Niño and La Niña are characterized by large changes in temperature in the equatorial Pacific, and understanding these changes is vital for a broader understanding of global climate. The goal of this study is to place data collected on a cruise conducted in early March 2023 in a broader context, comparing features such as 20°C isotherm depth, surface temperature, and barrier layers. Data used for this paper was collected from March 3rd to March 7th of 2023, along the International Date Line from 5°N to 5°S. Cruise data was more similar to La Niña conditions than El Niño conditions, but still had significant differences when compared to La Niña data collected from a Tropical Atmosphere Ocean (TAO) array. Thermoclines were deeper in El Niño conditions when compared to La Niña conditions, but the cruise data had thermoclines significantly deeper than La Niña data in the TAO. A barrier layer was found at 5-4°N, and a salinity maximum was found near 1-5°S, which matched observations reported in a previous study.