The response of Pacific decadal variability to global warming

Abstract

Pacific Decadal Variability (PDV) plays a pivotal role in understanding climate shifts. This study focuses on investigating the primary components of PDV, namely, the Pacific Decadal Oscillation (PDO) and the North Pacific Gyre Oscillation (NPGO). These components are defined as the first and second principal modes of the North Pacific sea surface temperature anomaly field. Our analysis indicates that under the influence of global warming, both PDO and NPGO exhibit a weakening of the amplitude and a shortening of the period. Furthermore, NPGO demonstrates a more pronounced response to a 2C warming scenario compared to a 1.5C increase. This heightened sensitivity is attributed to the accelerated propagation of Rossby waves, a consequence of enhanced ocean stratification. The findings of this research contribute to the establishment of a scientific foundation for informed environmental policy development, facilitating the promotion of environmental conservation and sustainable development.