Work

What Causes the Hemispheric Difference in the Asymmetry of the Temperature Annual Cycle?

Year: 2025

Type: article

Abstract: Previous studies have noted the asymmetry in the annual cycle of zonal mean surface air temperature, defined as the difference in the lengths of warming and cooling periods. Pronounced north‐south hemispheric differences in this asymmetry, by up to 40 days, were attributed to the eccentricity of Earth's orbit. However, we propose that the dominant factor comes from the difference in the land‐sea fraction between hemispheres, because the asymmetry is strongly influenced by the annually varying heat capacity and land‐sea interactions. The oceanic temperature annual cycle generally features a longer cooling period than warming due to the seasonal variation in ocean mixed layer depth, and exhibits the opposite situation when there is seasonal sea ice. Land‐sea interactions impact the zonal mean temperature annual cycle by resulting in an earlier winter trough of the downstream oceanic temperature and delaying the summer peak in west coasts.

Source: Geophysical Research Letters

DOI: 10.1029/2024gl112611

Authors: Fucheng Yang, John C. H. Chiang, Zhaohua Wu

Institutions: Florida State University, Georgia Institute of Technology, University of California, Berkeley

Language: English

Topic: Climate variability and models

Subfield: Global and Planetary Change

Field: Environmental Science

Domain: Physical Sciences

SDG: Climate action

Open Access status: gold

Estimated APC paid: $3,190