Temperature, Wind, Cloud, and the Postglacial Tree Line History of Sub-Antarctic Campbell Island

Campbell Island, located 600 km south of New Zealand, exhibits a unique postglacial tree line history that is decoupled from Southern Ocean temperature trends. The study reveals that while ocean temperatures were warmer between 12,500 and 9,000 years ago, the island's tree lines did not rise due to weaker westerlies, which allowed for the intrusion of warmer, cloudier northern airmasses. This phenomenon reduced solar radiation and increased atmospheric humidity, suppressing tree growth. Conversely, stronger, cooler westerlies during the Holocene facilitated clearer skies, drier air, and rising tree lines. The research uses pollen records from three peat cores to reconstruct vegetation changes over 17,000 years, providing insights into the complex interplay between climate, wind patterns, and ecological dynamics in sub-Antarctic regions.

McGlone, M. S., Wilmshurst, J. M., Richardson, S. J., Turney, C. S. M., & Wood, J. R. (2019). Temperature, Wind, Cloud, and the Postglacial Tree Line History of Sub-Antarctic Campbell Island. Forests, 10(11), 998. https://doi.org/10.3390/f10110998