Geographic variability in dust and temperature in climate scaling regimes over the Last Glacial Cycle

Reyes, Nicolas Acuna; van't Wout, Elwin; Lovejoy, Shaun; Lambert, Fabrice

Abstract

Temperature and mineral dust records serve as valuable palaeoclimatic indicators for studying atmospheric variability across different temporal scales. In this study, we employed Haar fluctuations to analyse global spatiotemporal atmospheric variability over the Last Glacial Cycle, capturing both high- and low-frequency information within the records, regardless of uniform or non-uniform sampling. Furthermore, we utilised Haar fluctuations to compute fluctuation correlations, thereby enhancing our understanding of palaeoclimate dynamics.Our findings reveal a latitudinal dependency in the transition from macroweather to climate regimes (tau c), with polar regions experiencing shorter transitions compared to the tropics and mid-latitudes. These transitions occur at approximately 1/100th of glacial cycle length scales, suggesting a dominant forcing mechanism beyond Milankovitch cycles. Additionally, our analysis shows that polar regions have larger fluctuation amplitudes than lower latitudes as a consequence of the polar amplification effect. Furthermore, fluctuation correlations demonstrate faster synchronisation between the poles themselves compared to lower-latitude sites, achieving high correlation values within 10 kyr.Therefore, our findings suggest a consistent climate signal propagating from the poles to the Equator, representing the first empirical evidence supporting the hypothesis that the poles play a pivotal role as climate change drivers, influencing the variability in climatic transitions worldwide.

Más información

Título según WOS: Geographic variability in dust and temperature in climate scaling regimes over the Last Glacial Cycle
Título de la Revista: CLIMATE OF THE PAST
Volumen: 20
Número: 7
Editorial: Copernicus Gesellschaft mbH
Fecha de publicación: 2024
Página de inicio: 1579
Página final: 1594
DOI:

10.5194/cp-20-1579-2024

Notas: ISI