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1. Vegetation and environmental changes in tropical South America from the last glacial to the Holocene documented by multiple cave sediment proxies

   https://doi.org/10.1016/j.epsl.2019.115717  

   Novello, Valdir F. ; Cruz, Francisco W. ; McGlue, Michael M. ; Wong, Corinne I. ; Ward, Brittany M. ; Vuille, Mathias ; Santos, Rudney A. ; Jaqueto, Plinio ; Pessenda, Luiz C.R. ; Atorre, Tiago ; et al ( October 2019 , Earth and Planetary Science Letters)
2. Atmospheric methane variability through the Last Glacial Maximum and deglaciation mainly controlled by tropical sources

   https://doi.org/10.1038/s41561-023-01332-x  

   Riddell-Young, Ben ; Rosen, Julia ; Brook, Edward ; Buizert, Christo ; Martin, Kaden ; Lee, James ; Edwards, Jon ; Mühl, Michaela ; Schmitt, Jochen ; Fischer, Hubertus ; et al ( December 2023 , Nature Geoscience)
3. Tropical Cyclones Downscaled from Simulations of the Last Glacial Maximum

   https://doi.org/10.1175/JCLI-D-20-0409.1  

   Lawton, Quinton A. ; Korty, Robert L. ; Zamora, Ryan A. ( January 2021 , Journal of Climate)

   null (Ed.)

   Abstract The tracks, intensities, and other properties of tropical cyclones downscaled from three models’ simulations of the Last Glacial Maximum (LGM) are analyzed and compared to those of storms downscaled from simulations of the present climate. Globally, the mean maximum intensity of storms generated from each model is lower at LGM, as is the fraction of all storms that reach intensities of category 4 or higher on the Saffir–Simpson hurricane wind scale. The median day of the storm season shifts earlier by an average of one week in all three models in both hemispheres. Two of the three models’ LGM simulations feature a reduction in storm count and global power dissipation index compared to the current climate, but a third shows no significant difference between the two climates. Although each model is forced by the same global changes, differences in the way sea surface temperatures and other large-scale environmental conditions respond in the North Atlantic impart significant differences in the climatology at LGM between models. Our results from the cold LGM provide a novel opportunity to assess how tropical cyclones respond to climate changes. 

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4. The Spatial Distribution of Aeolian Dust and Terrigenous Fluxes in the Tropical Atlantic Ocean Since the Last Glacial Maximum

   https://doi.org/10.1029/2020PA004148  

   Rowland, George H. ; Robinson, Laura F. ; Hendry, Katharine R. ; Ng, Hong Chin ; McGee, David ; McManus, Jerry F. ( February 2021 , Paleoceanography and Paleoclimatology)

   The flux of terrestrial material from the continents to the oceans links the lithosphere, hydrosphere, and biosphere through physical and biogeochemical processes, with important implications for Earth's climate. Quantitative estimates of terrigenous fluxes from sources such as rivers, aeolian dust, and resuspended shelf sediments are required to understand how the processes delivering terrigenous material respond to and are influenced by climate. We compile thorium‐230 normalized²³²Th flux records in the tropical Atlantic to provide an improved understanding of aeolian fluxes since the Last Glacial Maximum (LGM). By identifying and isolating sites dominated by aeolian terrigenous inputs, we show that there was a persistent meridional gradient in dust fluxes in the eastern equatorial Atlantic at the LGM, arguing against a large southward shift of the intertropical convergence zone during LGM boreal winter. The ratio of LGM to late‐Holocene²³²Th fluxes highlights a meridional difference in the magnitude of variations in dust deposition, with sites <10°N showing larger changes over time. This supports an interpretation of increased trade wind strength at the LGM, potentially combined with differential changes in soil moisture and reductions in higher altitude summer winds. Our results also highlight the persistent importance of continental margins as sources of high terrigenous flux to the open ocean. This is especially evident in the western tropical Atlantic, where study locations reveal the primary influence of the South American continent up to >700 km away, characterized by²³²Th fluxes approximately twice as large as aeolian‐dominated sites in the east.

    

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5. Fingerprint of tropical climate variability and sea level in sediments of the Cariaco Basin during the last glacial period

   https://doi.org/10.1111/sed.12567  

   Deplazes, Gaudenz ; Meckler, Anna Nele ; Peterson, Larry C. ; Hamann, Yvonne ; Aeschlimann, Beat ; Günther, Detlef ; Martínez‐García, Alfredo ; Haug, Gerald H. ; Sheldon, ed., Nathan ( February 2019 , Sedimentology)

   High‐resolution palaeorecords of climate are critical to improving current understanding of climate variability, its sensitivity and impact on the environment in the past and in the future. Sediments from the Cariaco Basin off the coast of Venezuela have proven to be sensitive recorders of tropical palaeoclimate variability down to an annual scale. However, the fingerprint of climate and sea level in the sediments of the last glacial period is still not completely understood. In this study, lamination analysis of sediments from the Cariaco Basin is extended to the last glacial period. Detailed sedimentological and geochemical analysis (laser ablation–inductively coupled plasma–mass spectrometry) reveals couplets of light‐coloured, terrigenous‐rich and dark‐coloured, biogenic opal‐rich laminae, which are interpreted to reflect the seasonal migration of the Intertropical Convergence Zone. In addition, a previously undescribed, nearly pure terrigenous lamina type is observed, which is referred to hereafter as a ‘C‐layer’. The C‐layers in the sedimentary sequence are interpreted as flood layers that originate from local rivers. The occurrence of these C‐layers is investigated for two core locations in the Cariaco Basin over the last 110 kyr by continuous X‐ray fluorescence scanning. Dansgaard–Oeschger oscillations are most clearly traced by proxies reflecting productivity and marine organic matter content of the sediment. In contrast, the abundance of terrigenous material differs at times between the two sites. On an interglacial to glacial timescale, the ability to record events causing C‐layers is likely to be influenced by changes in sea level and source proximity. On a millennial scale, both sediment cores contain more C‐layers during warmer interstadials compared with colder stadials during Marine Isotope Stage 3. This finding implies that interstadials were not only wetter than stadials, but probably also characterized by increased rainfall variability, leading to an enhanced frequency of flooding events in the hinterland of the Cariaco Basin.

    

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