[This dataset is embargoed until January 4, 2027]. This dataset includes results obtained from lake sediments across sites in the Indian (N = 6) and Bangladeshi (N = 10) Ganges Brahmaputra Meghna, Vietnamese Mekong (N = 4) and Vietnamese Red River (N = 7) Deltas for grain-size, total inorganic/organic carbon, XRF, magnetic susceptibility, core scan imaging, sedimentary pigments, stable isotopes, radiometric dating (chronological), and site data including water chemistry at the time that sediment cores were obtained from 2022 to 2023. Data are generated across multiple cores taken from each site at a differing range of depth resolutions within the sediment cores. Each dataset contains values that have measured a specific proxy (pigments, grain-size, etc.) that help reconstruct environmental change of physico-chemical and biological components over time. Each dataset type for a specific site will have been measured from cores taken from the same site. Each dataset present for the region it covers (Bangladesh, India, Red River, Mekong) represents the total amount of data obtained for that region. However, not all sites studied within the region will have data represented in each dataset as time, funds, and quality of sediment core precluded the use of some analyses for those sites. Full details about this dataset can be found at https://doi.org/10.5285/96e0e308-440d-4a93-a32e-2e454382b65a
