Understanding climate variability and stability under extremely warm 'greenhouse' conditions in the past is essential for future climate predictions. However, information on millennial-scale (and shorter) climate variability during such periods is scarce, owing to a lack of suitable high-resolution, deep-time archives. Here we present a continuous record of decadal- to orbital-scale continental climate variability from annually laminated lacustrine deposits formed during the late Early Cretaceous (123-120 Ma: late Barremian-early Aptian) in southeastern Mongolia. Inter-annual changes in lake algal productivity for a 1091-year interval reveal a pronounced solar influence on decadal- to centennial-scale climatic variations (including the ~ 11-year Schwabe cycle). Decadally-resolved Ca/Ti ratios (proxy for evaporation/precipitation changes) for a ~ 355-kyr long interval further indicate millennial-scale (~ 1000-2000-yr) extreme drought events in inner-continental areas of mid-latitude palaeo-Asia during the Cretaceous. Millennial-scale oscillations in Ca/Ti ratio show distinct amplitude modulation (AM) induced by the precession, obliquity and short eccentricity cycles. Similar millennial-scale AM by Milankovitch cycle band was also previously observed in the abrupt climatic oscillations (known as Dansgaard-Oeschger events) in the 'intermediate glacial' state of the late Pleistocene, and in their potential analogues in the Jurassic 'greenhouse'. Our findings indicate that external solar activity forcing was effective on decadal-centennial timescales, whilst the millennial-scale variations were likely amplified by internal process such as changes in deep-water formation strength, even during the Cretaceous 'greenhouse' period.
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http://dx.doi.org/10.1038/s41598-022-25815-w | DOI Listing |
Sci Total Environ
December 2024
Centro de Investigación Esquel de Montaña y Estepa Patagónica (CIEMEP; CONICET-UNPSJB), Roca 780, Esquel, Chubut CA 9200, Argentina; Facultad de Ciencias Naturales y Ciencias de la Salud, Universidad Nacional de la Patagonia San Juan Bosco, Esquel, Chubut CA 9200, Argentina. Electronic address:
Plastic pollution has garnered much more attention in marine environments, while scientific research on freshwater and terrestrial ecosystems has been relatively overlooked. Numerous studies worldwide have highlighted the presence of macroplastics (>2.5 cm) in mountain riverine environments, revealing that even these seemingly pristine ecosystems are not invulnerable to plastic contamination.
View Article and Find Full Text PDFEcotoxicol Environ Saf
December 2024
Aquatic Contaminants Research Division, Environment and Climate Change Canada, Montréal, Québec, Canada. Electronic address:
The Hydra vulgaris bioassay is recognized as sensitive invertebrate test species for toxicity assessment of real-life environmental mixtures for enforcement and monitoring investigations. The purpose of this study was to characterize the intra-laboratory variability, study the influence of environmental variables (temperature, luminosity, inter-individual and day of analysis) on ZnSO toxicity, a reference model toxicant for hydra. The sublethal (effect concentration for 50 % of hydra-EC50) and lethal (lethal concentration for 50 % of hydra-LC50) were determined based on characteristic morphological changes for this species.
View Article and Find Full Text PDFAmbio
December 2024
Department of Building Engineering, Energy Systems and Sustainability Science, University of Gävle, Kungsbärcksvägen 47, SE-801 76, Gävle, Sweden.
This study aims to expand the understanding of public acceptance of carbon taxes by exploring the role of habits. Habits play a pivotal role in guiding our behaviors and reasoning and can even influence our self perception and identity but remain an underexplored variable in relation to public policy acceptance. We employed a large scale (N > 5200) national survey to measure public acceptance of higher carbon taxation in Sweden, also capturing car driving habits, car usage, and other relevant variables.
View Article and Find Full Text PDFPorcine Health Manag
December 2024
Animal Nutrition and Feed Science Laboratory, Department of Animal Science and Technology, Sunchon National University, Suncheon, 57922, Republic of Korea.
Background: Respiratory disease is an economically important disease in the swine industry. Housing air quality control is crucial for maintaining the respiratory health of pigs. However, maintaining air quality is a limitation of current housing systems.
View Article and Find Full Text PDFEnviron Monit Assess
December 2024
General Dynamics Information Technology, U.S. Environmental Protection Agency, Narragansett, RI, USA.
Estuaries have been adversely impacted by increased nutrient loads. Eutrophication impacts from these loads include excess algal blooms and low oxygen conditions. In this study, we leveraged data from 28 monitoring programs in the northeastern US to explore the relationships between eutrophication response variables and watershed and estuarine variables.
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