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http://dx.doi.org/10.1126/science.1129458 | DOI Listing |
Nat Commun
January 2025
Polar Terrestrial Environmental Systems, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Potsdam, Germany.
During the Pleistocene-Holocene transition, the dominant mammoth steppe ecosystem across northern Eurasia vanished, in parallel with megafauna extinctions. However, plant extinction patterns are rarely detected due to lack of identifiable fossil records. Here, we introduce a method for detection of plant taxa loss at regional (extirpation) to potentially global scale (extinction) and their causes, as determined from ancient plant DNA metabarcoding in sediment cores (sedaDNA) from lakes in Siberia and Alaska over the past 28,000 years.
View Article and Find Full Text PDFSci Total Environ
January 2025
Ministry of Earth Science, New Delhi 110003, India.
Glaciers of Jammu and Kashmir are retreating faster than those in the broader northwestern Himalayas, yet some glaciers in the Chenab River basin display signs of periodic advancement and mass gain (2005-2007). These features, such as coalescing lobate structures and blocked meltwater streams, raise intriguing questions about localized glacier dynamics. While global concerns over climate change and glacier retreat persist, the lack of detailed evidence regarding glacier advance in this region warrants further investigation.
View Article and Find Full Text PDFAstrobiology
January 2025
Department of Earth and Planetary Sciences, Birkbeck University of London, London, United Kingdom.
Eccentric planets may spend a significant portion of their orbits at large distances from their host stars, where low temperatures can cause atmospheric CO to condense out onto the surface, similar to the polar ice caps on Mars. The radiative effects on the climates of these planets throughout their orbits would depend on the wavelength-dependent albedo of surface CO ice that may accumulate at or near apoastron and vary according to the spectral energy distribution of the host star. To explore these possible effects, we incorporated a CO ice-albedo parameterization into a one-dimensional energy balance climate model.
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