Results 31 to 40 of about 531 (138)

Estimation of gas record alteration in very low-accumulation ice cores [PDF]

Climate of the Past, 2020
We measured the methane mixing ratios of enclosed air in five ice core sections drilled on the East Antarctic Plateau. Our work aims to study two effects that alter the recorded gas concentrations in ice cores: layered gas trapping artifacts and firn ...
K. Fourteau, P. Martinerie, X. Faïn, A. A. Ekaykin, J. Chappellaz, V. Lipenkov   +5 more
doaj   +1 more source

Dynamic time warping to quantify age distortion in firn cores impacted by melt processes

Annals of Glaciology, 2023
As warming intensifies across the Greenland ice sheet, an increasing number of shallow coring and radar studies are targeting the melt-impacted firn column to investigate meltwater processes.
Cedric J. Hagen, Joel T. Harper
doaj   +1 more source

Learning to melt: Emulating Greenland surface melt from a polar RCM with machine learning [PDF]

The Cryosphere
Predicting surface melt on the Greenland ice sheet is critical for understanding surface mass balance (SMB) and its sensitivity to a changing climate. Polar regional climate models (RCMs) are the primary tools for simulating melt and projecting future ...
E. Schlager, E. Schlager, S. Scher, R. H. Mottram, P. L. Langen   +4 more
doaj   +1 more source

Critical porosity of gas enclosure in polar firn independent of climate [PDF]

Climate of the Past, 2017
In order to interpret the paleoclimatic record stored in the air enclosed in polar ice cores, it is crucial to understand the fundamental lock-in process.
C. F. Schaller, J. Freitag, O. Eisen, O. Eisen   +3 more
doaj   +1 more source

Triple Oxygen Isotope Compositions of Isotopic Reference Waters: Implications for VSMOW‐Scale and VSMOW–SLAP‐Scale Δ′17O Calibration

Geostandards and Geoanalytical Research, EarlyView.
Key Points Triple oxygen isotope ratios of two primary (VSMOW, SLAP) and twelve secondary water isotopic reference materials were precisely measured using BrF5 fluorination‐IRMS. The measured Δ'17OVSMOW value for SLAP (34 ± 6 per meg) demonstrates that VSMOW‐SLAP normalisation ensures interlaboratory comparability, but introduces systematic offsets for
Ryoji Tanaka, Andreas Pack, Tyler B. Coplen   +2 more
wiley   +1 more source

Passive Radar Sounding for Firn Aquifer Monitoring

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Firn aquifers may play an important role in the mass balance of the Greenland ice sheet, but changes in their water storage are challenging to measure due to their spatiotemporal variability.
Sean T. Peters, Angela Wang, Riley Culberg   +2 more
doaj   +1 more source

A Gain‐of‐Function Mutation in DELLA Selectively Alters Protein Interactions to Regulate Wheat Tiller Angle and Plant Height

Plant Biotechnology Journal, EarlyView.
ABSTRACT Plant architecture, especially plant height and tiller angle, plays a pivotal role in determining wheat yield. In this study, we characterize a wheat mutant termed prostrate and semidwarf 1 (prose1), exhibiting both a prostrate growth habit and semidwarfism.
Chaoqun Dong, Dejie Du, Yingying Li, Siyao Jia, Zhe Zhang, Yiqing Wang, Shuai Zheng, Xincheng Wang, Mingming Xin, Yingyin Yao, Lingling Chai, Zhongfu Ni, Qixin Sun, Jie Liu   +13 more
wiley   +1 more source

Finite Viscoelastic Modeling of Ice Shelves Using Glen's Flow Law and Depth‐Dependent Material Properties

Proceedings in Applied Mathematics and Mechanics, Volume 26, Issue 4, December 2026.
ABSTRACT Ice shelves are floating seaward extensions of glaciers that form where land‐based ice flows into the ocean. Recent observations suggest that their mechanical behavior is suitably described by a viscoelastic Maxwell model, as this framework captures both the instantaneous elastic response and the time‐dependent viscous flow of ice.
Marvin Koßler, Sebastian Skatulla, Angelika Humbert, Ralf Müller, Jörg Schröder   +4 more
wiley   +1 more source

Challenges in modeling the energy balance and melt in the percolation zone of the Greenland ice sheet

Journal of Glaciology, 2023
Increased surface melt in the percolation zone of the Greenland ice sheet causes significant changes in the firn structure, directly affecting the amount and timing of meltwater runoff.
Federico Covi, Regine Hock, Carleen H. Reijmer   +2 more
doaj   +1 more source

Interpreting Air Temperature Trends Across the Antarctic Peninsula Between 1979 and 2025

Geophysical Research Letters, Volume 53, Issue 20, 28 October 2026.
Abstract The near‐surface temperature of the Antarctic Peninsula is marked by strong spatio‐temporal variability. In situ observations are scarce and therefore have limited spatial coverage. Furthermore, ERA‐5 reanalysis does not have a sufficient spatial resolution to capture the steep topography and other climate gradients of the peninsula.
Koen van der Aa, Carleen Reijmer, Peter Kuipers Munneke, Michiel van den Broeke   +3 more
wiley   +1 more source