Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung

A standardized permafrost ground temperature collection for Canada 2025

Abstract. Ground temperature is an essential variable for monitoring the thermal state of permafrost, developing models, and conducting fundamental research. However, the usability of GT data in Canada is often hampered by inconsistent file formats, a lack of metadata standardiza...

Dynamic nutrient competition (de-)stabilizes photosymbiosis

ABSTRACT Photosymbioses between heterotrophic hosts and phototrophic symbionts are critical to productivity in oligotrophic aquatic ecosystems. The ecological success of this relationship is rooted in the efficient metabolic exchange between symbiotic partners, yet this nutrition...

Avian cholera causes mass mortality at penguin mega-colonies amid H5N1 HPAI outbreaks in Antarctica

The characterization of pathogens affecting Antarctic wildlife has been historically limited and sporadic. With the introduction of H5N1 high pathogenicity avian influenza virus (HPAIV) in Antarctica in the austral summer 2023/2024, concerns about the health of Antarctic seabirds...

Cretaceous–Palaeogene Plate Boundary Evolution at the Pacific Margins of Zealandia and West Antarctica

Improved satellite‐derived gravity data support updated interpretations and models of ancient plate boundaries and plate motions affecting Zealandia and West Antarctica. The models combine to confidently resolve hundreds of kilometres of Late Cretaceous–Eocene motion between the...

Investigation into the transforming mechanism from flash-to-conventional drought in different soil moisture layers in a highly climate-diverse basin

Study region The Indus Basin, a highly diverse climate basin in South Asia. Study focus The transformation from flash drought to conventional drought (FD-CD) poses significant challenges to drought risk and management systems, necessitating a comprehensive assessment of the dynam...

Linking marine benthic biodiversity and ecosystem functions related to carbon cycling in a continental mud depocenter

Abstract. The importance of carbon storage in continental seafloor sediments is increasingly recognized, yet the role of benthic macrofaunal biodiversity in the regulation of these processes remains poorly understood. Benthic macrofauna contributes to organic carbon cycling throu...

Episodic isolation of the Arctic Mediterranean from the North Atlantic during late Pleistocene glacials

Abstract It has been proposed that the Arctic Ocean and Nordic Seas (together referred to as the “Arctic Mediterranean” - AM) were not only covered by a thick ice shelf during past Pleistocene glaciations 1 but also filled with freshwater 2 implying a disconnection from the North...

Antarctic sea ice response to meltwater due to Antarctic ice sheet mass loss in a multi-model ensemble

Abstract. We present the first multi-model study of the Antarctic sea ice response to enhanced meltwater due to dynamic mass loss from the Antarctic ice sheet. This meltwater flux (and its future increase under global warming) is not included in the most recent state-of-the-art c...

Impact of grid resolution on the abyssal ocean representation in numerical models

Accurately representing abyssal water masses and their inter-basin pathways remains a challenge for global ocean models and reanalyses. In this study, we investigate how horizontal and vertical resolution influence the simulation of abyssal waters by first evaluating three ocean...

Quantifying aggregation bias in marsh carbon flux estimates caused by rhizosphere oxygen heterogeneity

Oxygen (O 2 ) in marsh rhizospheres varies strongly at millimetre scales due to radial oxygen loss (ROL), re-oxidation of reduced compounds, hydrology, and sediment structure. Yet many models estimate heterotrophic (microbial) respiration at a single mean O 2 , which can bias CO...

Climate Knowledge in Large Language Models

Abstract Large language models (LLMs) are increasingly deployed for climate-related applications, where understanding internal climatological knowledge is important for assessing their reliability. Despite growing adoption, the capacity of LLMs to recall climate normals from para...

Variability of internal snow properties over Antarctic late summer sea ice on different spatial scales

Snow on Antarctic sea ice strongly affects thermodynamic processes, sea ice mass balance, and microwave remote sensing, yet its spatial variability and characteristic length scales remain poorly quantified. The aim of this study is to provide a spatially extensive, layer-resolved...

A Survey and Comparison of Ocean Biogeochemistry Models in the natESM Initiative

This paper presents a comprehensive survey of contemporary ocean biogeochemistry (OBGC) models within the natESM (National Earth System Modeling) initiative, conducted by the natESM Ocean Biogeochemistry Working Group. We systematically document nine OBGC models spanning diverse...

Spring phytoplankton bloom dynamics reveal thresholds of ocean alkalinity enhancement in the North Sea

Abstract Spring phytoplankton blooms drive primary production and food web dynamics in marine ecosystems. Ocean alkalinity enhancement, a proposed carbon dioxide removal strategy, alters seawater chemistry and could disrupt planktonic food webs, yet its ecological consequences re...

Freshwater‐Induced Surface Cooling of the Subpolar North Atlantic in a Large‐Ensemble, High‐Resolution, Coupled Model

Abstract As a gateway between the Arctic and subtropics, the subpolar North Atlantic plays a key role in large‐scale climate variability. In recent decades, the region has experienced pronounced freshening. While much attention has been paid to the expected long‐term weakening of...

C-PEAT's Global Peatland Carbon Database (v.2025)

Abstract. Field-based measurements are foundational to the study of short- and long-term peatland carbon dynamics. For decades, the scientific community has amassed hundreds of valuable empirical datasets in the form of peat core records from around the world. Those records typic...

Complexity promotes stability in mutualistic networks through weaker mutualistic dependencies: Insights from Generalized Modelling

Abstract Mutualistic networks provide essential contributions to long‐term ecosystem functioning and food security, but Anthropocene stressors continue to alter their structure and size. Previous theoretical approaches produce conflicting predictions for how network features infl...

Resistance of Icelandic lake ecosystems to two centuries of agricultural pressures despite growing instability

Abstract In the early nineteenth century, Iceland entered the global market, which caused a large expansion and modernisation of agricultural practices, including rising livestock numbers, higher crop density and the introduction of artificial fertilizers and pesticides. However,...

Organic carbon pathways across the fluvial-marine transition zone of the Mackenzie River Delta – Beaufort Sea region and implications on ocean color remote sensing

Abstract. Arctic warming and hydrological intensification are accelerating permafrost thaw and increasing the export of terrestrial organic carbon (OC) and sediments from land via rivers and shallow coastal waters into marine waters, yet the fate of these materials in deltaic and...

Greenland's Topography Triggers Cyclogenesis: Synergy Between Lee Cyclogenesis and Jet Streak

Abstract Arctic cyclones play a crucial role in shaping Arctic weather patterns and influencing sea ice concentrations. During the Multidisciplinary Drifting Observatory for the Study of Arctic Climate expedition in April 2020, an Arctic cyclone was observed at the leeside of Gre...