Scientific drilling in the ocean and on continents provides unique window into the workings of the interior of our planet, Earth surface processes, paleoclimates, natural hazards and the distribution of subsurface microbial life. The past and current scientific drilling programs of the International Ocean Discovery Program (IODP), the International Ocean Drilling Programme (IODP3) and the International Continental Scientific Drilling Program (ICDP) continue to foster major advances in many interdisciplinary fields of socio-economic relevance, such as climate and ecosystem evolution, palaeoceanography, the deep biosphere, sustainable georesources, crustal and tectonic processes, geodynamics and geohazards. This session invites contributions that present and/or review recent scientific results from deep Earth sampling and monitoring through ocean and continental drilling projects. Furthermore, we encourage contributions outlining visions for future drilling projects, as well as new research emerging from scientific drilling legacy data.

This Inter- and Transdisciplinary Session will critically re-examine outstanding questions and long-standing paradigms in Earth system science in the context of global climate. Earth system science has developed around the idea of dynamic interactions among atmosphere, hydrosphere, biosphere, geosphere, and cryosphere, through flows of energy, material, and information.
Scientific progress helps us identify which of these flows are most important in different contexts, and the rules and processes —physical, biological, chemical, and ecological—that govern them. Over time, established ideas can be confirmed, challenged, or reshaped by new evidence, leading to gradual shifts or even step changes in understanding. To give some examples across disciplines and spatial-temporal scales:
- The understanding of clouds and their role in the Earth system is rapidly evolving, with major recent advances in mapping out and characterizing the properties of atmospheric aerosol particles and their interactions with clouds.
- The latest high-resolution climate simulations, built on decades on climate modelling, expose previously overlooked complexities in ocean-atmosphere coupling, revealing how fine-scale interactions can affect weather extremes.
- Soil organic matter was once conceptualized as chemically defined compartments with fixed turnover times, a view later revised to emphasize the role of physical protection mechanisms in controlling carbon and nutrient cycling.
- A century-old paradigm of vertical crustal stacking beneath the Himalayan-Tibetan orogen has been challenged by new geodynamical simulations revealing the Asian mantle as an active uplift mechanism and structural support for the region’s topography.
This session invites contributions that revisit and reflect on the foundational literature that has shaped our current understanding of Earth system science. We welcome critical engagement with influential frameworks or seminal papers —whether by questioning, expanding, or reinterpreting them in the light of recent advances. The aim is to explore how scientific knowledge evolves over time and how earlier ideas have informed this evolution and continue to affect or challenge present-day thinking.

Biogeomorphology provides an integrative perspective to study two-way interactions between organisms and landforms, linking ecological processes with erosion, transport, and deposition processes. This integrative lens shows how biotic–abiotic feedbacks shape Earth surface dynamics and landscape patterns across multiple spatial and temporal scales - from single plants to catchments and from events to millennia. Recent advances in biogeomorphic understanding have expanded applications across alpine, fluvial, coastal, and aeolian systems, for example in nature-based solutions. Key concepts such as biogeomorphic succession provide shared ground for cross-system comparison.

Despite a growing number of studies, biogeomorphology is still an emerging field with the conceptual and empirical foundation being under active development. In addition, transferring scientific knowledge of biogeomorphic feedbacks into management-relevant knowledge remains an ongoing challenge. With this session, we aim to advance the conceptual foundation of biogeomorphology and foster its transfer into practice. Contributions may range from alpine and polar environments over riverine landscapes to lowland and coastal systems, highlighting the relevance of biogeomorphology for improving process understanding and informing sustainable management strategies.

We invite contributions spanning fundamental process research, experimental, field-based and remote sensing studies, as well as applied approaches to environmental management and natural hazard mitigation. We particularly encourage work that uses biogeomorphology as a lens to address pressing geoscientific challenges, including ecosystem–landform feedbacks, human impacts on biogeomorphic systems, and the integration of multi-scale observations and models. Contributions from early career scientists are particularly welcome.

The atmosphere and cryosphere are closely linked and should be studied as an interdisciplinary subject. Most cryospheric regions have undergone significant changes in recent decades, as these areas are particularly fragile and less adaptable to global climate change. This AS-CR session invites both modeling- and observation-based studies on all aspects of the interactions between atmospheric processes and snow and ice, at local, regional, and global scales. Special emphasis is placed on the Arctic and Antarctic regions, high latitudes and altitudes, mountainous areas, sea ice, and permafrost regions.
In particular, we encourage studies that investigate the role of aerosols—such as black carbon, organic carbon, dust, volcanic ash, microplastics, pollen, sea salt, diatoms, bioaerosols, bacteria, and others—and their effects on the cryosphere, including snow/ice melt and albedo changes. The session also focuses on dust transport, aeolian deposition, and volcanic dust, with consideration of their health, environmental, and climate impacts in high-latitude, high-altitude, and cold polar regions. We welcome contributions from biological and ecological sciences, including studies on dust-organism interactions, cryoconites, bio-albedo, eco-physiological processes, biogeochemical cycles, and genomic analyses. Related topics include light-absorbing impurities, cold deserts, dust storms, long-range transport, glacier darkening, polar ecology, and more. Improved scientific understanding of atmosphere–cryosphere interactions is essential and should be better integrated into global climate prediction scenarios.

Soils are interdisciplinary materials, characterized by geological, (micro)biological, biogeochemical, hydrological, and geophysical processes, which take place from the surface down to bedrock. Only by considering these processes down the whole soil profile can we fully anticipate how soils will respond to global change. Research into the spatial and temporal variability of properties from the surface to bedrock, as well as the implications on environment and ecosystem interactions, is crucial for advancing our understanding of the whole soil system.

This interdisciplinary session invites contributions that investigate properties, functions, and services down the whole soil profile. Topics may include (but are not limited to):

1. Mapping and characterising soil thickness and structure using geophysical, geospatial, and field-based approaches.
2. Deep soil biology and geobiology, revealing the distribution of microbial communities and processes, particularly across the soil-bedrock continuum.
3. Biogeochemical cycling, mineral weathering, and nutrient availability with depth.
4. Carbon stocks and stabilisation across soil and bedrock, and the role that subsoil geochemical environments play in carbon dynamics.
5. Hydrological processes through the soil profile, interactions with groundwater and surface waters, and issues of deep soil contamination.

We encourage contributions from a wide range of EGU Divisions, including but not limited to Soil System Sciences, Biogeosciences, Energy Resources and the Environment, Geochemistry Mineralogy Petrology and Volcanology, and Hydrological Sciences. This session aims to inspire cross-disciplinary approaches to understand soil systems as central to Earth’s future.

Fluids are an important agent in almost all geologic processes that shape marine geology. Spatial and temporal variations in fluid flow activity modify total fluxes between geo-, cryo-, hydro-, and atmosphere. The natural release of fluids at the seafloor is called seepage, and the corresponding sites are called cold seeps when fluids are expelled at seawater temperature. Natural seepage is mainly associated with elevated greenhouse gases such as methane and carbon dioxide, which can alter the biogeochemical cycles at the seafloor. Cold seeps are characterized by high CH4 and shallow sulphate-methane transition zone in the sediment and lead lead to enhanced benthic anoxia and increased ocean acidification. Released greenhouse gases can directly escape into the water column, potentially reaching to the atmosphere. The release of fluids from subseafloor sediments also poses a major geohazard by decreasing the stability of slopes, fuelling mud volcanoes, or causing massive blowouts. At the same time, the release of methane and associated fluids may enhance primary production ( ‘oases of life’). Fluid flow linked to seepage can sustain highly diverse biological ecosystems or chemosynthetic communities on the seafloor. These habitats sustain active bacterial communities supporting anaerobic oxidation of methane (‘benthic filter’) and can buffer the released methane. However, especially in aquatic environments, a qualitative and quantitative understanding of methane cycling and fluxes across litho-, hydro- and atmospheres is contrained by the inaccessibility of offshore regions and associated difficulties in monitoring over spatial and temporal scales. This results in large uncertainties in quantifying and attributing emissions from offshore aquatic environments. Realistic estimates of aquatic methane emissions require a profound understanding of the involved fluid flow systems, including spatial and temporal variations, internal architecture, and preferential migration pathways through the overburden. Contributions may address natural fluid flow and seepage in marine or lacustrine environments across a large variety of settings. We welcome studies that integrate diverse geophysical, geochemical, biological, microbial, geological, remote sensing, numerical and laboratory approaches. Such interdisciplinary studies provide exciting opportunities to promote a better understanding of past and present fluid-driven systems in sedimentary systems.