Author: Biogeomod2018

Friday 14^th November – 15:30 to 16:30 - room S.DB4.245

"Are terrestrial manganese oxides a hidden potential for critical metals ?"

by Dr. Augustin Dekoninck (Postdoc, G-Time, ULB)

 

Friday 28^th November – 15:30 to 16:30 - room S.DB4.245

"POLARIS: POLar AI Research on climate-ice Sheet interactions"

by Christof Kittel (Assistant Professor, VUB/ULiège)

 

Friday 5^th December – 15:30 to 16:30 - room S.DB4.245

"Tracing Southern Ocean biogeochemical change from million-year to centennial timescales using biomineral-bound nitrogen isotopes"

by Dr. Simone Moretti (Postdoc, Max Planck Institute for Chemistry)

 

2025-2026 IGEOS SEMINARS:

November 2025: "Afrotropical Forest Futures under Climate and Land-Use Change" by Dr Félicien Meunier (UGent)

October 2025: "How Volcano Seismology, Hydroacoustics and Pattern Recognition help us protect tourists on volcanoes and everyone’s WiFi – insights from recent case studies in the SW Pacific" by Bastian Steinke (G-Time, ULB)

October 2025: "Organo-mineral interactions in permafrost environments affected by physical degradation" by Maxime Thomas (UCLouvain)

September 2025: "Structural and Microbial Controls on Methane Seepage in Polar Regions" by Dr Maria De La Fuente Ruiz (BGEOSYS, ULB)

September 2025: "Seismology of Landslides: Insights from Irazú and Aguas Zarcas, Costa Rica" by Dr Esteban J. Chaves (OVSICORI, Universidad Nacional, Costa Rica)

Carbon fluxes from land to ocean: IPCC estimates are below reality !

A new ensemble assessment improves estimates of land-to-ocean carbon fluxes

A re-evaluation of global land-to-ocean carbon exports using a multi-model ensemble and a database of observations reveals that the export of carbon by rivers is 20% higher than that reported in the 2021 Intergovernmental Panel on Climate Change (IPCC) assessment. These findings published in Nature Geoscience underscore the important contribution of riverine carbon to the carbon budget.

Why is it important ?

Accurate estimates of the amount of carbon globally transferred from terrestrial ecosystems to oceans are needed to assess the Earth’s carbon budget and project future climate change. “Rivers make a key contribution to the land-to-ocean flux but previous estimates vary substantially, posing challenges not only for scientists attempting to reconcile the global carbon budget but also for policymakers who rely on these estimates to make informed environmental decisions” said the first author of this study, Maodian Liu, Assistant Professor at Peking University.

What was discovered ?

To obtain an improved estimate of global riverine carbon fluxes we compiled an unprecedent observational dataset of river carbon measurements containing nearly 700,000 samples. This observational dataset was then combined with modeling approaches and machine learning methods relying on state-of-the-art Earth observations to develop a novel high-resolution ensemble mean estimate, which increases the accuracy and reduce the uncertainty of carbon flux estimates. We also estimated the global carbon export from fresh groundwater to oceans based on observations, which was overlooked in previous assessments.

We found that the global riverine carbon export calculated by this framework (1 billion ton of carbon/year) is around 20% higher than that reported in the 2021 IPCC assessment. Additionally, we found that groundwater carbon export makes a minor contribution to the global carbon budget. First author Liu added “In total, our approach calculated that the current IPCC assessment underestimates the land-to-ocean carbon flux by 240 million tons of carbon per year. In addition, the different types of riverine carbon differ significantly from previous assessments".

What does it imply?

 The increased land-to-ocean carbon flux estimates obtained here suggest that oceanic CO₂ outgassing induced by river carbon discharge is more substantial than previously recognized. “Therefore, our findings reveal that the estimation of the ocean carbon sink (the uptake of fossil-fuel carbon by the ocean) as derived by millions of ocean CO2 observations is likely underestimated. Indeed, constraining the uptake of anthropogenic carbon by the ocean requires a correction for the natural CO2 outgassing induced by the river carbon route, which our study reveals is larger than reported in the last IPCC report”, said Pierre Regnier, Full Professor at the Université Libre de Brussels who conceptualized and coordinated the research (https://loac-netwk.ulb.be/) on behalf of the Global Carbon Project (https://www.globalcarbonproject.org/). Therefore, accurately quantifying land-to-ocean carbon fluxes will help to refine Earth system models of the coupled carbon cycle-climate system, improve predictions of climate change impacts, and inform more effective and targeted carbon management and mitigation strategies.

Pivotal moment for humanity as tipping point threats and opportunities accelerate

The world has reached a pivotal moment as threats from Earth system tipping points – and progress towards positive tipping points – accelerate, a new report shows.

The Global Tipping Points Report – the most comprehensive assessment of tipping points ever conducted – says humanity is currently on a disastrous trajectory.

The speed of fossil fuel phase out and growth of zero-carbon solutions will now determine the future of billions of people.

The report says current global governance is inadequate for the scale of the challenge and makes six key recommendations to change course fast, including coordinated action to trigger positive tipping points.

Link to the complete press release HERE