The new Global Tipping Point Report warns of risks to Atlantic Ocean Circulation, but the timing remains uncertain.

We are excited to invite you to an interesting workshop on The Lofoten Basin Eddy in a Regional Context: from Physics to Ecosystem Dynamics. The workshop aims to promote the discussion on state-of-the-art research, identify key priorities, and coordinate collaborative efforts to advance our understanding of the dynamics and biogeochemistry of the LBE, and its significance for the regional ecosystems. The event will feature speakers representing initiatives such as NorSWOT, NorGlider, and the PROVOLO project. The complete agenda will follow. When: Wednesday, October 15, 9:00-13:30 Where: BCCR Lecture room, 4th floor Sign up for lunch latest by Monday, October 6: https://forms.gle/qBUetd3AZf25nrWw5 If you have already registered and are still participating, you don't need to sign up again. Best, Lucía on behalf of the LBE consortium

Hi everyone, We will have our next Stormtracks group meeting this Wednesday (15.10), from 13:00 to 14:00 at U105. This week, we will take a detour from our usual extratropical discussions for a trip to the tropics with Dandan, who will talk about the environmental factors that control tropical cyclone development. The meeting will be hybrid and you can join remotely via Zoom: https://uib.zoom.us/j/62886269543?pwd=ajWbi97zr0hbniaoQdZkUtD2EUSSri.1 Meeting ID: 628 8626 9543 | Password: qSKTfKU3 The meeting schedule for this semester is in the following google doc. https://docs.google.com/document/d/1yjicxkFp_8Y17LVftgksb1SnqSUSUXogg0pOFZfbK0g/edit?usp=sharing See you all on Wednesday! :) Cheers, ~Hari and Yangfan

Zoom: https://uib.zoom.us/j/68473038190?pwd=T3JzY0Z5UXQ4ZUdmcE56c0VrcFhhQT09 Niels Dutrievoz – “Water vapour isotopes in Antarctica as tracers of boundary layer processes and large-scale dynamics” The study of water isotopes connects two complementary fields: reconstructing past climates from ice cores and analysing the present-day Antarctic water cycle. Understanding the climatic and atmospheric drivers of isotopic signals in vapour and snow—archived in firn and ice—is key to interpreting past variability and anticipating future changes in surface mass balance. Such understanding requires models that integrate both large-scale moisture transport and air–snow exchanges. The aim of this PhD thesis is to improve our understanding of the Antarctic water cycle using isotopes as tracers of boundary-layer processes and large-scale dynamics, through a combined approach of observations and modelling with LMDZiso. First, we assess model performance over Antarctica and identify optimal configurations to minimise isotopic biases. We then investigate isotopic variability in vapour: at Concordia, East Antarctica Plateau (3233m), diurnal cycles are mainly controlled by surface fluxes, while at Dumont d’Urville, a coastal site, they result from both surface fluxes and katabatic advection. The analysis of two atmospheric river events (December 2018 and March 2022) reaching Concordia shows that isotopic variability cannot be explained by synoptic transport alone and requires a detailed representation of local boundary-layer processes. Then we investigate snow–vapour isotopic fluxes. We improve the agreement between the observed and simulated amplitudes of the diurnal cycle of vapour isotopes by introducing fractionation during sublimation and by applying the same formulation for isotopic condensation. Adding an active snow layer of about one centimetre further improves the representation of vapour isotopic anomalies during the March 2022 atmospheric river characterised by intense snowfall. All of these results provide a better understanding of the processes controlling atmospheric isotopic variability in Antarctica and improve the representation of the isotopic signal archived in snow, thereby opening promising perspectives on the interpretation of ice cores.