Offshore wind in the Mediterranean: renewables can, and must, protect biodiversity – here’s how
What’s at risk for Arctic wildlife if Trump expands oil drilling in the fragile National Petroleum Reserve-Alaska
Wed 02 Jul 14:00: Rethinking Antarctic Polynya Productivity: The Impact of Ice-Adjacency Effects on NPP Estimates along Icy Coasts
Ocean color-based estimates of Antarctic net primary productivity (NPP) have indicated low nearshore productivity in ice-adjacent waters, contrasting with coupled physical-biogeochemical models. To understand this discrepancy, we assessed satellite records of polynya NPP by comparing field data with two satellite imagery datasets derived using different processing schemes. Our results indicate historical underestimation of chlorophyll a (Chl) for imagery obtained using default atmospheric correction processing within approximately 100 km of ice-covered coastlines due to adjacency effects. Using radiative transfer modeling, we find that biases in ocean color polynya observations due to adjacency effects correspond to the high albedo of ice and snow. When applying an atmospheric correction processing scheme more robust to adjacency contamination, estimates of NPP more than doubled in 65 % of polynyas, especially smaller eastern Antarctic polynyas. Adjacency effects should therefore be managed when analyzing spatial and temporal trends in Antarctic coastal primary productivity.
- Speaker: Hilde Oliver, Woods Hole Oceanographic Institution
- Wednesday 02 July 2025, 14:00-15:00
- Venue: BAS Seminar Room 1.
- Series: British Antarctic Survey - Polar Oceans seminar series; organiser: Dr Yohei Takano.
Wed 02 Jul 14:00: Rethinking Antarctic Polynya Productivity: The Impact of Ice-Adjacency Effects on NPP Estimates along Icy Coasts
Ocean color-based estimates of Antarctic net primary productivity (NPP) have indicated low nearshore productivity in ice-adjacent waters, contrasting with coupled physical-biogeochemical models. To understand this discrepancy, we assessed satellite records of polynya NPP by comparing field data with two satellite imagery datasets derived using different processing schemes. Our results indicate historical underestimation of chlorophyll a (Chl) for imagery obtained using default atmospheric correction processing within approximately 100 km of ice-covered coastlines due to adjacency effects. Using radiative transfer modeling, we find that biases in ocean color polynya observations due to adjacency effects correspond to the high albedo of ice and snow. When applying an atmospheric correction processing scheme more robust to adjacency contamination, estimates of NPP more than doubled in 65 % of polynyas, especially smaller eastern Antarctic polynyas. Adjacency effects should therefore be managed when analyzing spatial and temporal trends in Antarctic coastal primary productivity.
- Speaker: Hilde Oliver, Woods Hole Oceanographic Institution
- Wednesday 02 July 2025, 14:00-15:00
- Venue: BAS Seminar Room 1.
- Series: British Antarctic Survey - Polar Oceans seminar series; organiser: Dr Yohei Takano.
Wed 02 Jul 14:00: Rethinking Antarctic Polynya Productivity: The Impact of Ice-Adjacency Effects on NPP Estimates along Icy Coasts
Ocean color-based estimates of Antarctic net primary productivity (NPP) have indicated low nearshore productivity in ice-adjacent waters, contrasting with coupled physical-biogeochemical models. To understand this discrepancy, we assessed satellite records of polynya NPP by comparing field data with two satellite imagery datasets derived using different processing schemes. Our results indicate historical underestimation of chlorophyll a (Chl) for imagery obtained using default atmospheric correction processing within approximately 100 km of ice-covered coastlines due to adjacency effects. Using radiative transfer modeling, we find that biases in ocean color polynya observations due to adjacency effects correspond to the high albedo of ice and snow. When applying an atmospheric correction processing scheme more robust to adjacency contamination, estimates of NPP more than doubled in 65 % of polynyas, especially smaller eastern Antarctic polynyas. Adjacency effects should therefore be managed when analyzing spatial and temporal trends in Antarctic coastal primary productivity.
- Speaker: Hilde Oliver, Woods Hole Oceanographic Institution
- Wednesday 02 July 2025, 14:00-15:00
- Venue: BAS Seminar Room 1.
- Series: British Antarctic Survey - Polar Oceans seminar series; organiser: Dr Yohei Takano.
Australia’s native bees struggled after the Black Summer fires – but a world-first solution brought them buzzing back
Wed 25 Jun 14:00: Stomatal mechanics: the role of wall structure and shape in cell function
Abstract not available
- Speaker: Professor Andrew Fleming, University of Sheffield
- Wednesday 25 June 2025, 14:00-15:00
- Venue: Sainsbury Laboratory Cambridge University Auditorium - 47 Bateman Street and online (contact events@slcu.cam.ac.uk for Zoom link).
- Series: Sainsbury Laboratory Seminars; organiser: Kate Wetherell.
Wed 25 Jun 14:00: Stomatal mechanics: the role of wall structure and shape in cell function
Abstract not available
- Speaker: Professor Andrew Fleming, University of Sheffield
- Wednesday 25 June 2025, 14:00-15:00
- Venue: Sainsbury Laboratory Cambridge University Auditorium - 47 Bateman Street and online (contact events@slcu.cam.ac.uk for Zoom link).
- Series: Sainsbury Laboratory Seminars; organiser: Kate Wetherell.
Wed 25 Jun 14:00: Stomatal mechanics: the role of wall structure and shape in cell function
Abstract not available
- Speaker: Professor Andrew Fleming, University of Sheffield
- Wednesday 25 June 2025, 14:00-15:00
- Venue: Sainsbury Laboratory Cambridge University Auditorium - 47 Bateman Street and online (contact events@slcu.cam.ac.uk for Zoom link).
- Series: Sainsbury Laboratory Seminars; organiser: Kate Wetherell.
Thu 26 Jun 13:00: Statistical physics for climate sciences: applications to wave turbulence, extreme heat waves, and extremes of renewable energy production
Climate changes impacts and the need for its mitigation and adaptation will change deeply many aspects of our society. Physicists can contribute decisively to this endeavor. Indeed, the theoretical aspects of climate science are a new and highly multidisciplinary field, with contributions from statistical physics, mathematics, data and computer sciences, as well as hydrodynamics and turbulence. Research In this field are performed at the forefront of many contemporary subjects connected to statistical physics: effective dynamics, inference of stochastic processes, and inference of causality relations, and of their connection with machine learning, large deviation theory, to cite just of few examples.
In this talk I will discuss several examples where statistical physics and large deviation theory can be useful to solve fundamental problems for the dynamics of the climate system. The first example will be a theoretical contribution to the kinetic theory of wave turbulence. Wave turbulence plays an important role for atmosphere/ocean physical exchanges and for mixing of the ocean interior. I will explain how large deviation theory allows to extend this classical theory to compute effects of typical and rare spontaneous fluctuations. I will explain how this can be used for stochastic parameterization for wave energy propagation.
A large part of the talk will be dedicated to extreme heat waves. Extreme events or transitions between climate attractors are of primarily importance for understanding the impact of climate change. Recent extreme heat waves, with huge impact, are striking examples. However, they cannot be studied with conventional approaches, because they are too rare and realistic models are too complex. We will discuss several new algorithms and theoretical approaches, based on large deviation theory, rare event simulations, and machine learning for stochastic processes, which we have specifically designed for the prediction of extreme heat waves. Using the best available climate models, our approach sheds new light on the fluid mechanics processes which lead to these events. We will describe quasi-stationary patterns of turbulent Rossby waves that lead to global teleconnection patterns in connection with heat waves and analyze their dynamics.
At the end of the talk, I will briefly outline current projects where we use the same tools to study extremes of renewable energy production and their connection with climate dynamics. Those rare events are key for the future of the European electricity system
- Speaker: Freddy Bouchet, Laboratoire de Météorologie Dynamique
- Thursday 26 June 2025, 13:00-14:00
- Venue: MR13, Centre for Mathematical Sciences, Wilberforce Road, Cambridge.
- Series: DAMTP Atmosphere-Ocean Dynamics; organiser: phh1.
Jaws helped spur a fishing frenzy – so how have the world’s sharks fared since the 1975 release?
As the federal government fumbles on nature law reform, the states are forging ahead
AI helps tell snow leopards apart, improving population counts for these majestic mountain predators
Saving species starts at home: how you can help Australia’s 1,000 threatened invertebrates
A weird group of boronias puzzled botanists for decades. Now we’ve solved the pollination mystery
Wed 18 Jun 16:00: Decadal changes in Southern Ocean Water Masses inferred from observations
In this talk I will present how using a combination of data-driven and machine learning methods we infer a slowdown of Antarctic bottom water (AABW) and an expansion and poleward shift of Circumpolar Deep Water (CDW). In particular, I will present analyses based on four decades of CFCs and SF6 observations to reconstruct global tracer budgets and infer decadal variability of deep ocean circulation and tracer ventilation rates.
- Speaker: Laura Cimoli, University of Cambridge
- Wednesday 18 June 2025, 16:00-17:00
- Venue: BAS Seminar Room 1.
- Series: British Antarctic Survey - Polar Oceans seminar series; organiser: Dr Birgit Rogalla.
Wed 18 Jun 16:00: Decadal changes in Southern Ocean Water Masses inferred from observations
In this talk I will present how using a combination of data-driven and machine learning methods we infer a slowdown of Antarctic bottom water (AABW) and an expansion and poleward shift of Circumpolar Deep Water (CDW). In particular, I will present analyses based on four decades of CFCs and SF6 observations to reconstruct global tracer budgets and infer decadal variability of deep ocean circulation and tracer ventilation rates.
- Speaker: Laura Cimoli, University of Cambridge
- Wednesday 18 June 2025, 16:00-17:00
- Venue: BAS Seminar Room 1.
- Series: British Antarctic Survey - Polar Oceans seminar series; organiser: Dr Birgit Rogalla.
Wed 18 Jun 16:00: Decadal changes in Southern Ocean Water Masses inferred from observations
In this talk I will present how using a combination of data-driven and machine learning methods we infer a slowdown of Antarctic bottom water (AABW) and an expansion and poleward shift of Circumpolar Deep Water (CDW). In particular, I will present analyses based on four decades of CFCs and SF6 observations to reconstruct global tracer budgets and infer decadal variability of deep ocean circulation and tracer ventilation rates.
- Speaker: Laura Cimoli, University of Cambridge
- Wednesday 18 June 2025, 16:00-17:00
- Venue: BAS Seminar Room 1.
- Series: British Antarctic Survey - Polar Oceans seminar series; organiser: Dr Birgit Rogalla.
Wed 02 Jul 14:00: TBD
Abstract not available
- Speaker: Hilde Oliver, Woods Hole Oceanographic Institution
- Wednesday 02 July 2025, 14:00-15:00
- Venue: BAS Seminar Room 1.
- Series: British Antarctic Survey - Polar Oceans seminar series; organiser: Dr Yohei Takano.
Wed 02 Jul 14:00: TBD
Abstract not available
- Speaker: Hilde Oliver, Woods Hole Oceanographic Institution
- Wednesday 02 July 2025, 14:00-15:00
- Venue: BAS Seminar Room 1.
- Series: British Antarctic Survey - Polar Oceans seminar series; organiser: Dr Yohei Takano.