skip to content

The Godwin Laboratory for Palaeoclimate Research

 

Wed 28 May 13:00: Title to be confirmed

http://talks.cam.ac.uk/show/rss/15125 - Mon, 12/05/2025 - 16:28
Title to be confirmed

Abstract not available

Add to your calendar or Include in your list

Wed 14 May 14:00: Explainability can foster trust in artificial intelligence in geoscience and disaster risk management

http://talks.cam.ac.uk/show/rss/15125 - Thu, 08/05/2025 - 14:40
Explainability can foster trust in artificial intelligence in geoscience and disaster risk management

Artificial Intelligence (AI) is transforming many fields, including geosciences and disaster risk management, by offering powerful tools for analysing complex systems and supporting critical decision-making process. However, as the complexity and potentially the predictive skill of an AI model increases, its interpretability — the ability to understand the model and its predictions from a physical perspective — may decrease. In critical situations, such as scenarios caused by natural hazards, the resulting lack of understanding of how a model works and consequent lack of trust in its results can become a barrier to its implementation.

This talk focuses on the emerging field of Explainable AI (XAI), which enhances the human-comprehensible understanding and interpretation of opaque ‘black-box’ AI models, can build trust in AI model results, and encourage greater adoption of AI methods in geoscience and disaster risk management. Drawing on recent research, it highlights how XAI can enhance the adoption of AI in this field and outlines key challenges, current trends, and promising directions for future integration of XAI into geoscience and disaster risk management applications.

Add to your calendar or Include in your list

Mon 12 May 13:00: Title to be confirmed

http://talks.cam.ac.uk/show/rss/15125 - Wed, 07/05/2025 - 12:48
Title to be confirmed

Abstract not available

Add to your calendar or Include in your list

Wed 28 May 14:00: Seismic Constraints on the Temperature and Composition of Earth's Interior: Some Open Questions

http://talks.cam.ac.uk/show/rss/15125 - Wed, 07/05/2025 - 12:03
Seismic Constraints on the Temperature and Composition of Earth's Interior: Some Open Questions

Despite major advances in the quantity and quality of seismic data, several first-order questions about the thermal and compositional structure of the Earth’s interior remain unresolved. This is due in part to the uncertain relationship between seismic velocities and physical properties such as temperature and composition, but more critically, to the limited resolving power of seismic observations and the lack of a clear physical meaning of seismic models.

In this talk, I will review several efforts made over the years to address two fundamental questions through an interdisciplinary approach: a) Is the Earth’s mantle well-mixed, and to what extent? b) What do we know about the bulk composition, thermal state (and thickness) of the continental lithosphere?

The first question will involve a review of seismic constraints on the spherically averaged structure of the Earth’s mantle, focusing on current insights into thermal and compositional variations with depth. Given the complexity of this topic, I will highlight select studies and findings from my past research that help illuminate these issues, while leaving open areas of ongoing debate and uncertainty.

For addressing the second question, I will focus on recent advancements in imaging the continental lithosphere, with a particular focus on the crustal portion. I will discuss techniques such as ambient noise analysis to measure the dispersion and attenuation of short-period surface waves, along with receiver function analysis, to refine our understanding of the composition and thermal state of the lithosphere. Finally, I will explore efforts to develop thermochemical models of the Earth’s crust that align with these seismic observations.

Add to your calendar or Include in your list

Thu 15 May 11:30: Vertical mixing and associated biogeochemical fluxes via radium isotopes

http://talks.cam.ac.uk/show/rss/15125 - Wed, 07/05/2025 - 10:37
Vertical mixing and associated biogeochemical fluxes via radium isotopes

The coastal ocean is a highly dynamic and vital biogeochemical mediator between land and sea. Coastal waters frequently experience poor water quality derived from land-based anthropogenic pressure, which is often attributed to surface water sources, such as rivers. Subsurface sources (e.g., submarine groundwater discharge, benthic fluxes), however, often rival or exceed river contributions to coastal water and chemical budgets. Yet subsurface sources are understudied because they are challenging to quantify.

In this talk, I will first give a broad overview on quantifying subsurface flows using U-Th series geochemical tracers (radium, radon). Then I will present an ecosystem-scale study across the Baltic Sea, where we used 224Ra to quantify vertical mixing across a largely hypoxic deep water column. We collected radium and solute (e.g., dissolved silicate) bottom water profiles from 50 stations along a ~5000 km cruise track in the Baltic Sea. 224Ra-derived vertical mixing rates were on the order of 10-4 m2/s, well-within range of previous local-scale estimates based on modeling and sediment core incubations. Diffusive solute fluxes were also similar in magnitude to previous studies. Overall, this talk will highlight an innovative method for quantifying diffusive fluxes and contextualize findings in terms of broader biogeochemical significance.

Add to your calendar or Include in your list

Wed 07 May 17:30: Detecting reversible retreat and readvance of the Antarctic Ice Sheet during the Holocene

http://talks.cam.ac.uk/show/rss/17246 - Mon, 05/05/2025 - 12:35
Detecting reversible retreat and readvance of the Antarctic Ice Sheet during the Holocene

Several lines of geological evidence from both the marine and terrestrial record tell us that the Antarctic Ice Sheet was much bigger than present at the Last Glacial Maximum. Determining how it has changed in both thickness and extent since then, in particular whether it has undergone any major fluctuations in the last few thousand years, is important for validating ice sheet and glacial-isostatic adjustment models that are used to project future sea level rise.

In this talk, I will present an overview of the emerging evidence for large-scale reversible retreat of the Antarctic Ice Sheet during the mid to late Holocene period. I will discuss the methods with which we can further investigate this phenomenon and present a case study from the Amundsen Sea sector illustrating how cosmogenic nuclide measurements in subglacial bedrock reveal regrowth of the Pine Island-Thwaites Glacier system from a smaller than present configuration in the Holocene. Direct evidence for reversible retreat from this and other locations in Antarctica is urgently needed in order to understand what drives regrowth of ice sheets in warm climates and the conditions under which ongoing retreat could be reversed.

Add to your calendar or Include in your list

Wed 07 May 17:30: Detecting reversible retreat and readvance of the Antarctic Ice Sheet during the Holocene

http://talks.cam.ac.uk/show/rss/15125 - Mon, 05/05/2025 - 12:35
Detecting reversible retreat and readvance of the Antarctic Ice Sheet during the Holocene

Several lines of geological evidence from both the marine and terrestrial record tell us that the Antarctic Ice Sheet was much bigger than present at the Last Glacial Maximum. Determining how it has changed in both thickness and extent since then, in particular whether it has undergone any major fluctuations in the last few thousand years, is important for validating ice sheet and glacial-isostatic adjustment models that are used to project future sea level rise.

In this talk, I will present an overview of the emerging evidence for large-scale reversible retreat of the Antarctic Ice Sheet during the mid to late Holocene period. I will discuss the methods with which we can further investigate this phenomenon and present a case study from the Amundsen Sea sector illustrating how cosmogenic nuclide measurements in subglacial bedrock reveal regrowth of the Pine Island-Thwaites Glacier system from a smaller than present configuration in the Holocene. Direct evidence for reversible retreat from this and other locations in Antarctica is urgently needed in order to understand what drives regrowth of ice sheets in warm climates and the conditions under which ongoing retreat could be reversed.

Add to your calendar or Include in your list

Wed 04 Jun 17:30: Island timelines to quantify biodiversity change

http://talks.cam.ac.uk/show/rss/17246 - Mon, 05/05/2025 - 12:00
Island timelines to quantify biodiversity change

Abstract not available

Add to your calendar or Include in your list

Wed 04 Jun 17:30: Island timelines to quantify biodiversity change

http://talks.cam.ac.uk/show/rss/15125 - Mon, 05/05/2025 - 12:00
Island timelines to quantify biodiversity change

Abstract not available

Add to your calendar or Include in your list

Tue 20 May 12:00: Silica enrichment (and depletion) in the cratonic lithosphere

http://talks.cam.ac.uk/show/rss/15125 - Fri, 02/05/2025 - 10:17
Silica enrichment (and depletion) in the cratonic lithosphere

It is well established that the cratonic lithospheric mantle formed as a residue of extensive mantle melting during the Archaean. However, an unexpected feature of peridotite xenoliths from the cratonic lithosphere is that they exhibit silica contents that extend both above and below that expected after simple peridotite melting, implying a role for open system processes. High-silica peridotites, rich in orthopyroxene, are commonly found in the Kaapvaal and Siberian cratons, whereas low-silica samples, such as those from parts of Greenland and Tanzania contain anomalously high olivine. Komatiites are produced by advanced peridotite melting and predominantly erupted during the Archean, observations that appear to compliment the highly refractory nature of Archean peridotites. However, a simple melt-residue relationship is undermined by observations that both komatiite and cratonic peridotite have depleted initial Hf-isotope compositions. Using insights from petrology, thermodynamic modelling, geochemistry and high pressure experiments, this talk will investigate the conditions of silica enrichment and discuss a potential role for komatiite-peridotite interaction.

Add to your calendar or Include in your list

Wed 07 May 14:00: Searching for Long-period signals in Apollo Seismic Data

http://talks.cam.ac.uk/show/rss/15125 - Thu, 01/05/2025 - 15:15
Searching for Long-period signals in Apollo Seismic Data

Seismic data is essential for studying planetary interiors and dynamics, yet acquiring high-quality recordings in harsh extraterrestrial environments is far more challenging than on Earth. Despite being collected over five decades ago (1969-1977), the Apollo seismic data is the only available source of lunar seismic data, continuing to provide valuable insights into the Moon’s interior. When AI meets the Apollo seismic dataset, what secrets will be unlocked? Here, I present some fascinating results from applying deep learning to this legacy dataset, including the discovery of Lunar’s long-period signal, the search for the planetary free oscillation, and a tool for automatic disturbance detection and mitigation. These findings demonstrate how modern techniques can extract new knowledge from historic recordings, opening a new window into understanding planetary interiors and revolutionising our approach to lunar seismology.

Add to your calendar or Include in your list

Wed 18 Jun 17:30: Rock magnetic estimation of past precipitation from topsoil calibration - recent studies in Europe and India

http://talks.cam.ac.uk/show/rss/17246 - Wed, 30/04/2025 - 13:21
Rock magnetic estimation of past precipitation from topsoil calibration - recent studies in Europe and India

Several rock magnetic parameters have been demonstrated to be related to climate. The concept behind magnetic enhancement is that during soil formation, specific iron minerals are formed depending on soil properties, which depend on amongst others precipitation and temperature. In the mid-latitudes, mainly magnetite and maghemite are formed, and these minerals represent a proxy for ‘soil formation intensity’ in some regions, which is driven by i.a. precipitation. While most studies focus on Eurasian Chernozems due to their rather simple stratigraphy and formation processes, other soil types such as luvisols also show elevated magnetic properties in topsoils in relation to climate.

In this presentation, I will provide a short overview of the concept of using magnetic proxies for (paleo)climate studies. Further, first data from ongoing studies in Europe and India will be presented and discussed in a climate perspective. At this point magnetic properties of last interglacial soils appear clearly stronger than Holocene soil properties, suggesting a wetter than recent last interglacial.

Add to your calendar or Include in your list

Wed 18 Jun 17:30: Rock magnetic estimation of past precipitation from topsoil calibration - recent studies in Europe and India

http://talks.cam.ac.uk/show/rss/15125 - Wed, 30/04/2025 - 13:21
Rock magnetic estimation of past precipitation from topsoil calibration - recent studies in Europe and India

Several rock magnetic parameters have been demonstrated to be related to climate. The concept behind magnetic enhancement is that during soil formation, specific iron minerals are formed depending on soil properties, which depend on amongst others precipitation and temperature. In the mid-latitudes, mainly magnetite and maghemite are formed, and these minerals represent a proxy for ‘soil formation intensity’ in some regions, which is driven by i.a. precipitation. While most studies focus on Eurasian Chernozems due to their rather simple stratigraphy and formation processes, other soil types such as luvisols also show elevated magnetic properties in topsoils in relation to climate.

In this presentation, I will provide a short overview of the concept of using magnetic proxies for (paleo)climate studies. Further, first data from ongoing studies in Europe and India will be presented and discussed in a climate perspective. At this point magnetic properties of last interglacial soils appear clearly stronger than Holocene soil properties, suggesting a wetter than recent last interglacial.

Add to your calendar or Include in your list

Wed 07 May 17:30: Detecting reversible retreat and readvance of the Antarctic Ice Sheet during the Holocene

http://talks.cam.ac.uk/show/rss/17246 - Wed, 30/04/2025 - 12:38
Detecting reversible retreat and readvance of the Antarctic Ice Sheet during the Holocene

Several lines of geological evidence from both the marine and terrestrial record tell us that the Antarctic Ice Sheet was much bigger than present at the Last Glacial Maximum. Determining how it has changed in both thickness and extent since then, in particular whether it has undergone any major fluctuations in the last few thousand years, is important for validating ice sheet and glacial-isostatic adjustment models that are used to project future sea level rise.

In this talk, I will present an overview of the emerging evidence for large-scale reversible retreat of the Antarctic Ice Sheet during the mid to late Holocene period. I will discuss the methods with which we can further investigate this phenomenon and present a case study from the Amundsen Sea sector illustrating how cosmogenic nuclide measurements in subglacial bedrock reveal regrowth of the Pine Island-Thwaites Glacier system from a smaller than present configuration in the Holocene. Direct evidence for reversible retreat from this and other locations in Antarctica is urgently needed in order to understand what drives regrowth of ice sheets in warm climates and the conditions under which ongoing retreat could be reversed.

Add to your calendar or Include in your list