[{"content":" Leo Saffin Researcher in cyclones of tropical origin #I am a postdoc at the University of Reading. My research interests are focused on the dynamics of the atmosphere, how it is affected by small-scale and diabatic processes, and how these processes are represented in models. My current work is investigating the interaction between tropical-origin cyclones and midlatitude dynamics\nI have previously worked on:\nEddy feedbacks in climate models and the connection to the signal-to-noise paradox The dynamics of trade-wind cumulus clouds and their representation in kilometre-scale and convection-parametrizing models Reduced-precision computing for parametrizations The influences of diabatic processes on large-scale dynamics in the midlatitudes and their relation to forecast errors See the projects page for more details.\n","date":null,"permalink":"https://leosaffin.github.io/","section":"","summary":"","title":""},{"content":"","date":null,"permalink":"https://leosaffin.github.io/projects/","section":"","summary":"","title":""},{"content":"Project webpage #","date":"2023-01-08","permalink":"https://leosaffin.github.io/projects/huracan/","section":"","summary":"Cyclones of tropical origin that impact Europe, and increasing risks due to climate change","title":"Huracan"},{"content":"Project webpage #","date":"2023-01-04","permalink":"https://leosaffin.github.io/projects/constrain/","section":"","summary":"Eddy feedbacks and the signal-to-noise paradox in climate models","title":"CONSTRAIN"},{"content":"Project webpage #","date":"2020-01-01","permalink":"https://leosaffin.github.io/projects/eurec4a/","section":"","summary":"Field campaign studying trade-wind cumulus clouds","title":"EUREC\u003csup\u003e4\u003c/sup\u003eA"},{"content":"Project webpage #","date":"2020-01-01","permalink":"https://leosaffin.github.io/projects/paracon/","section":"","summary":"Improving the representation of convection across model scales","title":"ParaCon"},{"content":"","date":"2017-01-10","permalink":"https://leosaffin.github.io/projects/ithaca/","section":"","summary":"Reduced-precision computing for weather and climate models","title":"ITHACA"},{"content":"Project webpage #","date":"2017-01-09","permalink":"https://leosaffin.github.io/projects/nawdex/","section":"","summary":"The impact of diabatic processes on the jet stream and downstream influences","title":"NAWDEX"},{"content":"","date":"2013-01-09","permalink":"https://leosaffin.github.io/projects/phd/","section":"","summary":"Using potential vorticity tracers to investigate the influence of diabatic processes on large-scale dynamics and model errors","title":"PhD"},{"content":"","date":null,"permalink":"https://leosaffin.github.io/categories/","section":"Categories","summary":"","title":"Categories"},{"content":" 2026 #An improved approach to identifying tropical cyclones in model data using the cyclone phase space: warm core, symmetric, and intensifying Leo Saffin, Kevin Hodges, Stella Bourdin, Michael Fiorino, John Methven, Pier Luigi Vidale, and Alexander J Baker Monthly Weather Review, Submitted\nA synoptic overview of the EUREC\\(^4\\)A field campaign Leo Saffin, Richard Jones, Juliane Schwendike, Arlene Laing, Kathy-Ann Caesar and etc. Quarterly Journal of the Royal Meteorological Society, In Review\n2025 # HuracanPy: A Python package for reading and analysing cyclone tracks Stella Bourdin and Leo Saffin\nJournal of Open Source Software PDF 2024 # Large Uncertainties When Diagnosing the “Eddy Feedback Parameter” and Its Role in the Signal-To-Noise Paradox Leo Saffin, Christine M. McKenna, Rémy Bonnet, and Amanda C. Maycock\nGeophysical Research Letters PDF 2023 # Kilometer-Scale Simulations of Trade-Wind Cumulus Capture Processes of Mesoscale Organization Leo Saffin, Adrian Lock, Lorenzo Tomassini, Alan Blyth, Steven Böing, Leif Denby, and John Marsham\nJournal of Advances in Modeling Earth Systems PDF 2022 # Climate Modeling in Low Precision: Effects of Both Deterministic and Stochastic Rounding E. Adam Paxton, Matthew Chantry, Milan Klöwer, Leo Saffin, and Tim Palmer\nJournal of Climate\n2021 # Circulation conservation in the outflow of warm conveyor belts and consequences for Rossby wave evolution Leo Saffin, John Methven, Jake Bland, Ben Harvey, and Claudio Sanchez\nQuarterly Journal of the Royal Meteorological Society PDF EUREC\\(^4\\)A Bjorn Stevens, Sandrine Bony, David Farrell, Felix Ament, Alan Blyth, Christopher Fairall, Johannes Karstensen, Patricia K. Quinn, Sabrina Speich, and etc.\nEarth System Science Data \\\n2020 # Reduced‐precision parametrization: lessons from an intermediate‐complexity atmospheric model Leo Saffin, Sam Hatfield, Peter Düben, and Tim Palmer\nQuarterly Journal of the Royal Meteorological Society PDF 2017 # Processes Maintaining Tropopause Sharpness in Numerical Models Leo Saffin, Suzanne L. Gray, John Methven, and Keith D. Williams\nJournal of Geophysical Research: Atmospheres PDF Linking weather forecast errors with the processes responsible Leo Saffin PhD Thesis PDF 2016 # The non‐conservation of potential vorticity by a dynamical core compared with the effects of parametrized physical processes Leo Saffin, John Methven, and Suzanne L. Gray\nQuarterly Journal of the Royal Meteorological Society PDF ","date":null,"permalink":"https://leosaffin.github.io/publications/","section":"Publications","summary":"","title":"Publications"},{"content":" Highlights My Repositories Contributions Repositories For Papers Private Repositories Highlights # HuracanPy #A python package for working with various forms of feature tracking data, including but not restricted to cyclone tracks. Developed with Stella Bourdin as part of the huracan project to unify and improve how we work with tropical cyclone tracks.\nMy Repositories # iris-extensions #Most of the data analysis I do is in some way built on iris. This is a library I have built up from various things I have done using iris.\npylagranto #This is a modified version of the Lagranto tool for calculating Lagrangian trajectories. I changed it so that I could calculate trajectories using model level data from the Met Office\u0026rsquo;s Unified Model. It is essentially the same Fortran code for calculating trajectories but the main loop and reading data has been replaced with python code, so it is more flexible and easier to modify.\npygame-plot #A very simple plotting interface that I use to quickly browse through gridded data using the arrow keys and allows me to use matplotlib colour scales.\nleosaffin.github.io #The repository for this website. Based on alshedivat/al-folio\nContributions # twin-otter #A library of useful scripts for analysing and visualising data from the twin-otter aircraft which was part of the EUREC4A field campaign.\neurec4a-environment #A library of functions and scripts for calculating variables that describe the large-scale environment from observation taken during the EUREC4A field campaign\nflight-phase-separation #YAML files describing the flights and flight segements during the EUREC4A field campaign. I generated the files for the twinotter flights here. They are not in the main repository yet because the data files are not openly available, so the automated testing required to put them in the main repository can\u0026rsquo;t be done yet.\nspeedy.f90 #This is Sam Hatfield\u0026rsquo;s version of the SPEEDY model using more modern Fortran code. I used his older version for my work on reduced-precision computing in parametrizations, but this is in a private repository. I did help fix some issues with porting from Fortran77 to Fortran90 that made their way into this public repository as well though.\nRepositories for papers # constrain and eddy-feedback #Library for current work with code to calculate dynamical indices (e.g. eddy-feedbacks, North Atlantic Oscillation). I\u0026rsquo;m using CMIP6 and ERA5 data, but it should work for any gridded data. The eddy-feedback repository has the more specific code for making data and figures for \u0026ldquo;Large Uncertainties When Diagnosing the \u0026lsquo;Eddy Feedback Parameter\u0026rsquo; and Its Role in the Signal-To-Noise Paradox\u0026rdquo;\nmoisture-tracers #Code used to produce results and figures in \u0026ldquo;Kilometer-Scale Simulations of Trade-Wind Cumulus Capture Processes of Mesoscale Organization\u0026rdquo;\nwcb-outflow #Code used to produce results and figures in \u0026ldquo;Circulation conservation in the outflow of warm conveyor belts and consequences for Rossby wave evolution\u0026rdquo;\nPrivate Repositories # Diabatic tracers in the UM # During my PhD I worked a lot with potential vorticity (PV) and potential temperature (\\(\\theta\\)) tracers. These tracers work by accumulating the tendencies in these variables from each parametrization at each timestep and advecting them as tracers. Because PV and \\(\\theta\\) are conserved by advection, each tracer gives the accumulated change in PV or \\(\\theta\\) due to a specific physical process over the course of a model run and a tracer of the initial field completes the budget. Initially I worked on a branch taken from Jeff Changnon. The tracers and my developments were then taken by Claudio Sanchez and fully incorparated in to the UM so that they are now available for anyone using the UM with minimal effort.\nI have also more recently worked with moisture tracers, the same idea but for specific humidity, which are not included in the main UM, but I have branches for versions 12.0 and 12.2.\nStandalone CoMorph #CoMorph is a new convection parametrization in development at the Met Office. As part of my work on the ParaCon project, I took the standalone version of CoMorph and added an interface for using netCDF files so that I could run it from EUREC4A observations.\n","date":null,"permalink":"https://leosaffin.github.io/software/","section":"","summary":"Code I have worked on","title":"Software"},{"content":"","date":null,"permalink":"https://leosaffin.github.io/tags/","section":"Tags","summary":"","title":"Tags"}]