Mathematics and Statistics

Photo of Dr John Bruun

Dr John Bruun

Lecturer in Mathematics

 j.bruun@exeter.ac.uk

 (Streatham) 3612

 01392 723612

Overview

I’m a Physicist (Theoretical Physics, Lancaster degree: First including History minor, PhD 1994 and CPhys) and science communicator. 

I am interested in data analytics and how we can better identify and explain physical phenomena (chaotic and regular) in the climate system, especially its impact to the biosphere. I'm also a professional member of the UK and Irelands Institute of Physics (IOP), currently as member of Environmental Physics and Nonlinear and Complexity Phyics Groups and have previosly been Chair for the Physics Communicators Group and co-opted to the Women in Physics Group.  

I updated our understanding of the ENSO in 2017 & 2018 by identifying the Heartbeat of the Southern Osillation phenomena. This is a ocean-land-atmosphere coupled system. The phenomona explains the presence of low frequency modulation (multidecadal) across the Pacific basin and introduced a new method of spectral analysis to climatic science called dominant frequency state analysis (DFSA). 

The spatial wave dispersion characteristics of the Earth system are being investigated with a spatial extension to DFSA (sDFSA) developed through the Models 2 Decisions programme. This is being applied within the Isca simulation environment to help us ascertain how wave modes may alter in the context of tipping point transitions and the teleconnection characteristics that influence precipitation in Sub-Saharan Africa (Sahel) and Asia. Current work also includes extending the general extreme value process approach that I helped develop for the Northern European coastal flooding infrastructure to include climatic teleconnection.  

Overall these methods enable the identification of dynamic structure (both climatic modes and teleconnection) and extremes in a physically consistent way across observational, simulated models and paleo reconstruction records. 

Current research and science communication work themes:  

    A) ENSO teleconnection impact to food security risks in Sahel with Geography.  

    B) ENSO teleconnection and wave dispersion relationships in the Earth system as part of the Climate Science for Service Partnership         

         China (CSSP).

    C) How paleo time scale records help inform contemporary understanding of the Earth system. 

    D) Non-linear dynamic structure of Earth system modes, hysteresis and extreme value processes.

    E) Biological response characteristics in the context of physical forcing (vegetation and planktonic).  

    F) The transfer of Theoretical Physics knowledge and associated methods into climatic science. 

   G) Establishing creative and diverse ways to communicate the physics of the Earth system at both an advanced level and at an informed

        public and policy level.   

Please get in touch if you would like develop a collaboration/ PhD or Internship on any of these topics or to know more about DFSA and extreme process methods and their use.  

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Publications

Copyright Notice: Any articles made available for download are for personal use only. Any other use requires prior permission of the author and the copyright holder.

| 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 | 2014 | 2010 | 2002 | 1999 | 1994 |

2024

2023

2022

2021

2020

2019

  • Bruun JT, Evangelou SN. (2019) Anderson localization and extreme values in chaotic climate dynamics. [PDF]

2018

2017

2016

2015

2014

  • Bruun JT, Allen I, Vichi M, Somerfield P, Samuelsen A, Racault M-F, Waldron H, Monterio P, McKiver W, Bellerby R. (2014) Oceanic biogeochemical characteristic maps identified with holistic use of satellite, model and data, European Geophysical Union, Vienna, 27th Apr - 2nd May 2014, Geophysical Research Abstracts EGU2014-15766, volume 16, no. 2014.
  • Smyth TJ, Allen I, Atkinson A, Bruun JT, Harmer RA, Pingree RD, Widdicombe CE, Somerfield PJ. (2014) Ocean Net Heat Flux Influences Seasonal to Interannual Patterns of Plankton Abundance, PLoS ONE, volume 9, no. 6, pages e98709-e98709, DOI:10.1371/journal.pone.0098709. [PDF]

2010

2002

1999

1994

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