Alberto Carrassi

Job Position: 
Project Manager
Research Group: 
+47 467 47 817
Alberto Carrassi

Research interests

My research interests focus on the development of efficient methods to assimilate and combine data with numerical models of environmental systems. I work at the bridge between applied mathematics and geosciences and my main expertise is in dynamical systems and stochastic filtering applications to geophysics. I am interested in fundamental issues in the theory of data assimilation and in efficient methods to quantify uncertainty in high-dimensional problems such those encountered in climate science. I hold an Adjunct Associate Professor position at the Geophysical Institute of the University of Bergen (see university link).

Some specific areas of research include:

  • Assimilation in the unstable subspace
  • Treatment of model error in data assimilation
  • Ensemble Kalman filtering/smoothing 
  • Adaptive observations
  • New applications of the data assimilation: model selection, attribution of climate change, connection with machine learning  

Together with Laurent BertinoI lead the Data Assimilation group at NERSC. I currently coordinate two international projects on efficient reduced order methods for data assimilation in high-dimensional chaotic system (REDDA from the Norwegian Research Council) and on data assimilation for Lagrangian sea-ice models (DASIM I and DASIM II from the US Office of Naval Research). I am also currently invovled in other national and international projects but not as PI.

Recent publications 

The complete list of my published papers is below. 

 The papers currently under revision are:

  1. Tandeo, P., P. Alliot, M. Bocquet, A. Carrassi, T. Miyoshi, M. Pulido and Y. Zhen, 2019. Joint Estimation of Model and Observation Error Covariance Matrices in Data Assimilation: a Review. Mon. Wea. Rev. (Available here)
  2. Brajard, J., A. Carrassi, M. Bocquet and L. Bertino, 2019. Combining data assimilation and machine learning to emulate a dynamical model from sparse and noisy observations: a case study with the Lorenz 96 model. Geosci. Model Dev. Discuss. (Available here).
  3. Tondeur, M., A. Carrassi, S. Vannitsem and M. Bocquet, 2019. On the temporal scale separation in coupled data assimilation with the ensemble Kalman filter. Submitted to J. Stat. Phys.
  4. Grudzien, C., M. Bocquet and A. Carrassi, 2019. On the numerical integration of the Lorenz-96 model, with scalar additive noise, for benchmark twin experiments. Submitted to Geosci. Model Dev. Discuss. 


I am currently supervising two postdocs: Ali Aydogdu (postdoc, 2017- ) and Sukun Cheng (postdoc, 2016 - ) and co-supervising two PhD students, Francine Janneke Schevenhoven and Avneet Singh, enrolled at Geophysical Institute of the University of Bergen, and one MsC student Simon Clement from University of Grenoble (France).   

Past supervision: Colin Grudzien (postdoc, 2016-2019, now at Un. of Neveda Reno) Patrick Nima Raanes (postdoc, 2016-2018, now at NORCE), Matthias Rabatel (postdoc, 2016-2017), Maxime Tondeur (MsC student, 2016-2017, Ecole des Mines, France) and Robin Weber (MsC student, 2013-2014, Un. of Heidelberg, Germany).

News ... 

Teaching (upcoming & some past)

-- Short course "Data assimilation in the geosciences - A methodological overview". EGU 2019. Vienna, Austria, 07-12 April. 

   Co-lectured with Olivier Talagrand and Marc Bocquet. 

-- Mini Course on Data Assimilation at the upcoming school Mathematics of Climate of the London Mathematical Society. 08-12 July, Reading, UK.

   Co Lecutred with Colin Grudzien

-- Course on Data Assimilation for chaotic dynamics at the International Summer School on "Data Assimilation and its applications in oceanography, hydrology, risk&safety and reservoir engineering". Timisoara (Romania), 22nd July - 2nd August 2019

-- BsC/MsC Course on Data Assimilation at Dept. of Mathematics (University of Bergen).

   September-November 2017. Co-lectured with Geir EvensenLaurent Bertino and Patrick Raanes

   The full description of the course along with its schedule can be found here, or via the Math department webpage here.

   Exams date: 30th November and 1st December.  

Editorial and committee appointments 

Editor for Nonlinear Processes in Geophysics 

Member of scientific committee: EnKF annual workshop, EGU Session NP5.1 on Inverse problems and data assimilation in geophysics, SIAM Conference on applications of dynamical systems 

Recent and upcoming meetings, seminar and lectures  

  1. 7th International Symposium on Data Assimilation, 21-24 January 2019, Kobe, Japan
  2. Solicited talk Data Assimilation for Chaotic Geophysical Dynamics - An Overview. Session NP1.1 Mathematics of Planet Earth - EGU 2019. 10th April, 2019.

Recent lectures at international schools   

  1. Crash-Course on data assimilation: Theoretical foundation and advanced applications with focus on ensemble methods "06-09 June 2017, Bergen, Norway.
  2. "Summer School on Data Assimilation and its application in oceanography, hydrology, risk & safety and reservoir engineering", 17-28 July 2017, Sibiu, Romania. 


There are not available positions at moment, but there could be soon.

If you are interested in working with me in the DA group at NERSC as PhD or Postdoc, here are some lines of research I am currently prioritising:

  • Reduced order ensemble-based methods
  • Efficient particle filters
  • Coupled data assimilation  
  • Combination of data assimlation and machine learning

Some of them have already attached funding. For others we can explore possible sources.

Not-Science related...

 I am a certified Iyengar Yoga teacher (level: Base 2) and currently teach at yogarommet in Bergen. It would be great to meet you there !

Peer Review Publications and Books

47 total publications.