LARA: a Lagrangian Reanalysis based on ERA5 spanning from 1940 to 2023

Lucie Bakels; Michael Blaschek; Marina Dütsch; Andreas Plach; Vincent Lechner; Georg Brack; Leopold Haimberger; Andreas Stohl

doi:10.5194/essd-17-4569-2025

journal article Open Access Sep 18, 2025

LARA: a Lagrangian Reanalysis based on ERA5 spanning from 1940 to 2023

Lucie Bakels

Michael Blaschek Marina Dütsch

Andreas Plach

Vincent Lechner Georg Brack Leopold Haimberger

Andreas Stohl

Earth System Science Data Vol. 17 No. 9 pp. 4569-4585 · Copernicus GmbH

View at Publisher Save 10.5194/essd-17-4569-2025

Abstract

Abstract. Meteorological reanalyses are crucial datasets in atmospheric research, providing the foundation for many scientific applications. However, most reanalyses follow a Eulerian framework, providing data at specific, fixed points in space and time. This fixed-location approach is suitable for many scientific analyses, but studies focused on transport in the atmosphere would benefit from a Lagrangian framework, which provides data along dynamic, continuous trajectories following the movement of air. To achieve this, the Lagrangian particle dispersion model FLEXPART was driven offline with data from ECMWF’s (European Centre for Medium-Range Weather Forecasts) latest reanalysis, ERA5, to convert the Eulerian ERA5 data into a Lagrangian format. FLEXPART utilises the grid-scale winds from ERA5 and stochastic parameterisations of turbulence and convection to advect particles in a domain-filling mode, where the global atmosphere is represented by 6 million particles that move freely in the atmosphere, with their number density following closely the density of air. The resulting new Lagrangian Reanalysis (LARA: https://doi.org/10.5281/zenodo.14639472, Bakels, 2025) dataset has been stored in an easily searchable database and made accessible to researchers all over the world. It will enable a wide range of studies, including global and regional analyses of extreme events, water and energy transport in the atmosphere, and atmospheric energy budgets. Here, we describe the data format and how the data can be accessed and analysed. Using four examples, we give a non-exhaustive list of possible applications for which LARA could be used for. We show methods for how the evolution of air masses and their properties can be studied and how climatologies can be established. Our examples include a study of the evolution of the Hadley cell circulation, a climatology of warm conveyor belt events, a measure of continentality based on the time it takes for air to reach land from the ocean, and an evaluation of the dynamical consistency between subsequent ERA5 meteorological fields.

Topics

No keywords indexed for this article. Browse by subject →

References

65

[1]

Arnold, D., Maurer, C., Wotawa, G., Draxler, R., Saito, K., and Seibert, P.: Influence of the meteorological input on the atmospheric transport modelling with FLEXPART of radionuclides from the Fukushima Daiichi nuclear accident, J. Environ. Radioact., 139, 212–225, https://doi.org/10.1016/j.jenvrad.2014.02.013, 2015. a 10.1016/j.jenvrad.2014.02.013

[2]

Baier, K., Duetsch, M., Mayer, M., Bakels, L., Haimberger, L., and Stohl, A.: The Role of Atmospheric Transport for El Niño-Southern Oscillation Teleconnections, Geophys. Res. Lett., 49, e2022GL100906, https://doi.org/10.1029/2022GL100906, 2022. a 10.1029/2022gl100906

[3]

Bakels, L.: LARA analysis data, Zenodo [data set], https://doi.org/10.5281/zenodo.14639472, 2025. a, b

[4]

FLEXPART version 11: improved accuracy, efficiency, and flexibility

Lucie Bakels, Daria Tatsii, Anne Tipka et al.

Geoscientific Model Development 10.5194/gmd-17-7595-2024

[5]

Bakels, L., Blaschek, M., Dütsch, M., Plach, A., Lechner, V., Brack, G., Haimberger, L., and Stohl, A.: LARA: a Lagrangian Reanalysis based on ERA5 spanning from 1940 to 2023, PHAIDRA [data set], https://phaidra.univie.ac.at/o:2121554 (last access: 25 August 2025), 2025. a, b, c 10.5194/essd-2025-26

[6]

High-resolution (1 km) Köppen-Geiger maps for 1901–2099 based on constrained CMIP6 projections

Hylke E. Beck, Tim R. McVicar, Noemi Vergopolan et al.

Scientific Data 10.1038/s41597-023-02549-6

[7]

The ERA5 global reanalysis: Preliminary extension to 1950

Bill Bell, Hans Hersbach, Adrian Simmons et al.

Quarterly Journal of the Royal Meteorological Soci... 10.1002/qj.4174

[8]

Cassiani, M., Stohl, A., and Brioude, J.: Lagrangian stochastic modelling of dispersion in the convective boundary layer with skewed turbulence conditions and a vertical density gradient: Formulation and implementation in the FLEXPART model, Bound.-Lay. Meteorol., 154, 367–390, https://doi.org/10.1007/s10546-014-9976-5, 2015. a 10.1007/s10546-014-9976-5

[9]

Chen, B., Xu, X.-D., Yang, S., and Zhang, W.: On the origin and destination of atmospheric moisture and air mass over the Tibetan Plateau, Theor. Appl. Climatol., 110, 423–435, https://doi.org/10.1007/s00704-012-0641-y, 2012. a 10.1007/s00704-012-0641-y

[10]

Courtier, P. and Talagrand, O.: Variational Assimilation of Meteorological Observations With the Adjoint Vorticity Equation. Ii: Numerical Results, Q. J. Roy. Meteor. Soc., 113, 1329–1347, https://doi.org/10.1002/qj.49711347813, 1987. a 10.1256/smsqj.47812

[11]

Dirmeyer, P. A. and Brubaker, K. L.: Contrasting evaporative moisture sources during the drought of 1988 and the flood of 1993, J. Geophys. Res.-Atmos., 104, 19383–19397, https://doi.org/10.1029/1999JD900222, 1999. a 10.1029/1999jd900222

[12]

Eckhardt, S., Stohl, A., Wernli, H., James, P., Forster, C., and Spichtinger, N.: A 15-Year Climatology of Warm Conveyor Belts, J. Climate, 17, 218–237, https://doi.org/10.1175/1520-0442(2004)017&lt;0218:AYCOWC&gt;2.0.CO;2, 2004. a, b, c, d, e, f, g 10.1175/1520-0442(2004)017<0218:aycowc>2.0.co;2

[13]

The Atlantic Multidecadal Oscillation and its relation to rainfall and river flows in the continental U.S.

David B. Enfield, Alberto M. Mestas‐Nuñez, Paul J. Trimble

Geophysical Research Letters 10.1029/2000gl012745

[14]

Flaounas, E., Kotroni, V., Lagouvardos, K., Gray, S. L., Rysman, J.-F., and Claud, C.: Heavy rainfall in Mediterranean cyclones. Part I: contribution of deep convection and warm conveyor belt, Clim. Dynam., 50, 2935–2949, https://doi.org/10.1007/s00382-017-3783-x, 2018. a 10.1007/s00382-017-3783-x

[15]

Fremme, A. and Sodemann, H.: The role of land and ocean evaporation on the variability of precipitation in the Yangtze River valley, Hydrol. Earth Syst. Sci., 23, 2525–2540, https://doi.org/10.5194/hess-23-2525-2019, 2019. a 10.5194/hess-23-2525-2019

[16]

Fujiwara, M., Wright, J. S., Manney, G. L., Gray, L. J., Anstey, J., Birner, T., Davis, S., Gerber, E. P., Harvey, V. L., Hegglin, M. I., Homeyer, C. R., Knox, J. A., Krüger, K., Lambert, A., Long, C. S., Martineau, P., Molod, A., Monge-Sanz, B. M., Santee, M. L., Tegtmeier, S., Chabrillat, S., Tan, D. G. H., Jackson, D. R., Polavarapu, S., Compo, G. P., Dragani, R., Ebisuzaki, W., Harada, Y., Kobayashi, C., McCarty, W., Onogi, K., Pawson, S., Simmons, A., Wargan, K., Whitaker, J. S., and Zou, C.-Z.: Introduction to the SPARC Reanalysis Intercomparison Project (S-RIP) and overview of the reanalysis systems, Atmos. Chem. Phys., 17, 1417–1452, https://doi.org/10.5194/acp-17-1417-2017, 2017. a 10.5194/acp-17-1417-2017

[17]

The Modern-Era Retrospective Analysis for Research and Applications, Version 2 (MERRA-2)

Ronald Gelaro, Will McCarty, Max J. Suárez et al.

Journal of Climate 10.1175/jcli-d-16-0758.1

[18]

Gimeno, L., Drumond, A., Nieto, R., Trigo, R. M., and Stohl, A.: On the origin of continental precipitation, Geophys. Res. Lett., 37, L13804, https://doi.org/10.1029/2010GL043712, 2010. a 10.1029/2010gl043712

[19]

Grise, K. M. and Davis, S. M.: Hadley cell expansion in CMIP6 models, Atmos. Chem. Phys., 20, 5249–5268, https://doi.org/10.5194/acp-20-5249-2020, 2020. a, b 10.5194/acp-20-5249-2020

[20]

Hakim, G. J., Emile-Geay, J., Steig, E. J., Noone, D., Anderson, D. M., Tardif, R., Steiger, N., and Perkins, W. A.: The last millennium climate reanalysis project: Framework and first results, J. Geophys. Res.-Atmos., 121, 6745–6764, https://doi.org/10.1002/2016JD024751, 2016. a 10.1002/2016jd024751

[21]

Array programming with NumPy

Charles R. Harris, K. Jarrod Millman, Stéfan J. van der Walt et al.

Nature 10.1038/s41586-020-2649-2

[22]

Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Muñoz-Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D., Simmons, A., Soci, C., Abdalla, S., Abellan, X., Balsamo, G., Bechtold, P., Biavati, G., Bidlot, J., Bonavita, M., De Chiara, G., Dahlgren, P., Dee, D., Diamantakis, M., Dragani, R., Flemming, J., Forbes, R., Fuentes, M., Geer, A., Haimberger, L., Healy, S., Hogan, R. J., Hólm, E., Janisková, M., Keeley, S., Laloyaux, P., Lopez, P., Lupu, C., Radnoti, G., de Rosnay, P., Rozum, I., Vamborg, F., Villaume, S., and Thépaut, J.-N.: The ERA5 global reanalysis, Q. J. Roy. Meteor. Soc., 146, 1999–2049, https://doi.org/10.1002/qj.3803, 2020. a, b, c, d 10.1002/qj.3803

[23]

xarray: N-D labeled Arrays and Datasets in Python

Stephan Hoyer, Joe Hamman

Journal of Open Research Software 10.5334/jors.148

[24]

Hu, Y., Huang, H., and Zhou, C.: Widening and weakening of the Hadley circulation under global warming, Sci. Bull., 63, 640–644, https://doi.org/10.1016/j.scib.2018.04.020, 2018. a 10.1016/j.scib.2018.04.020

[25]

Matplotlib: A 2D Graphics Environment

John D. Hunter

Computing in Science & Engineering 10.1109/mcse.2007.55

[26]

The JRA-55 Reanalysis: General Specifications and Basic Characteristics

Shinya KOBAYASHI, Yukinari OTA, Yayoi HARADA et al.

Journal of the Meteorological Society of Japan. Se... 10.2151/jmsj.2015-001

[27]

Kosaka, Y., Kobayashi, S., Harada, Y., Kobayashi, C., Naoe, H., Yoshimoto, K., Harada, M., Goto, N., Chiba, J., Miyaoka, K., Sekiguchi, R., Deushi, M., Kamahori, H., Nakaegawa, T., Tanaka, T. Y., Tokuhiro, T., Sato, Y., Matsushita, Y., And Onogi, K.: The JRA-3Q Reanalysis, J. Meteor. Soc. Jpn. Ser. II, 102, 49–109, https://doi.org/10.2151/jmsj.2024-004, 2024. a 10.2151/jmsj.2024-004

[28]

Köppen, W.: Versuch einer Klassifikation der Klimate, vorzugsweise nach ihren Beziehungen zur Pflanzenwelt, Geogr. Z., 6, 593–611, http://www.jstor.org/stable/27803924 (last access: 25 August 2025), 1900. a

[29]

Läderach, A. and Sodemann, H.: A revised picture of the atmospheric moisture residence time, Geophys. Res. Lett., 43, 924–933, 2016. a 10.1002/2015gl067449

[30]

Madonna, E., Wernli, H., Joos, H., and Martius, O.: Warm Conveyor Belts in the ERA-Interim Dataset (1979–2010). Part I: Climatology and Potential Vorticity Evolution, J. Climate, 27, 3–26, https://doi.org/10.1175/JCLI-D-12-00720.1, 2014. a, b, c, d, e 10.1175/jcli-d-12-00720.1

[31]

Met Office: Cartopy: a cartographic python library with a Matplotlib interface, Met Office [software], Exeter, Devon, https://scitools.org.uk/cartopy (last access: 25 August 2025), 2010–2015. a

[32]

Nieto, R., Gimeno, L., and Trigo, R. M.: A Lagrangian identification of major sources of Sahel moisture, Geophys. Res. Lett., 33, L18707, https://doi.org/10.1029/2006GL027232, 2006. a 10.1029/2006gl027232

[33]

Petterssen, S.: Weather analysis and forecasting: a textbook on synoptic meteorology, McGraw-Hill Book Company, 1940. a

[34]

Pisso, I., Sollum, E., Grythe, H., Kristiansen, N. I., Cassiani, M., Eckhardt, S., Arnold, D., Morton, D., Thompson, R. L., Groot Zwaaftink, C. D., Evangeliou, N., Sodemann, H., Haimberger, L., Henne, S., Brunner, D., Burkhart, J. F., Fouilloux, A., Brioude, J., Philipp, A., Seibert, P., and Stohl, A.: The Lagrangian particle dispersion model FLEXPART version 10.4, Geosci. Model Dev., 12, 4955–4997, https://doi.org/10.5194/gmd-12-4955-2019, 2019. a, b, c 10.5194/gmd-12-4955-2019

[35]

Reithmeier, C. and Sausen, R.: ATTILA: atmospheric tracer transport in a Lagrangian model, Tellus B, 54, 278–299, https://doi.org/10.3402/tellusb.v54i3.16666, 2002. a 10.1034/j.1600-0889.2002.01236.x

[36]

Rienecker, M. M., Suarez, M. J., Gelaro, R., Todling, R., Bacmeister, J., Liu, E., Bosilovich, M. G., Schubert, S. D., Takacs, L., Kim, G.-K., Bloom, S., Chen, J., Collins, D., Conaty, A., da Silva, A., Gu, W., Joiner, J., Koster, R. D., Lucchesi, R., Molod, A., Owens, T., Pawson, S., Pegion, P., Redder, C. R., Reichle, R., Robertson, F. R., Ruddick, A. G., Sienkiewicz, M., and Woollen, J.: MERRA: NASA's Modern-Era Retrospective Analysis for Research and Applications, J. Climate, 24, 3624–3648, https://doi.org/10.1175/JCLI-D-11-00015.1, 2011. a 10.1175/jcli-d-11-00015.1

[37]

The NCEP Climate Forecast System Reanalysis

Suranjana Saha, Shrinivas Moorthi, Hua-Lu Pan et al.

Bulletin of the American Meteorological Society 10.1175/2010bams3001.1

[38]

Soci, C., Hersbach, H., Simmons, A., Poli, P., Bell, B., Berrisford, P., Horányi, A., Muñoz-Sabater, J., Nicolas, J., Radu, R., Schepers, D., Villaume, S., Haimberger, L., Woollen, J., Buontempo, C., and Thépaut, J.-N.: The ERA5 global reanalysis from 1940 to 2022, Q. J. Roy. Meteor. Soc., 150, 764, 4014–4048, https://doi.org/10.1002/qj.4803, 2024. a, b 10.1002/qj.4803

[39]

Sodemann, H., Schwierz, C., and Wernli, H.: Interannual variability of Greenland winter precipitation sources: Lagrangian moisture diagnostic and North Atlantic Oscillation influence, J. Geophys. Res.-Atmos., 113, D03107, https://doi.org/10.1029/2007JD008503, 2008. a, b 10.1029/2007jd008503

[40]

Sprenger, M. and Wernli, H.: A northern hemispheric climatology of cross-tropopause exchange for the ERA15 time period (1979–1993), J. Geophys. Res.-Atmos., 108, 8521, https://doi.org/10.1029/2002JD002636, 2003. a 10.1029/2002jd002636

[41]

Stachnik, J. P. and Schumacher, C.: A comparison of the Hadley circulation in modern reanalyses, J. Geophys. Res.-Atmos., 116, D22102, https://doi.org/10.1029/2011JD016677, 2011. a 10.1029/2011jd016677

[42]

Sterl, A.: On the (In)Homogeneity of Reanalysis Products, J. Climate, 17, 3866–3873, https://doi.org/10.1175/1520-0442(2004)017&lt;3866:OTIORP&gt;2.0.CO;2, 2004. a 10.1175/1520-0442(2004)017<3866:otiorp>2.0.co;2

[43]

Stohl, A.: Computation, accuracy and applications of trajectories – A review and bibliography, Atmos. Environ., 32, 947–966, https://doi.org/10.1016/S1352-2310(97)00457-3, 1998. a 10.1016/s1352-2310(97)00457-3

[44]

Stohl, A.: A 1-year Lagrangian “climatology” of airstreams in the northern hemisphere troposphere and lowermost stratosphere, J. Geophys. Res.-Atmos., 106, 7263–7279, https://doi.org/10.1029/2000JD900570, 2001. a, b 10.1029/2000jd900570

[45]

Stohl, A. and James, P.: A Lagrangian analysis of the atmospheric branch of the global water cycle. Part I: Method description, validation, and demonstration for the August 2002 flooding in central Europe, J. Hydrometeorol., 5, 656–678, https://doi.org/10.1175/1525-7541(2004)005&lt;0656:ALAOTA&gt;2.0.CO;2, 2004. a 10.1175/1525-7541(2004)005<0656:alaota>2.0.co;2

[46]

A Lagrangian Analysis of the Atmospheric Branch of the Global Water Cycle. Part II: Moisture Transports between Earth’s Ocean Basins and River Catchments

Andreas Stohl, Paul James

Journal of Hydrometeorology 10.1175/jhm470.1

[47]

Stohl, A. and Koffi, N’dri E.: Evaluation of trajectories calculated from ECMWF data against constant volume balloon flights during ETEX, Atmos. Environ., 32, 4151–4156, https://doi.org/10.1016/S1352-2310(98)00185-X, 1998. a 10.1016/s1352-2310(98)00185-x

[48]

Stohl, A., Hittenberger, M., and Wotawa, G.: Validation of the Lagrangian particle dispersion model FLEXPART against large-scale tracer experiment data, Atmos. Environ., 32, 4245–4264, https://doi.org/10.1016/S1352-2310(98)00184-8, 1998. a, b 10.1016/s1352-2310(98)00184-8

[49]

Stohl, A., Eckhardt, S., Forster, C., James, P., and Spichtinger, N.: On the pathways and timescales of intercontinental air pollution transport, J. Geophys. Res.-Atmos., 107, ACH 6-1–ACH 6-17, https://doi.org/10.1029/2001JD001396, 2002. a 10.1029/2001jd001396

[50]

Stohl, A., Wernli, H., James, P., Bourqui, M., Forster, C., Liniger, M. A., Seibert, P., and Sprenger, M.: A New Perspective of Stratosphere–Troposphere Exchange, B. Am. Meteorol. Soc., 84, 1565–1574, https://doi.org/10.1175/BAMS-84-11-1565, 2003. a 10.1175/bams-84-11-1565

Showing 50 of 65 references

Metrics

1

Citations

65

References

Details

Published: Sep 18, 2025
Vol/Issue: 17(9)
Pages: 4569-4585
License: View

Authors

Department of Meteorology and Geophysics, University of Vienna, Vienna, Austria

A

Andreas Stohl

Funding

Austrian Science Fund Award: P 34170-N

Cite This Article

Lucie Bakels, Michael Blaschek, Marina Dütsch, et al. (2025). LARA: a Lagrangian Reanalysis based on ERA5 spanning from 1940 to 2023. Earth System Science Data, 17(9), 4569-4585. https://doi.org/10.5194/essd-17-4569-2025

LARA: a Lagrangian Reanalysis based on ERA5 spanning from 1940 to 2023

You May Also Like