Research

My research focuses on using numerical models and machine learning methods to better understand complex physical processes like how glaciers flow or fires spread over the landscape. Much of my work has focused on glaciology, particularly looking at how glaciers and ice sheets respond to changes in climate.

Selected publications

[1]

L. Zeller, D. McGrath, L. Sass, C. Florentine, and J. Downs, “Equilibrium line altitudes, accumulation areas and the vulnerability of glaciers in alaska,” Journal of Glaciology, vol. 71, p. e28, Jan. 2025, doi: 10.1017/jog.2024.65.

[2]

A. A. Marcozzi, J. V. Johnson, R. A. Parsons, S. J. Flanary, C. A. Seielstad, and J. Z. Downs, “Application of LiDAR derived fuel cells to wildfire modeling at laboratory scale,” Fire, vol. 6, no. 10, p. 394, Oct. 2023, doi: 10.3390/fire6100394.

[3]

J. Downs and J. V. Johnson, “A rapidly retreating, marine-terminating glacier’s modeled response to perturbations in basal traction,” Journal of Glaciology, vol. 68, no. 271, pp. 891–900, Oct. 2022, doi: 10.1017/jog.2022.5.

[4]

J. P. Briner et al., “Rate of mass loss from the greenland ice sheet will exceed holocene values this century,” Nature, vol. 586, no. 7827, pp. 70–74, Oct. 2020, doi: 10.1038/s41586-020-2742-6.

[5]

J. Z. Downs, J. V. Johnson, J. T. Harper, T. Meierbachtol, and M. A. Werder, “Dynamic hydraulic conductivity reconciles mismatch between modeled and observed winter subglacial water pressure,” Journal of Geophysical Research: Earth Surface, vol. 123, no. 4, pp. 818–836, 2018, doi: 10.1002/2017JF004522.

[6]

B. D. Fleurian et al., “SHMIP the subglacial hydrology model intercomparison project,” Journal of Glaciology, vol. 64, no. 248, pp. 897–916, Dec. 2018, doi: 10.1017/jog.2018.78.

[7]

J. Downs, D. Brinkerhoff, and M. Morlighem, “Inferring time-dependent calving dynamics at helheim glacier,” Journal of Glaciology, vol. 69, no. 274, pp. 381–396, Apr. 2023, doi: 10.1017/jog.2022.68.

[8]

J. Downs, J. Johnson, J. Briner, N. Young, A. Lesnek, and J. Cuzzone, “Western greenland ice sheet retreat history reveals elevated precipitation during the holocene thermal maximum,” The Cryosphere, vol. 14, no. 3, pp. 1121–1137, Mar. 2020, doi: 10.5194/tc-14-1121-2020.