Research topics

My field of work is oriented towards the study and monitoring of our environment, including the use of remote sensing tools. In addition, I am interested in global climate change and indirectly in the physical phenomena that occur in the atmosphere. I am also developing methods for estimating, by remote sensing, the water equivalent of snow in a hydroelectric production context.


Current projects

Satellite monitoring and estimation of snow cover, snow water supply and ground temperatures Thermal and microwave infrared data fusion Development of methods for monitoring the northern environment in the context of climate change Forest fire detection Atmospheric aerosol study and air quality monitoring by remote sensing  


  • Larue F., A. Royer, D. De Sève, A. Langlois, A. Roy and L. Brucker (2017). Validation of GlobSnow-2 snow water equivalent over Eastern Canada. Remote Sensing of Environment, 194 : 264-277.
  • Derksen C., X. Xu, R.S. Dunbar, A. Colliander, Y. Kim, J. Kimball, A. Black, E. Euskirchen, A. Langlois, M. Loranty, P. Marsh, K. Rautiainen, A. Roy, A. Royer and J. Stephens (2017). Retrieving landscape freeze/thaw state from Soil Moisture Active Passive (SMAP) radar and radiometer measurements. Remote Sensing of Environment, 194 : 48–62.
  • Wigneron J.P., T.J. Jackson, P. O’Neill, G.J. De Lannoy, P. de Rosnay, J.P. Walker, P. Ferrazzoli, V. Mironov, S. Bircher, J.P. Grant, M. Kurum, M. Schwank, J. Munoz-Sabater, N. Das, A. Royer, A. Al-Yaari, A. Al Bitar, R. Fernandez-Moran, H. Lawrence, A. Mialon, M. Parrens, P. Richaume, S. Delwart and Y. Kerr (2017). Modelling the passive microwave signature from land surfaces : A review of recent results and application to the L-Band SMOS & SMAP soil moisture retrieval algorithms. Remote Sensing of Environment, Invited Review Paper, 192 : 238–262.
  • Busseau B.C., A. Royer, A. Langlois and F. Domine (2017). Analysis of snow-vegetation interactions in the Low Arctic – Subarctic transition zone (north-eastern Canada). Physical Geography, DOI: 10.1080/02723646.2017.1283477
  • Roy A., P. Toose, M. Williamson, T. Rowlandson, C. Derksen, A. Royer, A. Berg, J. Lemmetyinen and L. Arnold (2017). Response of L-Band brightness temperatures to freeze/thaw and snow dynamics in a prairie environment from ground-based radiometer measurements. Rem. Sens. of Enviro., 191 : 67-80.
  • Toose P., A. Roy, F. Solheim, C. Derksen, T. Watts, A. Royer and A. Walker (2017). Radio-frequency interference mitigating hyperspectral L-band radiometer. Geosci. Instrum. Method. Data Syst., 6 : 39–51. doi:10.5194/gi-6-39-2017.
  • Royer A., A. Roy, B. Montpetit, O. Saint-Jean-Rondeau, G. Picard, L. Brucker and A. Langlois (2017). Comparison of commonly-used microwave radiative transfer models for snow remote sensing. Remote Sensing of Environment, 190 : 247–259.
  • Roy A., A. Royer, O. St-Jean-Rondeau, B. Montpetit, G. Picard, A. Mavrovic, N. Marchand, and A. Langlois (2016) Microwave snow emission modeling uncertaintiesin boreal and subarctic environments. The Cryosphere, 10 : 623-638.
  • Papasodoro C., A. Royer, A. Langlois and E. Berthier (2016) Potential of RADARSAT-2 stereo radargrammetryfor the generation of glacier digital elevation models. J. of Glaciology, 62(233) : 486-496.
  • Roy A., A. Royer, C. Derksen, L. Brucker, A. Langlois, A. Mialon, and Y. Kerr (2015) Evaluation of Spaceborne L-band Radiometer Measurements for Terrestrial Freeze/Thaw Retrievals in Canada. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 8(9) : 4442-4459.
  • Papasodoro C., E. Berthier, A. Royer, C. Zdanowicz, and A. Langlois (2015) Area, elevation and mass changes of the two southernmost icecaps of the Canadian Arctic Archipelago between 1952 and 2014. The Cryosphere, 9 : 1535-1550.
  • André, C., Ottlé, C., Royer, A., Maignan, F. (2015). Land Surface Temperature Retrieval over circumpolar Arctic using SSM/I-SSMIS and MODIS Data.Rem. Sens. Enviro., 162 : 1-10.
  • Montpetit, B., Royer, A., Wigneron., J.-P., Chanzy, A., and Mialon, A. (2015) Evaluation of multi-frequency bare soil microwave reflectivity models. Remote Sensing of Environment, 162 : 186-195. Courtemanche, B., Montpetit, B., Royer, A., and Roy, A. (2015). Creation of a Lambertian Microwave Surface for Retrieving the Downwelling. Contribution in Ground-Based Radiometric Measurements. IEEE Geoscience and Remote Sensing Letters, 12(3).
  • Dupont F., G. Picard, A. Royer, M. Fily, A. Roy, A. Langlois and N. Champollion (2014). Modeling the microwave emission of bubbly ice : Applications to blue ice and superimposed ice in the Antarctic and Arctic. IEEE Transactions on Geoscience and Remote Sensing, 52(10) : 6639-6651.
  • Langlois, A., Bergeron, J., Brown, R., Royer, A., Harvey, R., Roy, A., Wang, L. and Thériault, N. (2014). Evaluation of CLASS 2.7 and 3.5 simulations of snow properties from the Canadian Regional Climate Model (CRCM4) over Québec, Canada. J. of Hydrometeorology, 15 : 1325-1343.
  • Picard, G., Royer, A., Arnaud, L., and Fily, M. (2014) Influence of meter-scale wind-formed features on the variability of the microwave brightness temperature around Dome C in Antarctica. The Cryosphere, 8 : 1105-1119.
  • Roy, A., Royer, A. and Hall, R. (2014) Relationship between forest microwave transmissivity and structural parameters for the Canadian boreal forest. IEEE Geoscience and Remote Sensing Letters, 11(10) : 1802-1806.
  • Rutter, N., M. Sandells, C. Derksen, P. Toose, A. Royer, B. Montpetit, A. Langlois, J. Lemmetyinen, and J. Pulliainen (2014). Snow stratigraphic heterogeneity within ground-based passive microwave radiometer footprints : Implications for emission modeling. J. Geophys. Res. Earth Surf., 119, doi:10.1002/2013JF003017.
  • Bergeron J., A. Royer, R. Turcotte (2014). Snow cover estimation using blended MODIS and AMSR-E data for improved watershed-scale spring streamflow simulation in Quebec, Canada. Hydrological Processes, 28, 4626–4639, DOI: 10.1002/hyp.10123.
  • Picard, G., Brucker, L., Roy, A., Dupont, F., Fily, M., Royer, A., and Harlow, C. (2013) Simulation of the microwave emission of multi-layered snowpacks using the Dense Media Radiative transfer theory: the DMRT-ML model, Geosci. Model Dev., 6, 1061-1078, doi:10.5194/gmd-6-1061-2013.
  • Roy, A., Royer, A., Montpetit, B., Bartlett, P.A., and Langlois, A. (2013) Snow specific surface area simulation using the one-layer snow model in the Canadian LAnd Surface Scheme (CLASS). The Cryosphere, 7, 961-975, doi:10.5194/tc-7-961-2013
  • Kohn, J. and A. Royer, (2012) Microwave brightness temperature as an indicator of near-surface air temperature over snow in Canadian northern regions. International Journal of Remote Sensing, 33:4, 1126-1138.
  • Derksen, C., Smith, S. L., Sharp, M., Brown, L., Howell, S., Copland, L., Muelle, D. R., Gauthier, Y., Fletcher, C., Tivy, A., Bernier, M., Bourgeois, J., Brown, R., Burn, C. R., Duguay, C., Kushner, P., Langlois, A., Lewkowicz, A. G., Royer, A. and Walker, A. (2012) Varianility and change in the canadian cryosphere, Climatic Change, DOI: 10.1007/s10584-012-0470-0.
  • Dupont, F., Royer, A., Langlois, A., Gressent, A., Picard, G., Fily, M., Cliche, P. and Chum, M. (2012) Monitoring the melt season length of the Barnes Ice Cap over the 1979–2010 period using active and passive microwave remote sensing data. Hydrol. Process.. doi: 10.1002/hyp.9382
  • Dupont, F., Picard, G., Royer, A., Fily, M., Langlois, A., Roy, A., and Champollion, N. (2012) Modeling the microwave emission of bubbly ice; Applications to blue ice and superimposed ice in the Antarctic and Arctic, IEEE Transactions on Geosciences and Remote Sensing, Submitted, TGRS_2012-01104.
  • Langlois, A., A. Royer, C. Derksen, B. Montpetit, F. Dupont, and K. Goïta (2012) Coupling the snow thermodynamic model SNOWPACK with the microwave emission model of layered snowpacks for subarctic and arctic snow water equivalent retrievals. Water Resour. Res., 48, W12524, doi:10.1029/2012WR012133.
  • Montpetit B., Royer, A., Roy, A., Langlois, A. and Derksen, C. (2012) Snow microwave emission modeling of ice lenses within the snowpack using the Microwave Emission Model for Layered Snowpacks (MEMLS), Hydrological Processes.
  • Montpetit B., Royer A., Langlois A., Cliche P., Roy A., Champollion N., Picard G., Domine F., Obbard R. (2012) New short wave infrared albedo measurements for snow specific surface area retrieval, Journal of Glaciology, vol. 58, no. 211, doi: 10.3189/2012JoG11j248. Roy, A., Picard, G., Royer, A., Montpetit, B., Dupont, F., Langlois, A., and Derksen, C. (2012) Snow brightness temperature simulations driven by measurements of the specific surface area of snow grains, IEEE Transactions on Geoscience and Remote Sensing, Accepted, TGRS-2012-00591.
  • Roy, A., Royer, A., Wigneron, J.-P., Langlois, A., Bergeron, J., Cliche, P. (2012) A simple parameterization for a boreal forest radiative transfer model at microwave frequencies. Remote Sensing of Environment, 124, doi: 10.1016/j.rse.2012.05.020.
  • Rutter, N., Sandells, M., Derksen, C., Royer, A., Lemmetyinen, J., Toose, P., Montpetit, B., Langlois, A., and Pulliainen, J. (2012) Snow stratigraphic heterogeneity within ground-based passive microwave radiometer footprints: implications for emission modelling. Journal of Geophysical Research.
  • Brucker, L., Royer, A., Picard, G., Langlois, A. and Fily, M. (2011) Hourly simulations of the microwave brightness temperature of seasonal snow in Quebec, Canada, using a coupled snow evolution-emission model. Remote Sensing of Environment. 115, pp. 1966-1977. doi:10.1016/j.rse.2011.03.019
  • Langlois, A., Royer, A., Dupont, F., Roy, A., Goïta, K. and Picard, G. (2011) Improved corrections of forest effects on passive microwave satellite remote sensing of snow over boreal and subarctic regions. IEEE Transactions on Geoscience and Remote Sensing, Vol. 49(10 PART 2), art. no. 5771614, pp. 3824-3837.
  • Toure, A.M., Goïta, K., Royer, A., Kim, E.J., Durand, M., Margulis, S.A., Lu, H. (2011) A case study of using a multilayered thermodynamical snow model for radiance assimilation. IEEE Transactions on Geoscience and Remote Sensing, Vol.49 (8), art. no. 5756663, pp. 2828-2837.
  • Kohn J. and A. Royer (2010), AMSR-E data inversion for soil temperature estimation under snow cover, Remote Sens. Environ., 114(12), 2951–2961.
  • Langlois, A., Royer A. and Goïta, K. (2010). Analysis of simulated and spaceborne passive microwave brightness temperatures using in-situ measurements of snow and vegetation properties, Can. J. Remote Sensing, 36, S135–S148.
  • Langlois, A., Royer, A., Montpetit, B., Picard, G., Brucker, L., Arnaud L., Harvey-Collard, P., Fily, M. and Goïta, K. (2010) On the relationship between snow grain morphology and in-situ near infrared calibrated reflectance photographs. Cold Regions Science and Technology, 61, pp. 34-42. doi:10.1016/j.coldregions.2010.01.004
  • Roy, A., Royer, A., and Turcotte, R. (2010) Analyse de l’identification de la fonte de neige printanière avec QuickSCAT dans le sud du Québec, Canada, Journal canadien de télédétection, 36(2), pp. 89-98.
  • Roy, A., Royer, A., and Turcotte, R. (2010) Improvement of springtime streamflow simulations in a boreal environment by incorporating snow-covered area derived from remote sensing data, Journal of Hydrology, Vol.390, pp.35-44.
  • Royer, A. and S. Poirier (2010). Surface temperature spatial and temporal variations in Northern America from homogenized satellite SSMR-SSM/I microwave measurements and reanalysis for 1979-2008. Journal of Geophysical Research, 115, D08110, DOI:10.1029/2009JD012760.
  • Royer, A., K. Goïta, J. Kohn, and D. DeSève (2010). Monitoring dry, wet, and no- snow conditions from microwave satellite observations. IEEE Geos. Remote Sens. Letters, Vol. 7, No. 4, pp. 670-674. DOI: 10.1109/LGRS.2010.2045733
  • Turcotte, R., Fortier Filion, T.-C., Lacombe, P., Fortin, V., Roy, A. and Royer, A. (2010) Simulation hydrologique des derniers jours de la crue de printemps: le problème de la neige manquante, Hydrological Sciences Journal, 55(6), 872-882. doi: 10.1080/02626667.2010.503933
  • Vachon, F., Goïta, K., De Sève, D., and Royer, A. (2010). Inversion of a snow emission model calibrated with in situ data for snow water equivalent monitoring. IEEE Transactions on Geoscience and Remote Sensing, Vol. 48, Issue 1, pp. 59-71, DOI: 10.1109/TGRS.2009.2026892.
  • Langlois, A., Brucker, L., Kohn, J., Royer, A., Derksen, C., Cliche, P., Picard, G., Fily, M. and Willemet, J.M. 2009. Simulation of Snow Water Equivalent (SWE) using Thermodynamic Snow Models in Québec, Canada. Journal of Hydrometeorology, Accepted June 2009.
  • Toure A. M., Goïta K. Royer A., Mätzler C. and M. Schneebeli (2009). Near-infrared digital photography to estimate snow correlation length for microwave emission modeling. Applied Optics 48(1), 1-11, doi :10.1364/AO.47.006723.
  • Haboudane, D., F. Bonn et A. Royer(2008). Evaluation and predictability of terrain susceptibility to hillslope erosion at the regional scale using dem-derived indices and remotely sensed information. Télédétection, vol. 7, p. 373-391.
  • Royer A., F. Becker et P. Gagnon (2008), Trente-cinq ans d’observation de la Terre : de la photographie à l’électromagnétométrie, Télédétection, vol.7, p. 65-88.
  • Royer, A., M. Fily, G. Picard (2008). Évolution des températures de surface des régions polaires et subarctiques par télédétection satellite. Lettre PIGB-PMRC France, no 21, Changement global.