A considerable fraction of the wintertime sea-ice production on Arctic shelf areas is assumed to take place in the Laptev Sea polynya. Thus, monitoring of thin-ice distribution and growth within the polynya is important to determine heat loss and ice formation rates. We use a high-resolution helicopter-borne dataset of ice-surface temperatures measured during a field experiment in March/April 2009 to derive the thickness of thin ice within the polynya. Based on these data, we introduce modifications of an existing surface energy-balance model to infer thin-ice thicknesses from thermal infrared satellite data. Additionally, a sensitivity study for thin-ice thicknesses from MODIS and AVHRR data is performed with respect to the parameterization of turbulent fluxes and used atmospheric data.