The continual increase in jet air traffic and coincident rise in jet engine efficiency has resulted in an apparent increase in cirrus cloudiness through the formation of persistent contrails. Projections suggest a fivefold increase in high-altitude air traffic between 1990 and 2050. Because the upper troposphere is estimated to be suitable for persistent contrail formation at any given time, it is expected that contrail coverage will increase by the same factor or more. To evaluate the potential impact of these contrails on climate, it is necessary to determine the coverage and radiative properties of contrails. This paper decribes a methodology for detecting contrails and retrieving their characteristics from high resolution satellite data and the results of applying this methodology to Advanced Very High Resolution Radiometer (AVHRR) and Terra Moderate Resolution Imaging Spectroradiometer (MODIS) data over the USA. An image processing technique is used to determine the location and coverage of linear contrails in 11-12-µm brightness temperature difference images. A multispectral analysis method incorporating a set of theoretical reflectance and emittance models is used to retrieve the contrail optical properties. Mean reflectances and temperatures are computed separately for the contrail pixels and the surrounding pixels to determine directly the radiative forcing of the contrails. Results are presented for selected areas of the USA during 1998 and 2001.