Electromagnetic emissions in thermal infrared bands are an important research topic on pre-earthquake studies. Satellite thermal data have been investigated by many independent research groups looking for their anomalous behaviour before main earthquake's occurrences. Among them, geosynchronous satellite data are reported as less prone to artefacts during data processing. In this work, the Night Thermal Gradient (NTG) algorithm is presented, which has been specifically proposed for geostationary thermal infrared data processing. NTG method relies on the exploitation of high temporal resolution data to find coherent low frequency components of a hypothetical precursory signal of seismic activity. In this paper, the method is presented by giving details about the applied procedures, steps, theoretical assumptions and results obtained during the studies of L'Aquila 2009 earthquake and the seismic activity of Central Italy and Sardinia.

热红外波段中的电磁辐射是地震前研究的重要研究课题。许多独立研究小组已经对卫星热数据进行了调查，以寻找其在大地震发生前的异常行为。其中，据报道地球同步卫星数据在数据处理过程中不易出现伪像。在这项工作中，提出了夜间热梯度（NTG）算法，该算法专门针对地球静止热红外数据处理而提出。NTG方法依赖于高时间分辨率数据的利用来找到假设的地震活动前兆信号的相干低频分量。在本文中，通过提供有关应用程序，步骤，