10 . 5 Pea : Phenomena Extraction Algorithm

1. INTRODUCTION A phenomenon is defined as any state or process known through the senses rather than by intuition or reasoning, and thus is an observable event, especially something special or unusual. Many geophysical phenomena can be observed and monitored using space-based and ground-based sensors or simulated in numerical models. Research studies on geophysical phenomena rely on the data collected by these sensors or generated by the numerical models. A geophysical phenomenon in the context of the geoscience data can be characterized as a spatial region with the following: • As a spatial region significantly different from the rest of the image. • Having higher/lower than the average background intensity value and/or higher variation in intensity when compared to the remaining data points • Having a spatial extent that is much smaller than the rest of the data • Having a temporal extent, meaning the size and magnitude of the phenomenon and the variation within the region can change over time. Examples of geophysical phenomena include the hurricanes characterized by the strong vorticity and weather fronts characterized by the significant variations of local wind patterns.