Unalakleet video camera 1 variance image

Two video cameras overlook the coast from atop a windmill tower in Unalakleet, Alaska where they look westward over Norton Sound. Every half hour during daylight hours, the cameras collect snapshots and video for 10 minutes. Today’s most recent image from camera 1 is shown here. Please note that it takes 10 minutes for the images to be posted, once they are collected by the camera. This is a variance Image, showing the standard deviation of pixel intensity throughout the video frames. It's useful for determining how much variation or movement is occurring at a given location. [Larger version]

Learn more about how the USGS uses these images to study wave dynamics.