Unalakleet video camera 1 time exposure
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 time-exposure (timex) 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 time-averaged image of all frames over 10 minutes, which smooths away surface waves and helps determine the location of persistent wave-breaking (indicative of shallow sandbars). [Larger version]
Learn more about how the USGS uses these images to study wave dynamics.