Life would be considerably easier for US Border Patrol agents if all illicit activity in their sectors happened during daylight hours. Unfortunately, the majority of the US-Mexico border can be described as “the middle of nowhere,” illuminated at night only by the moon. Drug traffickers, human smugglers and migrants in their charge use the cover of darkness to their advantage, resting during the hot daylight hours and making border crossing attempts at night.
Utter darkness, harsh terrain and a variety of cover and concealment options pose several challenges for both Border Patrol agents and other law enforcement officers operating in border areas. Fortunately, evolving technology allows agents to literally see in the dark.
If you use the term “night vision,” most will call to mind an action-adventure movie scene where the characters’ points of view are bathed in green. This picture is obtained in three main ways – through image intensification, active illumination or thermal imaging. With image intensification, a night vision device magnifies the amount of photons received from natural light sources, such as the moon or stars. The image intensifier is a vacuum-tube based device that can generate an image from a very small number of photons so that a dimly lit scene can be viewed in real time by the naked eye via visual output.
Active illumination is a bit more complex. It combines image intensification technology with an active source of illumination in the infrared range of the color spectrum. Active illumination devices are sensitive to light in this spectral range and can produce images with clarity higher than those produced with image intensification.
Thermal imaging uses differences in temperature rather than the manipulation of ambient light to help users see in the dark. The slightest differences in thermal radiation emitted by living things and objects can be detected by thermal imaging devices, painting a digital black-and-white picture also often portrayed in movies. These devices are often combined with other night vision technologies, particularly on aircraft, and are commonly referred to as “FLIR” (forward-looking infrared).
Thermal imaging systems in particular are playing a large role in the current iteration of the virtual border fence project. This will involve a series of integrated fixed tower (IFT) positions along parts of the border that require more remote monitoring. The towers use both day and night cameras and sensors – including thermal imaging devices – that are designed to operate in Arizona’s often-brutal environment. Border Patrol agent Jose Verdugo told Popular Mechanics in January 2016 that the IFT system, which enables agents to accurately monitor areas previously unobserved, is like “turning on a light switch” along the dark, mysterious border.
Sylvia Longmire, Senior Contributing Editor, has been a frequent contributor to Homeland Security Today for many years. She is author of, Border Insecurity: Why Big Money, Fences and Drones Aren’t Making Us Safer and, Cartel: The Coming Invasion of Mexico’s Drug Wars.