Water is continuously circulated within the system using a peristaltic pump via a water tube, illustrated in Figure , to both regulate the internal temperature and empty excess water from within the internal chamber air cavity. The temperature of the internal sample environment is controlled by the water temperature, which is regulated by an immersion heater and programmable controller. A dry nitrogen line runs in tandem with the water circulation line to control the relative humidity of the internal chamber by releasing dry nitrogen into the base of the internal chamber where the air cavity is located within the submerged enclosure. A base plate that holds the sample above the water line, shown at the bottom of Figure , has a sealable door that opens when a fan, shown in Figure , is activated to allow airflow into the chamber. The relative humidity of the sample environment is precisely controlled by tuning the flow rate of dry nitrogen into the air cavity and by circulating moist air from the water surface into the sample environment. Samples are mounted on the sample plate, shown in Figure , at an angle normal to the camera line of sight. A ThorLabs DCC1645C CMOS camera (with an infrared filter removed from it) is mounted statically to a rail above the internal chamber to image the samples. A Color Checker card is placed inside the internal chamber to calibrate the camera color settings. A quartz disk is placed on the top of the chamber in the aerial transmission pathway from the samples to the camera to minimize optical aberrations due to the chamber material and water. The sample base plate has a thermoelectric module installed underneath to provide the option of directly heating the samples via conduction, as in the first generation chamber. A sensor, shown in Figure , is mounted within the internal chamber to control the temperature and relative humidity of the internal environment. Additionally, a separate humidity-temperature tracker is used for tracking the chamber conditions, as in Gen. 1 chamber. The culminating design of the MIT Environmental Chamber Gen. 2 gives researchers better control over high-throughput materials degradation experiments in extreme humidity conditions through the precise programming of dew point, temperature, relative humidity, and illumination spectrum within the sample environment.