What is the atmospheric pressure at the bottom of the Grand Canyon?

The atmospheric pressure at the bottom of the Grand Canyon is approximately 90 kPa (kilopascals), which is slightly lower than the standard atmospheric pressure at sea level (about 101.3 kPa). This decrease in pressure is primarily due to the elevation of the Grand Canyon, which is about 1,200 meters (around 4,000 feet) above sea level. As altitude increases, the atmospheric pressure decreases, resulting in the lower pressure observed at the canyon's depth.