A HIPPO took off from a windswept airfield in Colorado today, as  ICE-T waited in a nearby hangar, getting ready for a summer trip to the Caribbean.

OK, OK, enough fun with acronyms. HIPPO and ICE-T are flying climate laboratories, one in a Gulfstream V jet, the other in a refurbished C-130 military cargo plane.

Unlike its animal namesake, HIPPO is actually a rather sleek aircraft, fitted with equipment and a crew of 10, that makes flights of  eight hours or more at a go, sampling the atmosphere around the Pacific Basin, from near the North Pole to just off the coast of Antarctica. HIPPO is actually a combination of two acronyms: HIAPER Pole-to-Pole Observations. HIAPER itself stands for High-performance Instrumented Airborne Platform for Environmental Research. Quite a mouthful.

Unlike most Gulfstream V’s — usually used as corporate jets — this one has no in-flight bar. (Roger Wakimoto, the director of the National Center for Atmospheric Research, which manages the program along with the National Science Foundation, said the bar was one of the first things to go after the plane was delivered.)

HIPPO takes off steeply and then flies in a sawtooth pattern, rising to 28,000 feet and then dipping to just 1,000 feet above the water or land. The point of this roller-coaster flight is to figure out how climate-warming carbon dioxide and other trace gases is distributed, not just at Earth’s surface but up to the edge of the troposphere, the lowest layer of the atmosphere, where most weather occurs. Learn more about this project here.