1 A review of research involving human subjects by the IRB chair or by one or more experienced reviewers designated by the chair from among members of the IRB in accordance with the requirements set forth in 45 CFR 46.110. 2  Experimental subject (as defined by Department of Defense, or DOD).
Anvil clouds are the icy upper portions of cumulonimbus thunderstorm clouds that are caused by a rising of air in the lower portions of the atmosphere. When the rising air reaches 40,000-60,000 or more feet, it tends to spread out in a characteristic anvil shape.
Thunderstorms can look like tall heads of cauliflower or they can have âanvils.â An anvil is the flat cloud formation at the top of the storm. An anvil forms when the updraft (warm air rising) has reached a point where the surrounding air is about the same temperature or even warmer.