Natural gas is mostly methane. In my piece on the Cornell study, my subhed was âLeakage of methane from fracking boosts shale gas global warming impact.â I didnât note until several paragraphs later that âNatural gas is composed largely of methane,â which comes from the second sentence of the study itself.
Tornado strength is currently measured on what is called the Enhanced Fujita Scale (adapted from the simpler Fujita Scale in 2007), which gives the tornado a rating from 0 to 5 based on estimated wind speeds and the severity of the damage.
Fire Intensity and Severity. Fire severity is a measure of the physical change in an area caused by burning (Sousa 1984). Although fire intensity is a key component of burn severity, these are two distinct features of fire; the terms are often incorrectly interchanged. Used correctly, fire intensity refers to the rate at which a fire produces heat at the flaming front and should be expressed in terms of temperature or heat yield. Fire severity, on the other hand, describes the immediate effects of fire on vegetation, litter, or soils.