teragrams
A teragram is a unit of mass in the metric system, equal to one trillion (10^12) grams. It is equivalent to 10^9 kilograms or one petagram. The prefix "tera-" signifies a factor of 10^12, making a teragram a very large unit of mass. Teragrams are typically used to measure quantities of materials on a global or continental scale, such as the mass of atmospheric gases, the amount of annual precipitation, or the total mass of certain types of geological formations. For instance, the Earth's atmosphere has a mass estimated to be in the order of quadrillions of teragrams. Similarly, the mass of water in the world's oceans is measured in exagrams, which are a thousand teragrams. The use of teragrams helps to simplify the representation of extremely large numbers that would otherwise be cumbersome to express using smaller units. It is one of several metric prefixes that allow for convenient expression of very large or very small quantities.