Second, they took a second set of climate model simulations which were identical to the first set, except that CO2 concentrations were kept constant at 19th century levels. (globalwarmingsolved.com)
Schools will provide each child with the quantity and quality of schooling they need to learn at 21st century levels. (gse.harvard.edu)
These data indicate that local rates were generally at the 1 — 10 cm per century level (see Table 1). (skepticalscience.com)