Decadal-mean seasonal and annual temperature anomalies (in °C). (a) For the Eurasian (solid line) and North American (dashed line) land masses. (b) For the contiguous United States, using data from the National Climatic Data Center described in Karl et al. (1984b) (solid line) and from the gridded temperature anomaly fields of Jones et al. (1986a) (dashed line). (c) For the eastern (solid line) and western (dashed line) United States. (d) For the state of Colorado (solid line) and the Platte River climatic division of Colorado (dashed line).