Sensitivity of a global climate model to an increase of CO₂ concentration in the atmosphere.

This study investigates the response of a global model of the climate to the quadrupling of the CO₂ concentration in the atmosphere. The model consists of 1) a general circulation model of the atmosphere, 2) a heat and water balance model of the continents, and 3) a simple mixed layer model of the oceans. It is found that the warming of the model atmosphere resulting from the CO₂ increase has significant seasonal and latitudinal variation. The warming of the model atmosphere results in an enrichment of the moisture content in the air and an increase in the poleward moisture transport. The additional moisture is picked up from the tropical ocean and is brought to high latitudes where both precipitation and runoff increase throughout the yr. Further, the time of rapid snowmelt and maximum runoff becomes earlier. -from Authors