|
15. 云和气候变化预测 1996年04月北美 D9604 As of the late 1980s, neither theorists nor large-scale computer climate models could accurately predict whether cloud systems would help or hurt a warming globe. Some studies suggested that a four percent increase in stratocumulus clouds over the ocean could compensate for a doubling in atmospheric carbon dioxide, preventing a potentially disastrous planetwide temperature increase. On the other hand, an increase in cirrus clouds could increase global warming. That clouds represented the weakest element in climate models was illustrated by a study of fourteen such models. Comparing climate forecasts for a world with double the current amount of carbon dioxide, researchers found that the models agreed quite well if clouds were not included. But when clouds were incorporated, a wide range of forecasts was produced. With such discrepancies plaguing the models, scientists could not easily predict how quickly the worlds climate would change, nor could they tell which regions would face dustier droughts or deadlier monsoons. 15.1. The author of the passage is primarily concerned with confirming a theory supporting a statement presenting new information predicting future discoveries reconciling discrepant findings 15.2. It can be inferred that one reason the fourteen models described in the passage failed to agree was that | 
