face air temperature, increase in global meanrates of precipitation and evaporation, rising of sea levels. An increase in the surface airtemperature would cause rates of evaporation to increase, causing the water vapor in theair to rise. The positive feedback to the surface temperature increase is that is will lead toa more intense hydrological cycle, with more precipitation events (Kattenberg). Anotherpossible consequence of greenhouse gas induced climate change is elevated sea levels. The main cause for sea level fluctuation is due to thermal expansion and the melting ofglaciers, both are responses to higher air temperatures. Measurements taken from 93' to98' indicate a melt rate from Greenland's ice sheet of 1 meter a year (Krabill). There havebeen measurements of the sea levels also, they indicate a rise of about 10 - 25 cm a year(Douglas).All of these predictions were made by constructing models that help scientistpredict the climate change if the Green House Gases continue to rise at a steady rate. Although scientist are fairly confident in these models there is room for error in thesemodels. Despite the gains there are a number of features of the climate system that arestill crudely represented in climate models. The models are restricted in their ability toaccurately represent terrain effects and to simulate processes that occur on a smaller scale. Other shortcomings in the climate models is their inability to actually portray the effects ofaerosols, precipitation, and clouds and changes in solar irradiance. For these and otherreasons there remains scientific uncertainties in model predictions, including uncertaintiesin the predictions of local effects of climate change, occurrence of extreme weatherevents, effects of aerosols, changes in clouds, shifts in precipitation, and even changes inocean circulation (Hansen). Aerosols are a big concern for model analysts, because aerosols are a principlesource of uncertai...
