The National Academy of Sciences Polar Research Board Report Glaciers, Ice Sheets, and 

 Sea Level (Meier et al. 1985) examined the possible glacial contribution to sea level rise by the 

 year 2100. The panel endorsed estimates that alpine (Meier 1984) and Greenland (Bindschadler 

 1985) glaciers would each contribute 10 to 30 centimeters. Thomas (1985) estimated that the 

 antarctic contribution resulting from a four- degree warming would most likely be 28 cm, but 

 could be as high as 2.2 meters. However, the panel concluded that the antarctic contribution 

 could be anywhere from a 10- centimeter drop (due to increased snowfall) to a one-meter rise. 



Hoffman et al. (1986) revised their earlier projections in light of the glacial process models 

 developed in the Polar Board report and new information on future concentrations provided by 

 Nordhaus and Yohe (1983) and Ramanathan et al. (1985). Although the revised assumptions had 

 a minor impact on their estimates of thermal expansion, it substantially lowered their estimates 

 of snow and ice contributions until after 2050. They estimated the rise by 2025 to be between 10 

 and 21 cm, and by 2075 to be between 36 and 191 cm. 3 Thomas (1986) estimated the likely rise 

 through 2100 to be 64 to 230 cm. 



TABLE 1-1 



ESTIMATES OF FUTURE SEA LEVEL RISE (centimeters) 



Year 2100 by Cause (2085 in the case of Revelle 1983): 



Revelle (1983) 



Hoffman et al. 

 (1983) 



Meier et al. 

 (1985) 



Hoffman et al. 

 (1986) 



Thomas (1986) 



Thermal 

 Expansion 



30 

 28-115 



28-83 

 28-70 



Alpine 

 Glaciers 



12 



b 



10-30 



12-37 

 14-35 



Greenland 

 12 



b 



10-30 



6-27 

 9-45 



Antarctica 



-10 - +100 



12-220 

 13-80 



Total 

 70 



56-345 



50-200 c 



57-368 

 64-230 



Total Rise in Specific Years 



2000 



.d 



2025 



2050 



2075 



2085 



2100 



a Revelle attributes 16 cm to other factors. 



b Hoffman et al. (1983) assumed that the glacial construction would be one to two times the 



contribution of thermal expansion, 

 c This estimate includes extrapolation of thermal expansion from Revelle (1983). 

 d Only Hoffman et al. made year-to-year projections for the next century. 



8 



