Final answer:
The rise in sea level by the end of the century under RCP8.5 as compared to RCP2.6 could be approximately four times higher, considering the higher rates of ice melting and ocean expansion due to increased greenhouse gas emissions.
Step-by-step explanation:
The rise of sea level by the end of the century under scenario RCP8.5 as compared to scenario RCP2.6 can be estimated by examining the increased rates of melting ice and expansion of ocean waters due to global warming. With the projections of temperature and its impacts on sea levels available, we can infer that the rise in sea level by the end of the century could be significantly higher under the RCP8.5 scenario. RCP8.5 assumes a higher rate of greenhouse gas emissions compared to the lower emission scenario RCP2.6. As a result of the greater emissions, there will be more melting of ice sheets and glaciers and a greater expansion of water as it warms, leading to an exponential increase in sea levels.Based on the information considered, it's reasonable to suggest that out of the given options, the sea level could rise approximately four times higher under scenario RCP8.5 compared to RCP2.6. This is consistent with projections that indicate a potential rise in sea levels if high emissions and warming continue unchecked, resulting in significant melting of ice and expansion of seawater.