I don't believe that ice in both the poles will melt at the same time. The transformation is usually in such a way that the ice in existing regions will melt and ice formation will take place in a region where there were no ice before. One place will start to feel more heat and another place will start to feel more cold. That is how the transformation usually happens. In either ways it is quite dangerous. The following consequences can happen:

• Many aquatic life will be affected. 
• The animals will suffer from too much of heat and too much of cold. 
• The living being will not be able to get proper and consistent food. 
• The living beling will have to start adapting to so many new things. 

Polar bears and penguins will start to have really tough times. They will not be able to survive high temperature. We might see a huge decline in their population and at the same time there will also be a possibility where some of their species can go extinct.