TORONTO -- Melting Arctic sea ice is a very big problem.

Across the Arctic, ice levels are at some of their lowest levels ever.

In some regions, such as Greenland, scientists say the ice sheet may already be at a point of no return, meaning there may no longer be any way to avert its eventual collapse.

All of this melting ice directly contributes to rising sea levels, global warming and other major long-term climate issues.

But there are short-term effects too, and they're particularly problematic for two iconic Canadian mammals.

In the video at the top of this page, CTV News Science and Technology Analyst Dan Riskin explains how melting ice is endangering the lives of narwhals and polar bears.