Earth's poles are warming faster than the rest of the planet.
One reason is that energy is carried to the poles by large weather systems.
The Arctic includes an ocean covered by sea ice.
Arctic sea ice melts in Summer and then refreezes in Winter.
The area of Arctic sea ice is largest in March each year, and at its lowest each September.
It is reducing over time - the graph comes from the US National Snow and Ice Data Center.
Research suggests the remarkable decline of Arctic sea ice over the last century is far beyond anything seen for a long time.
The sea ice surrounding Antarctica melts almost to the coast each summer.
For a useful comparison of Antarctic and Arctic sea ice follow this link……