Here's the end of the text presented in a question I posted previously.
The coastal ice in parts of Canada and Alaska has become quite brittle. Ice easily breaks away in large pieces and melts in the open ocean. Now there is also less sea ice in the Arctic Ocean. It happens because ice is floating into the Atlantic Ocean.
Scientists say that the lack of ice represents clear proof that the planet ___________ (WARM). Back in the past it could take three years to get through the waterway's thick ice successfully, now – just a few weeks.
I reckon, Present Continuous and Present Perfect are both possible there. However, I wonder if there is enough context to eliminate one of my choices and have the only one left?