In northern Norrland, which is part of the Swedish Arctic, winter has long been so cold that the number of days with temperatures around zero degrees has been few. But now they are becoming more and more common. It shows figures from SMHI.

- The trend is that the days when you pass zero during the day have become more winter in northern Sweden, says climate researcher Gustav Strandberg at SMHI.

So-called zero passes create problems for, among other things, the reindeer industry because ice is often formed in the ground when the temperature changes from plus to minus. Then the reindeer will not reach the lichen and they will be forced to feed.

Looks to hit more in the long run

Over the past 100 years, the tree line on the calf has also climbed 100-150 meters, according to figures from the county administrative board.

And although winter 2020 has been very snowy in the mountains, the trend over time is that the snow season will be shorter and the growing season longer - a natural consequence of it getting warmer, Gustav Strandberg says.

- This is probably the worst development imaginable for mountain tourism. It is very difficult to hike when it is very snowy, he says.

For example, reducing emissions from aircraft through corona can have any long-term effect?

- We still have quite a lot of emissions. As long as we have it, the levels of greenhouse gases will increase in the atmosphere and this will drive a continued climate change. We might be able to see that the heating is slightly weakened if we continue for one or more years.