Introduction

Question 1

Explain the figure shortly

Answer 1

The figure shows a decrease in sea-ice cover in the Arctic for the month of November(measured with satellite). The monthly November ice extent for 1979 to 2019 shows a decline of 5.02 percent per decade relative to the 1980-2010 average. Arctic sea ice extent for November 2019 was 9.33 million square kilometers, the second lowest in the satellite record.

Question 2

What are the albedo to sea- ice and open water?

Answer 2

1. sea- Ice: albedo: 0.75. This means that 75% is reflected, and 25% is absorbed.
2. open water: albedo: 0.07 This means that 7% is reflected, and 93% is absorbed

Question 3

Explain the albedo feedback:

Answer 3

Higher ocean temperatures, more heat into the atmosphere. –> more ice melting –> more open water, small albedo –> more solar energy into the ocean –> and again, higher ocean temperatures, more heat into the atmosphere

Question 4

what can you say about the Eocene warm period in terms of the Arctic?

Answer 4

Warm period where the Arctic ocean had surface temperatures well above 10 ˚C (and broadly comparable solar forcing)

Question 5

Whys is the Nordic Seas and Scandinavia referred to as A Climate oasis?

Answer 5

1. 10-15°C warmer than latitude mean
2. Caused by atmospheric lows and ocean circulation
3. Dependency on heat import –> sensitive to climate changes
4. Local feedbacks –> strong signals