EARTHSS 21 Lecture Notes - Lecture 14: Narwhal
23 Jul 2016
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Lecture 14: implications of summer sea-ice free arctic: to monitor sea ice, we would want to measure sea ice extent (what area it covers; the depth. Send people out to take measurements of sea ice in person: monitor depth/drift. To measure sea ice thickness, we can time sound waves from submarine to sea ice (how long it takes to bounce back gives us a sense of the distance between the sea ice and submarine) Satellites beam out radio waves and bounces back (obtains a distance- height of the ice above sea level) If you know what"s above, you can calculate what"s underneath (ice) Southern hemisphere: (antarctic) sea ice extent increasing in the winter and summer: northern hemisphere: sea ice extent decreasing in the winter and summer (most decrease in the summer) 7 3. 5 (only have half of sea ice left) Tipping points: irreversible change where we go from sea ice in the summer to no sea ice at all.
