change carbon cycle title level

Author: oscarbranson

book/00_intro/l2.md

@@ -124,7 +124,7 @@ Eddies in the atmosphere (storms, left) and the ocean (right).
 Where will you see this elsewhere in the course?
 We will revisit these topics again in Lent term in the first 9 lectures on the physics of the global environment (Lectures 26-33), and we will consider the physical and chemical structure of the atmosphere in Lecture 19 later this term.
 
-# The Carbon Cycle 
+## The Carbon Cycle 
 
 The carbon cycle refers to the movement, or exchange, of carbon around the planet through various **reservoirs**.
 Carbon is important as a gas because in its oxidized form ($\mathrm{CO_2}$) and in its reduced form ($\mathrm{CH_4}$), it is the strongest greenhouse gas in our atmosphere, keeping the planet warm.

book/_toc.yml

@@ -56,16 +56,16 @@ chapters:
   - file: 06_oceancarbon/03_biopump
   - file: 06_oceancarbon/04_carbonatepump
   - file: 06_oceancarbon/05_futureoceans
+# - file: 08_polarcasestudy/intro
+#   sections:
+#   - file: 08_polarcasestudy/l44
+#   - file: 08_polarcasestudy/l45
 - file: 07_landcarbon/intro
   sections:
   - file: 07_landcarbon/l40
   - file: 07_landcarbon/l41
   - file: 07_landcarbon/l42
   - file: 07_landcarbon/l43
-# - file: 08_polarcasestudy/intro
-#   sections:
-#   - file: 08_polarcasestudy/l44
-#   - file: 08_polarcasestudy/l45
 - file: 10_energytransitions/intro
   sections:
   - file: 10_energytransitions/l49