What Should the Climate Goal Be, 1.5°C or 2°C?

The Paris Agree­ment on cli­mate change signed by 195 coun­tries in Paris on De­cem­ber 11, 2015, calls on coun­tries to re­duce green­house gas emis­sions in order to re­strict tem­per­a­ture rise to well below 2°C from pre-in­dus­trial lev­els. The tar­get of a 1.5°C limit on tem­per­a­ture rise has now ex­plic­itly been iden­ti­fied as a goal to be achieved. The de­mand to re­strict tem­per­a­ture rise to 1.5°C rather than 2°C has long been ar­tic­u­lated by the group of coun­tries most vul­ner­a­ble to the im­pact of cli­mate change, since a 2°C rise in tem­per­a­tures will lead to greater risks from ocean acid­i­fi­ca­tion and ex­treme events in these coun­tries and will very likely have a sig­nif­i­cant im­pact on crop pro­duc­tion as well. At the same time, large less-de­vel­oped coun­tries such as India have been op­posed to this more strin­gent tar­get as it would leave very lit­tle car­bon space for gov­ern­ments to pro­vide basic needs to their peo­ple. This paper un­der­takes a com­par­a­tive re­view of the im­pact of and mit­i­ga­tion re­quire­ments im­plied by the 1.5°C and 2°C tar­gets and dis­cusses the im­pli­ca­tions of the Paris Agree­ment in the light of this re­view.