A combination picture shows St. Basil's Cathedral before (L) and during Earth Hour in Moscow March 28, 2015. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 p.m. local time, is meant as a show of support for tougher action to confront climate change. REUTERS/Sergei Karpukhin TPX IMAGES OF THE DAY

SERGEI KARPUKHIN / Reuters