analysis
atmosphere
blue
carbon
celsius
co2
concept
dioxide
discharge
earth
ecological
ecology
efficiency
efficient
emission
energy
environment
environmental
gas
global
globalization
globe
green
harm
harmful
heat
heating
hot
idea
issue
measurement
planet
problem
production
protect
protection
report
research
save
saving
scale
science
scientific
symbol
temperature
thermometer
warm
warming
warmth
weather