These are the most frequently used words in this book.
1990
2000
actually
air
almost
although
areas
average
better
between
billion
cancer
cause
century
change
co2
cost
countries
course
death
developing
does
effect
emissions
energy
environment
environmental
estimated
estimates
even
ever
far
figure
first
food
forest
future
get
global
good
growth
higher
however
human
important
increase
increased
increasing
ing
ipcc
large
less
level
life
look
may
means
million
models
new
now
number
often
oil
part
people
per
percent
pesticides
point
pollution
population
price
problem
production
rate
resources
risk
see
seems
seen
should
shows
since
source
still
studies
temperature
thus
time
tion
today
total
two
use
used
warming
water
world
years