These are the most frequently used words in this book.
air
american
among
animals
area
between
billion
book
brownlash
business
case
cause
change
chemicals
climate
companies
con
costs
course
earth
economic
ecosystems
effects
energy
environment
environmental
even
first
food
forests
future
global
good
greenhouse
growth
health
human
humanity
increase
industry
ing
issues
land
less
life
may
might
million
nations
natural
need
new
now
number
often
ozone
part
people
per
percent
pesticides
policy
population
problems
production
public
re
regulations
research
resources
result
risks
science
scientific
scientists
should
since
society
sources
species
statement
states
support
system
thus
time
tion
today
toxic
trends
united
use
view
warming
water
without
work
world
years
yet