Scientists believe the gases &#151; mostly a result of burning fossil fuels &#151; trap heat into the earth's atmosphere, contributing to global warming which could cause disastrous weather changes and floods over the next 100 years.
(Scientists; believe; the gases &#151) (global warming; could cause; disastrous weather changes and floods; T:over the next 100 years)
Scientists global warming
believe could cause
the gases &#151
disastrous weather changes and floods T:over the next 100 years