Fill in the blanks with an appropriate word in each gap.

In recent years there have been many alarming reports that world’s climate is undergoing a  significant changE- All these reports provide (a) ___evidence (b) ___  world's temperatures are  increasing day by day. This increase in global (c) ___  is caused (d) ___  increased amounts of carbon  dioxide (e) ___  the earth. Most climatologists (f) ___  that greenhouse effect is the likely (g) ___ of  this global warming. It may harm human (h) ___  seriously.