ozone layer

noun 0.776

ozone

noun 0.716

ozone shield

noun 0.684

hole

noun 0.630

black hole

noun 0.620

blue hole

noun 0.606

air hole

noun 0.589

donut hole

noun 0.579

sinkhole

noun 0.573

ozone therapy

noun 0.568

white hole

noun 0.555

ionosphere

noun 0.539

pothole

noun 0.534

stratosphere

noun 0.533

security hole

noun 0.523

wormhole

noun 0.522

greenhouse effect

noun 0.516

ozonization

noun 0.515

biozone

noun 0.514

death zone

noun 0.513

troposphere

noun 0.513

oxygen depletion

noun 0.512

tropopause

noun 0.509

nanohole

noun 0.508

sound hole

noun 0.507

south pole

noun 0.506

blowhole

noun 0.505

eyehole

noun 0.504

global warming

noun 0.504

earhole

noun 0.502