Earth & Environmental Sciences
mass extinction
100%
volcanic eruption
94%
comet
52%
crater
44%
volcanism
40%
Permian
40%
flood basalt
37%
asteroid
32%
periodicity
30%
Permian-Triassic boundary
29%
sea level
27%
ocean
25%
Cretaceous-Paleogene boundary
24%
climate
23%
aerosol
21%
Holocene
21%
solar system
20%
Triassic
18%
cooling
18%
eccentricity
18%
cratering
17%
barrier island
17%
explosive
14%
climatic effect
13%
ice
13%
Deccan Traps
13%
magma
12%
ash
12%
sulfur
11%
submergence
11%
dust
11%
effect
11%
ejecta
11%
planet
11%
indicator
10%
greenhouse effect
10%
winter
10%
gymnosperm
10%
transgression
10%
seafloor
10%
ice core
10%
climate change
10%
global climate
9%
hot spot
9%
volcano
9%
marsh
9%
Physics & Astronomy
volcanic eruptions
42%
extinction
28%
comets
27%
volcanology
25%
aerosols
19%
craters
19%
asteroids
17%
cycles
13%
cratering
12%
plumes
10%
solar system
10%
Cretaceous-Tertiary boundary
9%
carbon dioxide
9%
global warming
9%
climate
8%
causes
8%
stratigraphy
8%
galaxies
7%
greenhouse effect
7%
magma
7%
exobiology
7%
estimates
7%
periodic variations
6%
sulfates
6%
basalt
6%
Antarctic regions
6%
dust
6%
sea floor spreading
6%
winter
5%
sea level
5%
geomagnetism
5%
ice
5%
impactors
5%
Oort cloud
5%
domes
5%
heating
5%
sun
5%