Topics
Climate
35
Climatology
28
Ice on rivers, lakes, etc
8
Hydrology
7
Archaeological surveying
6
Environmental aspects
6
Antiquities
5
Hydroelectric power plants
5
Ice mechanics
5
Temperature
5
Geology
4
Measurement
4
Dams
3
Economic conditions
3
Freezes (Meteorology)
3
Ice
3
Economic aspects
2
Social conditions
2
Stream measurements
2
Air quality
1
Alaska Natives
1
Archaeological geology
1
Cultural property
1
Design and construction
1
Economic history
1
Economic surveys
1
Ethnology
1
Excavations (Archaeology)
1
Geological surveys
1
Historic sites
1
Municipal services
1
Paleontological excavations
1
Particles
1
Regional economics
1
Social aspects
1
Telephone surveys
1