Topics
Climate
25
Climatology
18
Ice on rivers, lakes, etc
8
Hydrology
7
Ice mechanics
6
Environmental aspects
5
Temperature
5
Hydroelectric power plants
4
Dams
3
Freezes (Meteorology)
2
Ice
2
Measurement
2
Stream measurements
2
Economic aspects
1
Economic conditions
1
Economic history
1
Regional economics
1
Roads
1
Social aspects
1
Social conditions
1