Subject
Meteorology
22
Hydrology
12
Water resources development
10
Hydrology Research
9
Water-supply
9
Groundwater
7
Rain and rainfall
7
Water-supply Research
5
Coal mines and mining
3
Snow surveys
3
United States
3
Water resources development Research
3
Water table
3
Agriculture Economic aspects
2
Air Pollution
2
Air traffic control
2
Archives
2
Arizona Climate
2
Coal trade
2
Colorado Climate
2
Earthquakes
2
Educational exchanges
2
Forests and forestry
2
Idaho Climate
2
Montana Climate
2
Nevada Climate
2
New Mexico Climate
2
Oregon Climate
2
Precipitation (Meteorology)
2
Radar air traffic control systems
2
Research
2
Scholarships
2
Securities
2
Stream measurements
2
United States Commerce
2
United States Economic conditions
2
Utah Climate
2
Vital statistics Data processing
2
Wyoming Climate
2
Accounting
1
Agricultural credit
1
Agricultural industries
1
Agricultural laborers
1
Agriculture
1
Agriculture and state
1
Air travel
1
Alaska Climate
1
Appropriations and expenditures
1
Aquatic plants
1
Aquatic plants Geographical distribution
1
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