- Climatology 5
- Geophysics/Geodesy 5
- Oceanography 5
- Atmospheric Sciences 3
- Math. Appl. in Environmental Science 3
- Meteorology 3
- Terrestrial Pollution 3
- Waste Water Technology / Water Pollution Control / Water Management / Aquatic Pollution 3
- Climate Change/Climate Change Impacts 1
- Climate, general 1
- Earth System Sciences 1
- Environmental Science and Engineering 1
- Geography, general 1
- Monitoring/Environmental Analysis 1