ENV100H1 Lecture 15: Water budget & water resources
7
ENV100H1 Full Course Notes
Verified Note
7 documents
Document Summary
Where is the water on earth mostly in oceans. 2. 5% is fresh water which can be used by humans. 70% locked into glacials + snow covers (not available) 30% in groundwater- slow turnover (takes long time to replenish) 0. 9% locked in soil moisture, swamp water + permafrost (not available) 0. 3% freshwater lakes + river storage (actually ows + available/renewable) very small portion of total water on earth. Is there enough freshwater? global runo on land: 40700km^3/year remote ow-19% (no one lives there!!!) uncultured oodwater-50% (all falls at the same time) accessible runo -31% used by humans (direct/in stream)-17% of total (half of accessible water=accessible runo ) Use of groundwater average recharge rate=0. 1-3% per year very slow process of percolation that runs into groundwater several large reservoirs in the world overused taking more out than what is recharged overdrawing groundwater very large volume. Gaza- near mediterranean- salt water will be drawn (salinization) % of population reliant on groundwater in canada.
