Editing Hydrosphere (section)

==Human impact==
The activities of modern humans have drastic effects on the hydrosphere. For instance, water diversion, human development, and pollution all affect the hydrosphere and natural processes within. Humans are withdrawing water from aquifers and diverting rivers at an unprecedented rate. The [[Ogallala Aquifer]] is used for agriculture in the United States; if the aquifer goes dry, more than $20 billion worth of food and fiber will vanish from the world's markets.<ref>{{cite journal |url= https://www.scientificamerican.com/article/the-ogallala-aquifer/ |title= The Ogallala Aquifer: Saving a Vital U.S. Water Source |last= Braxton |first= Jane |date= March 1, 2009 |website= Scientific American |doi= 10.1038/scientificamericanearth0309-32 |doi-broken-date= 1 November 2024 |access-date= March 26, 2020|url-access= subscription }}</ref> The aquifer is being depleted so much faster than it is replenished that, eventually, the aquifer will run dry. Additionally, only one third of [[rivers]] are free-flowing due to the extensive use of dams, levees, [[hydropower]], and habitat degradation.<ref>{{cite web|last=Carrington|first=Damian|date=May 8, 2019|title=Only a third of world's great rivers remain free-flowing, analysis finds|url=https://www.theguardian.com/environment/2019/may/08/only-a-third-of-worlds-great-rivers-remain-free-flowing-analysis-finds|access-date=March 26, 2020|website=The Guardian}}</ref> Excessive water use has also caused intermittent streams to become more dry, which is dangerous because they are extremely important for water purification and habitat.<ref>{{cite journal |last1=Stokstad |first1=Erik |title=Streams that flow only part of the year are getting even drier |journal=Science |date=13 August 2021 |volume=373 |issue=6556 |pages=724 |doi=10.1126/science.373.6556.724 |pmid=34385373 |bibcode=2021Sci...373..724S |s2cid=236998854 }}</ref> Other ways humans impact the hydrosphere include [[eutrophication]], [[acid rain]], and [[ocean acidification]]. Humans also rely on the health of the hydrosphere. It is used for water supply, navigation, fishing, agriculture, energy, and recreation.<ref>{{Cite book |last=Klige |first=R. K. |title=Global Studies Encyclopedic Dictionary |publisher=Value Inquiry Book Series |year=2014 |pages=267–269}}</ref>