View source for Earth:Community Collaborative Rain, Hail and Snow Network

{{Short description|International citizen science project}}
[[File:Community Collaborative Rain, Hail and Snow Network logo.svg|200px|thumb|right|The CoCoRaHS logo]]
The '''Community Collaborative Rain, Hail and Snow Network''', or '''CoCoRaHS''', is a network of volunteer weather observers in the {{wipe|United States}}, {{wipe|Canada}}, and the Bahamas that take daily readings of precipitation and report them to a central data store over the [[Internet|internet]]. The program is an example of [[Citizen science|citizen science]].

==History==
The network was started in 1997 in Larimer County, Colorado, after a [[Earth:Flash flood|flash flood]] in Spring Creek killed five people<ref name=Browning2006>{{cite news|last1=Browning|first1=Tom|title=Lessons from a killer flood|url=http://www.denverpost.com/headlines/ci_4104577|accessdate=27 March 2015|work=The Denver Post|date=2006-07-30}}</ref> and damaged structures in the city of Fort Collins, Colorado, including hundreds of millions of dollars in damage to the Colorado State University campus.<ref name=FC1997>{{cite web |url=http://www.ci.fort-collins.co.us/oem/historical-flooding.php |title=Flooding Timeline in Fort Collins  |publisher= Office of Emergency Management
|archiveurl=https://web.archive.org/web/20070927222903/http://www.ci.fort-collins.co.us/oem/historical-flooding.php |archivedate=2007-09-27}}</ref>
The severity of the flood and its widespread spatial variability surprised [[Meteorologist|meteorologist]]s, and former assistant state climatologist for the state of Colorado, Nolan Doesken, asked for precipitation measurements from private citizens in the area. About 300 responded to his emergency request for data. Said Doesken later, "The results of the data showed that more than 14&nbsp;in. (36&nbsp;cm) of rain fell over southwest Fort Collins, the area where the flood waters originated, while less than 2&nbsp;in. (5&nbsp;cm) of rain fell only 3–4&nbsp;mi (5–6&nbsp;km) east. The enthusiastic interest shown by volunteers and the great value of the data verified the need for such a service, and CoCoRaHS was born."<ref>{{cite web|url=http://www.awwa.org/communications/mainstream/2004/Jul20/Lead02raingaugevolunteers.cfm |title=raingaugevolunteers |website=www.awwa.org }} {{dead link|date=January 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> The program was originally confined to Colorado (the first "Co" in "CoCoRaHS" stood for "Colorado" instead of "Community"), but began expanding to other states during the 2000s.

[[File:2013-06-24 17 39 11 A 4-inch plastic rain gauge typical of those used by the CoCoRaHS program.jpg|thumb|A 4-inch plastic rain gauge, typical of those used by the CoCoRaHS program]]

==Users==
CoCoRaHS is used by a wide variety of organizations and individuals. The [[Earth:National Weather Service|National Weather Service]] (NWS), other meteorologists, hydrologists, [[Social:Emergency management|emergency managers]], city utilities (water supply, water conservation, storm water), transportation departments, insurance adjusters, the USDA, engineers, mosquito control, ranchers and farmers, outdoor & recreation interests, teachers, students, and neighbors in the community are examples of people who use CoCoRaHS data.<ref name="Wilson">{{cite web |url = https://ccsinventory.wilsoncenter.org/#projectId/81 |title = The Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS) |date =  |website = Federal Crowdsourcing and Citizen Science Catalog |publisher = CitizenScience.gov |access-date = 2018-07-08 |archive-date = 2018-07-09 |archive-url = https://web.archive.org/web/20180709065026/https://ccsinventory.wilsoncenter.org/#projectId/81 |url-status = dead }}</ref>

===Other programs===
A similar program, the [[Earth:Significant Weather Observing Program|Significant Weather Observing Program]] (SWOP), was begun independently in around the year 2000 by the National Weather Service Lincoln, Illinois. CoCoRaHS data supplements the more rigorous data from the national program with increased spatial and temporal resolution. Real-time data is also provided by the [[Earth:Citizen Weather Observer Program|Citizen Weather Observer Program]] (CWOP), whose users operate [[Engineering:Weather station|weather station]]s that automatically report over the internet, and which supplements the more rigorous data reported by formal [[Earth:Surface weather observation|surface weather observation]] stations. The earliest and thus critically important for its long-term historical record from respective locations is the Cooperative Observer program of manually recorded daily summaries.

==Sponsors==
The [[Organization:National Oceanic and Atmospheric Administration|National Oceanic and Atmospheric Administration]] (NOAA) and the [[Organization:National Science Foundation|National Science Foundation]] (NSF) are major sponsors of CoCoRaHS and the Bureau of Land Management (BLM) is also a partner.<ref name="Wilson"/> Other organizations have contributed either financially, and/or with supplies and equipment. Many other organizations and individuals have also pitched in time and resources to help keep the network up and running.

==Status==
As of 2015 all fifty states, the District of Columbia, and the Commonwealth of Puerto Rico participate in CoCoRaHS.<ref name=CoCoRaHS-2015-03>{{cite web|title=Welcome to CoCoRaHS!|url=http://www.cocorahs.org/|publisher=CoCoRaHS|archiveurl=https://web.archive.org/web/20150310095655/http://www.cocorahs.org/|archivedate=2015-03-10}}</ref> The CoCoRaHS Canada network began in Manitoba in December 2011 following a massive flood in that province.<ref name=CoCoRaHS-Canada-2014-07>{{cite web|title=About CoCoRaHS Canada|url=http://www.cocorahs.org/Content.aspx?page=about-cocorahs-canada|publisher=CoCoRaHS|archiveurl=https://web.archive.org/web/20140701135921/http://www.cocorahs.org/Content.aspx?page=about-cocorahs-canada|archivedate=2014-07-01}}</ref> As of 2014, the network had expanded to the Canadian provinces of Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland and Labrador, Nova Scotia, Ontario, Prince Edward Island, Quebec, and Saskatchewan.<ref name=CoCoRaHS-Canada-2014-07/> There were over 20,000 participants as of March 2015.<ref name="Wilson"/>

==See also==
* [[Organization:Skywarn|Skywarn]]
* [[Organization:Safecast|Safecast]]

==References==
{{reflist|2}}

==External links==
* [https://web.archive.org/web/20150310095655/http://www.cocorahs.org/ CoCoRaHS website] and [http://cocorahs.blogspot.com/ blog]
* [https://twitter.com/cocorahs/ Twitter profile]
* [https://www.facebook.com/CoCoRaHS Facebook page]
* [http://www.nws.noaa.gov/om/coop/ NOAA Cooperative Weather Observer Program]

[[Category:Meteorological data and networks]]

{{Sourceattribution|Community Collaborative Rain, Hail and Snow Network}}