Editing Labrador Current (section)

== Freshwater origins ==
The Labrador Current has an average annual velocity of 20 cm/s and is formed from very cold water that is around 1.5˚C from the Arctic through Baffin Island, Canada, and Western [[Greenland]]. These waters come together in the [[Labrador Sea]]. The Labrador Sea is affected by seasonality and will experience greater freshwater imports during the late spring and early summer with riverine runoff and glacial melt.<ref>{{Cite journal |last1=Li |first1=Gang |last2=Piper |first2=David J. W. |date=2015-01-01 |title=The influence of meltwater on the Labrador Current in Heinrich event 1 and the Younger Dryas |url=https://www.sciencedirect.com/science/article/pii/S0277379114004089 |journal=Quaternary Science Reviews |language=en |volume=107 |pages=129–137 |doi=10.1016/j.quascirev.2014.10.021 |bibcode=2015QSRv..107..129L |issn=0277-3791|url-access=subscription }}</ref>

The ocean circulation in the subpolar regions in the North Atlantic have seasonal variations due to the cold, freshwater Labrador Current and the warm, salty [[North Atlantic Current]], as well as with changing surface winds, heat flux, and ice melting and formation.<ref>{{Cite journal |last1=Han |first1=Guoqi |last2=Lu |first2=Zhaoshi |last3=Wang |first3=Zeliang |last4=Helbig |first4=James |last5=Chen |first5=Nancy |last6=de Young |first6=Brad |date=2008-10-17 |title=Seasonal variability of the Labrador Current and shelf circulation off Newfoundland |journal=Journal of Geophysical Research |language=en |volume=113 |issue=C10 |pages=C10013 |doi=10.1029/2007JC004376 |bibcode=2008JGRC..11310013H |issn=0148-0227|doi-access=free }}</ref> There are two parts that make up the Labrador Current. The first part is baroclinic, meaning that the density depends on temperature and pressure, and is buoyancy-driven due to the amount of freshwater that is imported from the North. The second part of the Labrador Current is deeper and is barotropic, meaning the density is only dependent on pressure, and reaches a depth of about 2500 meters.<ref>{{Cite book |last=Thorpe |first=Steve A. |title=Ocean Currents |publisher=Elsevier |year=2009 |isbn=978-0-08-096486-7 |edition=2nd}}</ref>

[[Baffin Bay]] and the [[Hudson Strait]] are the largest freshwater contributors to the Labrador Current.<ref>{{Cite journal |last1=Mertz |first1=G. |last2=Narayanan |first2=S. |last3=Helbig |first3=J. |date=1993 |title=The freshwater transport of the labrador current |journal=Atmosphere-Ocean |language=en |volume=31 |issue=2 |pages=281–295 |doi=10.1080/07055900.1993.9649472 |issn=0705-5900|doi-access=free |bibcode=1993AtO....31..281M }}</ref> The Hudson Strait is a narrow channel that is about 400 km long and is the opening to the Hudson Bay System, which is connected to the Labrador Sea, and contributes 50% of the freshwater transport of the Labrador Current. Hudson Bay is covered in ice in the winter and is ice-free in the summer. Hudson Bay has 42 rivers, contributing to the river runoff. The Labrador Current is made up of the Hudson Strait outflow, or the southeast flow, that meets with the [[Davis Strait]] and the [[West Greenland Current]].<ref>{{Cite journal |last1=Straneo |first1=Fiammetta |last2=Saucier |first2=François |date=2008-08-01 |title=The outflow from Hudson Strait and its contribution to the Labrador Current |url=https://www.sciencedirect.com/science/article/pii/S0967063708000642 |journal=Deep Sea Research Part I: Oceanographic Research Papers |language=en |volume=55 |issue=8 |pages=926–946 |doi=10.1016/j.dsr.2008.03.012 |bibcode=2008DSRI...55..926S |hdl=1912/2424 |s2cid=129009304 |issn=0967-0637|hdl-access=free }}</ref> This current then flows south, down through Newfoundland and [[Flemish Cap]] and along the continental shelf break. Part of this current moves westward along the continental slope near Nova Scotia, eventually reaching north of the [[Gulf Stream]], this is called the ''Slope Water Current''. The southward flow joins in the subpolar circulation, forming the narrow, western subpolar gyre in the North Atlantic. The current interacts with the Gulf Stream and the [[North Atlantic Current]] forming the western boundary current that makes up this gyre.<ref>{{Cite book |last=Talley, Pickard, Emery, Swift |first=Lynne D., George L., William J., James H. |title=Descriptive Physical Oceanography: An Introduction |publisher=Elsevier |year=2011 |isbn=978-0-7506-4552-2 |edition=6th}}</ref>