Editing Northern Hemisphere

{{Short description|Half of Earth that is north of the Equator}}
{{About|the northern half of planet Earth|use of the term describing astronomical observations|Northern celestial hemisphere}}
[[File: Northern Hemisphere LamAz.png|thumb|right|Northern Hemisphere from above the [[North Pole]]]]
The '''Northern Hemisphere''' is the half of [[Earth]] that is [[north]] of the [[equator]]. For other planets in the [[Solar System]], north is defined by humans as being in the same [[celestial sphere|celestial hemisphere]] relative to the [[invariable plane]] of the Solar System as Earth's [[North Pole]].<ref name="report">{{Cite journal|doi=10.1007/s10569-010-9320-4|title=Report of the IAU Working Group on Cartographic Coordinates and Rotational Elements: 2009|url=http://astropedia.astrogeology.usgs.gov/alfresco/d/d/workspace/SpacesStore/28fd9e81-1964-44d6-a58b-fbbf61e64e15/WGCCRE2009reprint.pdf|journal=Celestial Mechanics and Dynamical Astronomy|volume=109|issue=2|pages=101–135|year=2010|last1=Archinal|first1=Brent A.|last2=A'Hearn|first2=Michael F.|last3=Bowell|first3=Edward G.|last4=Conrad|first4=Albert R.|last5=Consolmagno|first5=Guy J.|display-authors=5|last6=Courtin|first6=Régis|last7=Fukushima|first7=Toshio|last8=Hestroffer|first8=Daniel|last9=Hilton|first9=James L.|last10=Krasinsky|first10=George A.|last11=Neumann|first11=Gregory A.|last12=Oberst|first12=Jürgen|last13=Seidelmann|first13=P. Kenneth|last14=Stooke|first14=Philip J.|last15=Tholen|first15=David J.|last16=Thomas|first16=Paul C.|last17=Williams|first17=Iwan P.|bibcode=2011CeMDA.109..101A|s2cid=189842666|access-date=2018-09-26|archive-url=https://web.archive.org/web/20160304065344/http://astropedia.astrogeology.usgs.gov/alfresco/d/d/workspace/SpacesStore/28fd9e81-1964-44d6-a58b-fbbf61e64e15/WGCCRE2009reprint.pdf|archive-date=2016-03-04|url-status=dead}}</ref>

Due to Earth's [[axial tilt]] of 23.439281°, there is a seasonal variation in the lengths of the day and night. There is also a seasonal variation in temperatures, which lags the variation in day and night. Conventionally, [[winter]] in the Northern Hemisphere is taken as the period from the [[December solstice]] (typically December 21 [[UTC]]) to the [[March equinox]] (typically March 20 UTC), while [[summer]] is taken as the period from the [[June solstice]] through to the [[September equinox]] (typically on 23 September UTC). The dates vary each year due to the difference between the [[calendar year]] and the [[Year#Astronomical years|astronomical year]]. Within the Northern Hemisphere, oceanic currents can change the weather patterns that affect many factors within the north coast. Such events include [[El Niño–Southern Oscillation]].

[[Trade winds]] blow from east to west just above the equator. The winds pull surface water with them, creating currents, which flow westward due to the [[Coriolis effect]]. The currents then bend to the right, heading north. At about 30 degrees north latitude, a different set of winds, the [[westerlies]], push the currents back to the east, producing a closed clockwise loop.<ref>{{Cite web|date=2019-07-01|title=Ocean Currents|url=https://education.nationalgeographic.org/resource/ocean-currents/|access-date=2020-10-16|website=National Geographic Society|language=en|archive-date=2021-11-20|archive-url=https://web.archive.org/web/20211120202501/https://www.nationalgeographic.org/encyclopedia/ocean-currents/|url-status=live}}</ref>

Its surface is 60.7% water, compared with 80.9% water in the case of the [[Southern Hemisphere]], and it contains 67.3% of Earth's land.<ref>{{cite book|title=Life on Earth: A – G.. 1|date=2002|publisher=[[ABC-CLIO]]|isbn=9781576072868|page=528|url=https://books.google.com/books?id=iVEWPg8vnxgC&q=southern+hemisphere+contains+%25+land&pg=PA528|access-date=8 September 2016|archive-date=22 January 2023|archive-url=https://web.archive.org/web/20230122160606/https://books.google.com/books?id=iVEWPg8vnxgC&q=southern+hemisphere+contains+%25+land&pg=PA528|url-status=live}}</ref> The continents of [[North America]] and mainland [[Eurasia]] are located entirely in the Northern Hemisphere, together with about two-thirds of [[Africa]] and a small part of [[South America]].

==Geography and climate==
During the 2.5 million years of the [[Pleistocene]], numerous cold phases called [[Glacial period|glacials]] ([[Quaternary glaciation|Quaternary ice age]]), or significant advances of continental ice sheets, in [[Europe]] and [[North America]], occurred at intervals of approximately 40,000 to 100,000 years. The long glacial periods were separated by more temperate and shorter [[interglacial]]s which lasted about 10,000–15,000 years. The last cold episode of the [[last glacial period]] ended about 10,000 years ago.<ref>{{cite magazine|url=https://www.nationalgeographic.com/science/prehistoric-world/quaternary|title=Quaternary Period|magazine=National Geographic|date=2017-01-06|access-date=2022-05-06|archive-date=2020-11-29|archive-url=https://web.archive.org/web/20201129042714/https://www.nationalgeographic.com/science/prehistoric-world/quaternary/|url-status=dead}}</ref> Earth is currently in an interglacial period of [[Quaternary|the Quaternary]], called the [[Holocene]].<ref>{{cite news |title=How long can we expect the present Interglacial period to last? |url=https://www.usgs.gov/faqs/how-long-can-we-expect-present-interglacial-period-last |work=U.S. Department of the Interior |access-date=2022-05-06 |archive-date=2022-07-26 |archive-url=https://web.archive.org/web/20220726044340/http://www.usgs.gov/faqs/how-long-can-we-expect-present-interglacial-period-last |url-status=live }}</ref> The glaciations that occurred during the glacial period covered many areas of the Northern Hemisphere.

[[File:Northern icesheet hg.png|thumb|Northern hemisphere glaciation during the last [[ice age]]s. The setup of 3 to 4 kilometer thick ice sheets caused a [[sea level rise|sea level lowering]] of about 120&nbsp;m.]]
The [[Arctic]] is a region around the [[North Pole]] (90° [[latitude]]). Its climate is characterized by cold winters and cool summers. Precipitation mostly comes in the form of snow. Areas inside the [[Arctic Circle]] (66°34′ latitude) experience some days in summer when the Sun never sets, and some days during the winter when it never rises. The duration of these phases varies from one day for locations right on the Arctic Circle to several months near the Pole, which is the middle of the Northern Hemisphere. Between the Arctic Circle and the [[Tropic of Cancer]] (23°26′ latitude) lies the [[Northern temperate zone]]. The changes in these regions between summer and winter are generally mild, rather than extreme hot or cold. However, a temperate climate can have very unpredictable weather.

[[Tropics|Tropical]] regions (between the Tropic of Cancer and the Equator, 0° latitude) are generally hot all year round and tend to experience a [[Wet season|rainy season]] during the summer months, and a [[dry season]] during the winter months.

[[File:Snow covered mountains in Mount Robson (Unsplash).jpg|thumb|[[Canadian Rockies]] in North America]]
In the Northern Hemisphere, objects moving across or above the surface of the Earth tend to turn to the right because of the [[Coriolis effect]]. As a result, large-scale horizontal flows of air or water tend to form clockwise-turning [[Ocean gyre|gyres]].<ref name= USDoC>{{Cite web|last=US Department of Commerce|first=National Oceanic and Atmospheric Administration|title=Boundary Currents – Currents: NOAA's National Ocean Service Education|url=https://oceanservice.noaa.gov/education/tutorial_currents/04currents3.html|access-date=2020-07-31|website=oceanservice.noaa.gov|language=EN-US|archive-date=2010-05-15|archive-url=https://web.archive.org/web/20100515015346/https://oceanservice.noaa.gov/education/tutorial_currents/04currents3.html|url-status=live}}</ref> These are best seen in ocean circulation patterns in the [[Atlantic Ocean|North Atlantic]] and [[Pacific Ocean|North Pacific]] oceans.<ref name= USDoC/> Within the Northern Hemisphere, oceanic currents can change the weather patterns that affect many factors within the north coast.<ref>{{cite web |url= https://oceanexplorer.noaa.gov/facts/climate.html|title=How does the ocean affect climate and weather on land? |author=<!--Not stated--> |date= |website=NOAA Ocean Exploration |publisher=U.S. Department of Commerce |access-date=21 November 2023 |quote=}}</ref> For the same reason, flows of air down toward the northern surface of the Earth tend to spread across the surface in a clockwise pattern. Thus, clockwise air circulation is characteristic of [[high pressure]] weather cells in the Northern Hemisphere. Conversely, air rising from the northern surface of the Earth (creating a region of low pressure) tends to draw air toward it in a counterclockwise pattern. [[Tropical cyclone|Hurricanes]] and [[tropical cyclone|tropical storms]] (massive low-pressure systems) spin counterclockwise in the Northern Hemisphere.<ref>{{Cite web|title=Hurricanes: Science and Society: Primary Circulation|url=http://www.hurricanescience.org/science/science/primarycirculation/|access-date=2021-08-11|website=www.hurricanescience.org|archive-date=2010-12-28|archive-url=https://web.archive.org/web/20101228015456/http://www.hurricanescience.org/science/science/primarycirculation/|url-status=live}}</ref>

The shadow of a sundial moves clockwise on latitudes north of the [[subsolar point]] and anticlockwise to the south. During the day at these latitudes, the Sun tends to rise to its maximum at a southerly position. Between the Tropic of Cancer and the Equator, the Sun can be seen to the north, directly overhead, or to the south at noon, depending on the time of year. In the Southern Hemisphere, the midday Sun is predominantly in the north.

When viewed from the Northern Hemisphere, the [[Moon]] appears inverted compared to a view from the Southern Hemisphere.<ref>{{cite web|url=http://curious.astro.cornell.edu/our-solar-system/46-our-solar-system/the-moon/observing-the-moon/135-does-the-moon-look-different-in-the-northern-and-southern-hemispheres-beginner|title=Does the Moon look different in the northern and southern hemispheres? (Beginner) – Curious About Astronomy? Ask an Astronomer|author=Laura Spitler|work=cornell.edu|access-date=10 November 2015|archive-date=4 November 2015|archive-url=https://web.archive.org/web/20151104012834/http://curious.astro.cornell.edu/our-solar-system/46-our-solar-system/the-moon/observing-the-moon/135-does-the-moon-look-different-in-the-northern-and-southern-hemispheres-beginner|url-status=live}}</ref><ref>{{cite web|title=Perspective of the Moon from the Northern and Southern Hemispheres|url=http://epod.usra.edu/blog/2011/09/perspective-of-the-moon-from-the-northern-and-southern-hemispheres.html|access-date=22 October 2013|archive-url=https://web.archive.org/web/20170909070809/http://epod.usra.edu/blog/2011/09/perspective-of-the-moon-from-the-northern-and-southern-hemispheres.html|archive-date=9 September 2017|url-status=dead}}</ref> The North Pole faces away from the [[Galactic Center]] of the [[Milky Way]]. This results in the Milky Way being sparser and dimmer in the Northern Hemisphere compared to the Southern Hemisphere, making the Northern Hemisphere more suitable for deep-space observation, as it is not "blinded" by the Milky Way.{{citation needed|date=August 2015}}

==Demographics==
As of 2015, the Northern Hemisphere is home to approximately 6.4 billion people, which is around 87.0% of the Earth's total human population of 7.3 billion people.<ref>Calculated from World Population Yearbook 2019(in thousands)

World total population: 7,359,970

Northern Hemisphere population: 6,405,030	87.0%

Southern Hemisphere population: 954,940	13.0%

Note 1) If there is no data for 2019, the latest data was used.

Note 2) Countries with land that straddles the equator are divided into half populations in each of the Northern and Southern Hemispheres.</ref><ref>{{cite web|url=http://www.businessinsider.com/90-of-people-live-in-the-northern-hemisphere-2012-5|title=90% Of People Live In The Northern Hemisphere – Business Insider|date=4 May 2012|work=Business Insider|access-date=10 November 2015|archive-date=19 January 2018|archive-url=https://web.archive.org/web/20180119181108/http://www.businessinsider.com/90-of-people-live-in-the-northern-hemisphere-2012-5|url-status=live}}</ref><ref>{{cite web|url=http://find.galegroup.com/gic/infomark.do?&contentSet=EBKS&idigest=fb720fd31d9036c1ed2d1f3a0500fcc2&type=retrieve&tabID=T001&prodId=GIC&docId=CX3403900089&source=gale&userGroupName=itsbtrial&version=1.0|title=GIC – Article|work=galegroup.com|access-date=10 November 2015|archive-date=18 April 2016|archive-url=https://web.archive.org/web/20160418075026/http://find.galegroup.com/gic/infomark.do?&contentSet=EBKS&idigest=fb720fd31d9036c1ed2d1f3a0500fcc2&type=retrieve&tabID=T001&prodId=GIC&docId=CX3403900089&source=gale&userGroupName=itsbtrial&version=1.0|url-status=live}}</ref> This Northern Hemisphere contains areas such as northern europe and [[Northern America]].

== List of continents, countries or territories, and oceans in the Northern Hemisphere ==
{| class="wikitable" style="font-size:90%"
! colspan="4" | Continents
|-
! width=25%|[[Africa]]
! width=25%|[[Asia]]
! width=25%|[[Americas]]
! width=25%|[[Europe]]
|-
| About two-thirds, from north of [[Libreville]] in [[Gabon]] in the west to south of [[Mogadishu]] in [[Somalia]] in the east. || The entire continental mainland. Part of [[Indonesia]], and [[Atolls of the Maldives|24 out of 26 atolls]] of [[Maldives]] in the [[Indian Ocean]], are also in the Northern Hemisphere. || All of [[North America]], [[Central America]], and the [[Caribbean]] islands. About one-fifth of [[South America]], from north of [[Quito]] in [[Ecuador]] in the west to north of the [[Amazon River]] mouth in [[Brazil]] in the east. ||Entirely in the Northern Hemisphere{{NoteTag|name=overseas-europe}}
|-
! colspan="4" | Countries or Territories
|-
! [[Africa]]
! [[Asia]]
! [[Americas]]
! [[Europe]]{{NoteTag|name=overseas-europe|The continent itself is entirely within the Northern Hemisphere. However, some overseas territories of the countries of [[France]], [[Norway]] and the [[United Kingdom]] are in the Southern Hemisphere.}}
|-
|valign=top|
;<big>Entirely</big>
* [[Algeria]]
* [[Benin]]
* [[Burkina Faso]]
* [[Cameroon]]
* [[Cape Verde]]
* [[Central African Republic]]
* [[Chad]]
* [[Djibouti]]
* [[Egypt]]
* [[Eritrea]]
* [[Ethiopia]]
* [[Gambia]]
* [[Ghana]]
* [[Guinea]]
* [[Guinea-Bissau]]
* [[Ivory Coast]]
* [[Liberia]]
* [[Libya]]
* [[Mali]]
* [[Mauritania]]
* [[Morocco]]
* [[Niger]]
* [[Nigeria]]
* [[Senegal]]
* [[Sierra Leone]]
* [[South Sudan]]
* [[Sudan]]
* [[Togo]]
* [[Tunisia]]

;<big>Mostly</big>
* [[Equatorial Guinea]]
* [[Kenya]]
* [[São Tomé and Príncipe]]
* [[Somalia]]
* [[Uganda]]

;<big>Entirely</big>
* [[Democratic Republic of the Congo]]
* [[Gabon]]
* [[Republic of the Congo]]
| valign=top|
;<big>Entirely</big>
* [[Afghanistan]]
* [[Armenia]]
* [[Azerbaijan]]
* [[Bahrain]]
* [[Bangladesh]]
* [[Bhutan]]
* [[Brunei]]
* [[Cambodia]]
* [[China]]
* [[Cyprus]]
* [[Georgia (country)|Georgia]]
* [[India]]
* [[Iran]]
* [[Iraq]]
* [[Israel]]
* [[Japan]]
* [[Jordan]]
* [[Kazakhstan]]
* [[Kuwait]]
* [[Kyrgyzstan]]
* [[Laos]]
* [[Lebanon]]
* [[Malaysia]]
* [[Mongolia]]
* [[Myanmar]]
* [[Nepal]]
* [[North Korea]]
* [[Oman]]
* [[Pakistan]]
* [[Palestine]]
* [[Philippines]]
* [[Qatar]]
* [[Saudi Arabia]]
* [[Singapore]]
* [[South Korea]]
* [[Sri Lanka]]
* [[Syria]]
* [[Tajikistan]]
* [[Thailand]]
* [[Turkey]]
* [[Turkmenistan]]
* [[United Arab Emirates]]
* [[Uzbekistan]]
* [[Vietnam]]
* [[Yemen]]

;<big>Mostly</big>
* [[Maldives]]

;<big>Partly</big>
* [[Indonesia]] 
|valign=top|
;<big>Entirely</big>
* [[Belize]]
* [[Canada]]
* [[Costa Rica]]
* [[El Salvador]]
* [[Guatemala]]
* [[Guyana]]
* [[Honduras]]
* [[Mexico]]
* [[Nicaragua]]
* [[Panama]]
* [[Suriname]]
* [[Venezuela]]
* [[United States]]

;<big>Mostly</big>
* [[Colombia]]

;<big>Partly</big>
* [[Brazil]]
* [[Ecuador]]
|valign=top|
;<big>Entirely</big>
* [[Albania]]
* [[Andorra]]
* [[Austria]]
* [[Belarus]]
* [[Belgium]]
* [[Bosnia and Herzegovina]]
* [[Bulgaria]]
* [[Croatia]]
* [[Czech Republic]]
* [[Denmark]]
* [[Estonia]]
* [[Finland]]
* [[Germany]]
* [[Greece]]
* [[Hungary]]
* [[Iceland]]
* [[Ireland]]
* [[Italy]]
* [[Latvia]]
* [[Liechtenstein]]
* [[Lithuania]]
* [[Luxembourg]]
* [[Malta]]
* [[Moldova]]
* [[Monaco]]
* [[Montenegro]]
* [[Netherlands]]
* [[North Macedonia]]
* [[Poland]]
* [[Portugal]]
* [[Romania]]
* [[Russia]]
* [[San Marino]]
* [[Serbia]]
* [[Slovakia]]
* [[Slovenia]]
* [[Spain]]
* [[Sweden]]
* [[Switzerland]]
* [[Ukraine]]
* [[Vatican City]]

;<big>Mostly</big>
* [[France]]
* [[Norway]]
* [[United Kingdom]]
|-
! colspan="4" | Oceans
|-
! [[Arctic Ocean|Arctic]]
! [[Atlantic]]
! [[Indian Ocean|Indian]]
! [[Pacific]]
|-
|valign=top|
;<big>Entirely</big>
* [[Jan Mayen]], [[Norway]]
* [[Kaffeklubben Island]], [[Denmark]]
* [[Queen Elizabeth Islands]], [[Canada]]
* [[Russian Arctic islands]], [[Russia]]
* [[Svalbard]] ([[Norway]])
|valign=top|
;<big>Entirely</big>
* [[Akrotiri and Dhekelia]], [[British Overseas Territories]]
* [[Anguilla]], [[British Overseas Territories]]
* [[Antigua and Barbuda]]
* [[Aruba]], [[Kingdom of the Netherlands]]
* [[Bahamas]]
* [[Bailiwick of Guernsey|Guernsey]], [[Crown Dependencies|a Crown Dependency]]
* [[Bailiwick of Jersey|Jersey]], [[Crown Dependencies|a Crown Dependency]]
* [[Barbados]]
* [[Belize]]
* [[Bermuda]], [[British Overseas Territories]]
* [[Bioko]] ([[Equatorial Guinea]])
* [[Bonaire]], [[Kingdom of the Netherlands]]
* [[British Virgin Islands]], [[British Overseas Territories]]
* [[Cape Verde]]
* [[Cayman Islands]], [[British Overseas Territories]]
* [[Curaçao]], [[Kingdom of the Netherlands]]
* [[Cyprus]]
* [[Dominica]]
* [[Dominican Republic]]
* [[Faroe Islands]], [[Kingdom of Denmark]]
* [[Greenland]], [[Kingdom of Denmark]]
* [[Grenada]]
* [[Guyana]]
* [[Haiti]]
* [[Iceland]]
* [[Isle of Man]], [[Crown Dependencies|a Crown Dependency]]
* [[Jamaica]]
* [[Montserrat]], [[British Overseas Territories]]
* [[Puerto Rico]], [[Territories of the United States]]
* [[Saba (island)|Saba]], [[Kingdom of the Netherlands]]
* [[Saint Kitts and Nevis]]
* [[Saint Lucia]]
* [[Saint Martin (island)|Saint Martin]], [[Overseas Collectivity|Overseas Collectivity of France]]
* [[Saint Vincent and the Grenadines]]
* [[Sint Eustatius]], [[Kingdom of the Netherlands]]
* [[Sint Maarten]], [[Kingdom of the Netherlands]]
* [[Trinidad and Tobago]]
* [[Turks and Caicos Islands]], [[British Overseas Territories]]
* [[U.S Virgin Islands]], [[Territories of the United States]]

;<big>Mostly</big>
* [[São Tomé and Príncipe]] 
|valign=top|
;<big>Entirely</big>
* [[Bahrain]]
* [[Andaman Islands]] ([[India]])
* [[Sri Lanka]]
* [[Socotra]] ([[Yemen]])

;<big>Mostly</big>
* [[Sumatra]] ([[Indonesia]])
* [[Maldives]] 
* [[Singapore]]
|valign=top|
;<big>Entirely</big>
* [[Guam]], [[Territories of the United States]]
* [[Hainan]] ([[China]])
* [[Hawaii]], ([[U.S. state]])
* [[Japan]]
* [[Northern Mariana Islands]], [[Territories of the United States]]
* [[Palau]]
* [[Philippines]]
* [[Formosa]] ([[Taiwan]])

;<big>Mostly</big>
* [[Borneo]], ([[Brunei]], and [[Malaysia]]) or [[Kalimantan]] in [[Indonesia]]
* [[Maluku Islands]] ([[Indonesia]])

;<big>Partly</big>
* [[Kiribati]]
* [[Sulawesi]] ([[Indonesia]])
* [[Western New Guinea]] ([[Indonesia]])
|-
|}

==See also==
* [[Southern Hemisphere]]
* [[Hemispheres of Earth]]
* [[Africa]]
* [[Asia]]
* [[Americas]]
* [[Europe]]
* [[Arctic Ocean]]
* [[Atlantic Ocean]]
* [[Indian Ocean]]
* [[Pacific Ocean]]
* [[North–South divide (disambiguation)]]
* [[Global North]]

==Notes==
{{reflist|group=note}}

==References==
{{reflist}}

{{Commons category}}

{{Regions of the world}}
{{Authority control}}

[[Category:Northern Hemisphere| ]]
[[Category:Hemispheres of Earth]]