Editing Delaware Valley (section)

==Geography and population==
{{See also|Geography of Pennsylvania|Geography of New Jersey|Geography of Delaware}}
[[File:Delaware river basin map.png|thumb|The drainage basin of the [[Delaware River]]]]
The Philadelphia metropolitan area is geographically associated and proximate to the [[Delaware River]] and its three primary tributaries, the [[Schuylkill River]], [[Lehigh River]], and  [[Brandywine Creek (Christina River tributary)|Brandywine Creek]].

[[Federal government of the United States|U.S. government]] agencies have reached various definitions of metropolitan Philadelphia. The [[Office of Management and Budget]] (OMB) defines [[metropolitan statistical area]] (MSAs), which are regions with relatively high population densities at their cores and close economic ties throughout their respective areas. MSAs are further combined into [[combined statistical areas]] (CSAs), reflecting commuting patterns. Neither is a formal administrative division.

===Metropolitan statistical area (MSA)===
{{US Census population
|1820= 171430
|1830= 228203
|1840= 305278
|1850= 467053
|1860= 636029
|1870= 841230
|1880= 1062677
|1890= 1391157
|1900= 1892496
|1910= 2268209
|1920= 2714271
|1930= 3137040
|1940= 3299637
|1950= 3671048
|1960= 4757462
|1970= 5317407
|1980= 5240039
|1990= 5435468
|2000= 5687147
|2010= 5965343
|2020= 6245051
|estimate= 6241164
|estyear= 2022
|footnote=[https://www.census.gov/programs-surveys/decennial-census.html U.S. Decennial Census]
}}

As of the [[2020 United States census|2020 U.S. census]], the Philadelphia-Camden-Wilmington Metropolitan Statistical Area is the [[List of Metropolitan Statistical Areas|seventh-largest MSA]] in the nation with 6,245,051 people.<ref>{{cite web |title=Annual Estimates of the Resident Population: April 1, 2010 to July 1, 2016 |url=https://factfinder.census.gov/bkmk/table/1.0/en/PEP/2016/PEPANNRES/0100000US.31000.001 |url-status=dead |archive-url=https://archive.today/20200214000412/https://factfinder.census.gov/bkmk/table/1.0/en/PEP/2016/PEPANNRES/0100000US.31000.001 |archive-date=February 14, 2020 |access-date=December 30, 2017 |publisher=United States Census Bureau}}</ref> The MSA includes:
* Camden, NJ Metropolitan Division
** [[Burlington County, New Jersey|Burlington County (NJ)]]
** [[Camden County, New Jersey|Camden County (NJ)]]
** [[Gloucester County, New Jersey|Gloucester County (NJ)]]
* Philadelphia, PA Metropolitan Division
** [[Bucks County, Pennsylvania|Bucks County (PA)]]
** [[Chester County, Pennsylvania|Chester County (PA)]]
** [[Delaware County, Pennsylvania|Delaware County (PA)]]
** [[Montgomery County, Pennsylvania|Montgomery County (PA)]]
** [[Philadelphia County, Pennsylvania|Philadelphia County (PA)]]
* Wilmington, DE-NJ Metropolitan Division
** [[New Castle County, Delaware|New Castle County (DE)]]
** [[Salem County, New Jersey|Salem County (NJ)]]
** [[Cecil County, Maryland|Cecil County (MD)]]
{| class="wikitable sortable"
![[List of counties in Pennsylvania|County]]
!2021 Estimate
!2020 Census
!Change
!Area
!Density
|-
|[[Philadelphia County, Pennsylvania|Philadelphia County]]
| {{change|invert=on|1576251|1603797}}
|{{convert|134.28|sqmi|abbr=on}}
|{{Pop density|1576251|134.28|sqmi|km2|prec=0}}
|-
|[[Montgomery County, Pennsylvania|Montgomery County]]
| {{change|invert=on|860578|856553}}
|{{convert|483|sqmi|abbr=on}}
|{{Pop density|860578|483|sqmi|km2|prec=0}}
|-
|[[Bucks County, Pennsylvania|Bucks County]]
| {{change|invert=on|646098|646538}}
|{{convert|604|sqmi|abbr=on}}
|{{Pop density|646098|604|sqmi|km2|prec=0}}
|-
|[[Delaware County, Pennsylvania|Delaware County]]
| {{change|invert=on|573849|576830}}
|{{convert|184|sqmi|abbr=on}}
|{{Pop density|573849|184|sqmi|km2|prec=0}}
|-
|[[New Castle County, Delaware|New Castle County]]
| {{change|invert=on|571708|570719}}
|{{convert|426|sqmi|abbr=on}}
|{{Pop density|571708|426|sqmi|km2|prec=0}}
|-
|[[Chester County, Pennsylvania|Chester County]]
| {{change|invert=on|538649|534413}}
|{{convert|751|sqmi|abbr=on}}
|{{Pop density|538649|751|sqmi|km2|prec=0}}
|-
|[[Camden County, New Jersey|Camden County]]
| {{change|invert=on|523771|523485}}
|{{convert|221.26|sqmi|abbr=on}}
|{{Pop density|523771|221.26|sqmi|km2|prec=0}}
|-
|[[Burlington County, New Jersey|Burlington County]]
| {{change|invert=on|464269|461860}}
|{{convert|798.58|sqmi|abbr=on}}
|{{Pop density|464269|798.58|sqmi|km2|prec=0}}
|-
|[[Gloucester County, New Jersey|Gloucester County]]
| {{change|invert=on|304477|302294}}
|{{convert|322|sqmi|abbr=on}}
|{{Pop density|304477|322|sqmi|km2|prec=0}}
|-
|[[Salem County, New Jersey|Salem County]]
| {{change|invert=on|65046|64837}}
|{{convert|331.9|sqmi|abbr=on}}
|{{Pop density|65046|331.9|sqmi|km2|prec=0}}
|-
|[[Cecil County, Maryland|Cecil County]]
| {{change|invert=on|103725|104870}}
|{{convert|418|sqmi|abbr=on}}
|{{Pop density|104870|418|sqmi|km2|prec=0}}

|-
|- class="sortbottom" style="background:#fbfbbb"
|'''Total MSA Population'''
| {{change|invert=on|6228601|6245051|bgcolour=#fbfbbb}}
|{{convert|4602.02|sqmi|abbr=on}}
|{{Pop density|6228601|4602.02|sqmi|km2|prec=0}}
|}

===Combined statistical area (CSA)===
As of 2020, the Philadelphia–Reading–Camden, PA-NJ-DE-MD CSA is the nation's ninth-largest [[combined statistical area]] with a population of 7,379,700. '''Philadelphia-Reading-Camden Combined Statistical Area''' includes:
* Philadelphia-Camden-Wilmington MSA (11 counties, as defined above)
* [[Berks County, Pennsylvania]], comprising the Reading, PA MSA
* [[Atlantic County, New Jersey]], comprising the Atlantic City-Hammonton, NJ MSA
* [[Cape May County, New Jersey]], comprising the Ocean City, NJ MSA
* [[Cumberland County, New Jersey]], comprising the Vineland-Bridgeton, NJ MSA
* [[Kent County, Delaware]], comprising the Dover, DE MSA
{| class="wikitable sortable"
![[List of counties in Pennsylvania|County]]
!2021 Estimate
!2020 Census
!Change
!Area
!Density
|-
|[[Berks County, Pennsylvania|Berks County]]
| {{change|invert=on|429342|428849}}
|{{convert|857|sqmi|abbr=on}}
|{{Pop density|429342|857|sqmi|km2|prec=0}}
|-
|[[Atlantic County, New Jersey|Atlantic County]]
| {{change|invert=on|274966|274534}}
|{{convert|555.7|sqmi|abbr=on}}
|{{Pop density|274966|555.7|sqmi|km2|prec=0}}
|-
|[[Kent County, Delaware|Kent County]]
| {{change|invert=on|184149|181851}}
|{{convert|586|sqmi|abbr=on}}
|{{Pop density|184149|586|sqmi|km2|prec=0}}
|-
|[[Cumberland County, New Jersey|Cumberland County]]
| {{change|invert=on|153627|154152}}
|{{convert|483.7|sqmi|abbr=on}}
|{{Pop density|153627|483.7|sqmi|km2|prec=0}}
|-
|[[Cape May County, New Jersey|Cape May County]]
| {{change|invert=on|95661|95263}}
|{{convert|251.42|sqmi|abbr=on}}
|{{Pop density|95661|251.42|sqmi|km2|prec=0}}
|-
|- class="sortbottom" style="background:#fbfbbb"
|'''Total CSA Population'''
| {{change|invert=on|7366346|7379700|bgcolour=#fbfbbb}}
|{{convert|7335.84|sqmi|abbr=on}}
|{{Pop density|7366346|7335.84|sqmi|km2|prec=0}}
|}[[File:Boswash.png|thumb|The Philadelphia metropolitan area is part of the [[Northeast megalopolis]], the second-most highly populated [[Megaregions of the United States|megaregion]] of the U.S. with 52.3 million residents.]]
===Statistical history===
When metropolitan areas were originally defined in 1950, most of this urban area was split between four metropolitan areas, or standard metropolitan areas, as they were then called. The Philadelphia SMA included [[Philadelphia County, Pennsylvania|Philadelphia]], [[Bucks County, Pennsylvania|Bucks]], [[Chester County, Pennsylvania|Chester]], [[Delaware County, Pennsylvania|Delaware]], and [[Montgomery County, Pennsylvania|Montgomery]] counties in [[Pennsylvania]], and [[Burlington County, New Jersey|Burlington]], [[Camden County, New Jersey|Camden]], and [[Gloucester County, New Jersey|Gloucester]] counties in [[South Jersey]]. The Wilmington SMA included [[New Castle County, Delaware|New Castle County]] in [[Delaware]] and [[Salem County, New Jersey|Salem County]] in South Jersey. [[Berks County, Pennsylvania|Berks County]] was designated as the Reading SMA and [[Atlantic County, New Jersey]] was the Atlantic City SMA.

In 1960, [[Cecil County, Maryland]] was added to what was now the Wilmington Standard Metropolitan Statistical Area (SMSA). In 1980, [[Cumberland County, New Jersey]] was defined as the Vineland-Millville-Bridgeton SMSA.

In 1990, the Philadelphia, Wilmington and Vineland-Millville-Bridgeton SMSAs were merged with the Trenton SMSA to form the '''Philadelphia-Wilmington-Trenton Consolidated Metropolitan Statistical Area.''' At the same time, [[Cape May County, New Jersey]] was added to the Atlantic City SMSA. The "Philadelphia-Wilmington-Trenton" became obsolete one census later when [[Trenton, New Jersey]] was moved to the New York-Newark-Bridgeport CSA. The Philadelphia-Wilmington-Vineland CSA included the Philadelphia-Wilmington-Camden MSA and the Vineland-Millville-Bridgeton MSA.<ref>[https://www.census.gov/population/www/cen2000/briefs/phc-t29/tables/tab07.pdf "Census 2000 PHC-T-29. Ranking Tables for Population of Metropolitan Statistical Areas, Micropolitan Statistical Areas, Combined Statistical Areas, New England City and Town Areas, and Combined New England City and Town Areas: 1990 and 2000" Table 7], released December 30, 2003. Accessed April 22, 2019.</ref>

In 2000, [[Kent County, Delaware]] was designated the Dover MSA, and Kent County and [[Atlantic City, New Jersey|Atlantic City]] were added to the Philadelphia CSA in 2010. As a result of new 2010 definitions, based on a threshold of 15% labor interchange between MSAs, two additional MSAs were added, [[Ocean City, New Jersey]] and [[Reading, Pennsylvania]]. The CSA to which they belong is known as Philadelphia-Reading-Camden.<ref>Office of Management and Budget Bulletin 13-01, February 28, 2013, accessed on April 22, 2019, at URL https://www.bls.gov/bls/omb-bulletin-13-01-revised-delineations-of-metropolitan-statistical-areas.pdf</ref>

=== Climate Types ===
All of it is Humid Subtropical<gallery>
File:Köppen Climate Types Maryland.png|'''Maryland''' '''Köppen Climate Types'''
File:Köppen Climate Types Pennsylvania.png|'''Pennsylvania Köppen Climate Types Pennsylvania'''
File:Köppen Climate Types Delaware.png|'''Delaware''' '''Köppen Climate Types''' 
File:Köppen Climate Types New Jersey.png|'''New Jersey Köppen Climate Types'''
</gallery>