The <Location> field specifies the name of a place on Earth, a location within the Earth, a vertical location, or a location outside of Earth. The <Location> keywords are a 5-level hierarchy of controlled keywords under the following Categories:

• Continent: specifies continents:
• Africa
• Antarctica
• Asia
• Australia/New Zealand
• Europe
• North America
• South America
• Ocean: specifies an ocean body:
• Arctic Ocean
• Atlantic Ocean
• Indian Ocean   
• Pacific Ocean
• Southern Ocean
• Geographic Region: specifies a region on Earth (e.g., Polar)
  • Arctic
  • Eastern Hemisphere
  • Equatorial
  • Eurasia
  • Global
  • Global Land
  • Global Ocean
  • Mid-latitude
  • Northern Hemisphere
  • Oceania
  • Polar
  • Sahel
  • Southern Hemisphere
  • Tropics
  • Western Hemisphere
• Solid Earth: specifies a region within the Earth:
• Core
• Crust
• Mantle
• Space: specifies a region outside of Earth, particularly regions of Earth-Sun interactions:
• Earth Magnetic Field
• Solar Region
• Vertical Location: specifies a region in the vertical direction, either in the atmosphere or under the oceans:
• Boundary Layer
• Ionosphere
• Land Surface
• Mesosphere
• Sea Floor
• Sea Surface
• Stratosphere
• Thermosphere
• Troposphere

<Location>
   <Location_Category>Location Category keyword
   </Location_Category>
   <Location_Type>Location type keyword</Location_Type>
   <Location_Subregion1>Location Subregion1 keyword</Location_Subregion1>
   <Location_Subregion2>Location Subregion2 keyword</Location_Subregion2>
   <Location_Subregion3>Location Subregion3 keyword</Location_Subregion3>
   <Detailed_Location>Text</Detailed_Location>
</Location>

• <Detailed_Location> can contain up to 80 characters.
• Characters may be selected from the UTF-8 character set.

• The <Location> field is highly recommended and repeatable.
• The <Location> subfields are not repeatable within the <Location> field.
• Location keywords must be selected from the set of controlled Location keywords.
• <Detailed_Location> allows authors to include any location keywords that are not available in the controlled keyword list.

<Location>
    <Location_Category>CONTINENT</Location_Category>
    <Location_Type>NORTH AMERICA</Location_Type>
    <Location_Subregion1>UNITED STATES OF AMERICA</Location_Subregion1>
    <Location_Subregion2>MARYLAND</Location_Subregion2>
    <Location_Subregion3>BALTIMORE</Location_Subregion3>
    <Detailed_Location>Middle River</Detailed_Location>
</Location>