# Longhurst code

Longhurst code refers to a set of geospatial four-letter geocodes for referencing geographic regions in oceanography.
The set of 56 geocodes represent biogeochemical provinces that partition the pelagic environment. It is assumed that each province represents a unique set of environmental conditions.
They are named after Alan R. Longhurst, the author of "Ecological Geography of the Sea", the textbook in which these codes are defined.
These codes have also been used in bioinformatic databases such as IMG to represent sample origins for sequenced microbial genomes, as a supplement to latitude and longitude coordinate metrics.
| longhurst_code | province_name | ocean | biome |
| FKLD | Southwest Atlantic shelves | Atlantic | Coastal |
| BRAZ | Brazilian current coast | Atlantic | Coastal |
| BENG | Benguela current coast | Atlantic | Coastal |
| GUIN | Guinea current coast | Atlantic | Coastal |
| CNRY | Canary current coast | Atlantic | Coastal |
| GUIA | Guianas coast | Atlantic | Coastal |
| NECS | Northeast Atlantic shelves | Atlantic | Coastal |
| NWCS | Northwest Atlantic shelves | Atlantic | Coastal |
| ARCT | Atlantic Arctic | Atlantic | Polar |
| SARC | Atlantic sub-Arctic | Atlantic | Polar |
| SATL | South Atlantic gyral | Atlantic | Trade wind |
| ETRA | Eastern tropical Atlantic | Atlantic | Trade wind |
| WTRA | Western tropical Atlantic | Atlantic | Trade wind |
| CARB | Caribbean | Atlantic | Trade wind |
| NATR | North Atlantic tropical gyral | Atlantic | Trade wind |
| NAST E | Northeast Atlantic subtropical gyral | Atlantic | Westerly |
| MEDI | Mediterranean Sea | Atlantic | Westerly |
| NAST W | Northwest Atlantic subtropical gyral | Atlantic | Westerly |
| GFST | Gulf Stream | Atlantic | Westerly |
| NADR | North Atlantic Drift | Atlantic | Westerly |
| HUMB | Humboldt current coast | Pacific | Coastal |
| AUSE | East Australian coast | Pacific | Coastal |
| SUND | Sunda-Arafura shelves | Pacific | Coastal |
| CHIN | China Sea | Pacific | Coastal |
| CAMR | Central American coast | Pacific | Coastal |
| ALSK | Alaska coastal downwelling | Pacific | Coastal |
| NEWZ | New Zealand coast | Pacific | Coastal |
| CCAL | Coastal Californian current | Pacific | Coastal |
| BERS | North Pacific epicontinental sea | Pacific | Polar |
| ARCH | Archipelagic deep basins | Pacific | Trade wind |
| PEQD | Pacific equatorial divergence | Pacific | Trade wind |
| PNEC | North Pacific equatorial counter current | Pacific | Trade wind |
| NPTG | North Pacific Tropical gyre | Pacific | Trade wind |
| C(O)CAL | California current | Pacific | Trade wind |
| SPSG | South Pacific gyre | Pacific | Trade wind |
| WARM | Western Pacific warm pool | Pacific | Trade wind |
| TASM | Tasman Sea | Pacific | Westerly |
| KURO | Kuroshio current | Pacific | Westerly |
| PSAE | Eastern Pacific subarctic gyres | Pacific | Westerly |
| PSAW | Western Pacific subarctic gyres | Pacific | Westerly |
| NPPF | North Pacific polar front | Pacific | Westerly |
| NPSW | Northwest Pacific subtropical | Pacific | Westerly |
| NPSE | Northeast Pacific subtropical | Pacific | Westerly |
| EAFR | East African coast | Indian | Coastal |
| AUSW | Western Australian and Indonesian coast | Indian | Coastal |
| IND E | Eastern India coast | Indian | Coastal |
| REDS | Red Sea, Persian Gulf | Indian | Coastal |
| IND W | Western India coast | Indian | Coastal |
| ISSG | Indian South subtropical gyre | Indian | Trade wind |
| MONS | Indian monsoon gyre | Indian | Trade wind |
| ARAB | Northwest Arabian Sea upwelling | Indian | Westerly |
| SSTC | South subtropical convergence | Antarctic | Westerly |
| SANT | Subantarctic water ring | Antarctic | Westerly |
| ANTA | Antarctic | Antarctic | Polar |
| APLR | Austral polar | Antarctic | Polar |
| BPRL | Boreal polar | Arctic | Polar |