Equator in the context of Hadley Circulation

The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is bounded by the continents of Asia and Australia in the west and the Americas in the east.

At 165,250,000 square kilometers (63,800,000 square miles) in area (as defined with a southern Antarctic border), the Pacific Ocean is the largest division of the World Ocean and the hydrosphere and covers approximately 46% of Earth's water surface and about 32% of the planet's total surface area, larger than its entire land area (148,000,000 km (57,000,000 sq mi)). The centers of both the water hemisphere and the Western Hemisphere, as well as the oceanic pole of inaccessibility, are in the Pacific Ocean. Ocean circulation (caused by the Coriolis effect) subdivides it into two largely independent volumes of water that meet at the equator, the North Pacific Ocean and the South Pacific Ocean (or more loosely the South Seas). The Pacific Ocean can also be informally divided by the International Date Line into the East Pacific and the West Pacific, which allows it to be further divided into four quadrants, namely the Northeast Pacific off the coasts of North America, the Southeast Pacific off South America, the Northwest Pacific off Far Eastern/Pacific Asia, and the Southwest Pacific around Oceania.

Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surface area. With nearly 1.4 billion people as of 2021, it accounts for about 18% of the world's human population. Africa's population is the youngest among all the continents; the median age in 2012 was 19.7, when the worldwide median age was 30.4. Based on 2024 projections, Africa's population will exceed 3.8 billion people by 2100. Africa is the least wealthy inhabited continent per capita and second-least wealthy by total wealth, ahead of Oceania. Scholars have attributed this to different factors including geography, climate, corruption, colonialism, the Cold War, and neocolonialism. Despite this low concentration of wealth, recent economic expansion and a large and young population make Africa an important economic market in the broader global context, and Africa has a large quantity of natural resources.

Africa straddles the equator and the prime meridian. The continent is surrounded by the Mediterranean Sea to the north, the Arabian Plate and the Gulf of Aqaba to the northeast, the Indian Ocean to the southeast and the Atlantic Ocean to the west. France, Italy, Portugal, Spain, and Yemen have parts of their territories located on African geographical soil, mostly in the form of islands.

Singapore, officially the Republic of Singapore, is an island country and city-state in Southeast Asia. Its territory comprises one main island, 63 satellite islands and islets, and one outlying islet. The country is about one degree of latitude (137 kilometres or 85 miles) north of the equator, off the southern tip of the Malay Peninsula, bordering the Strait of Malacca to the west, the Singapore Strait to the south along with the Riau Islands in Indonesia, the South China Sea to the east and the Straits of Johor along with the State of Johor in Malaysia to the north.

In its early history, Singapore was a maritime emporium known as Temasek; subsequently, it was a major constituent of several successive thalassocratic empires. Its contemporary era began in 1819, when Stamford Raffles established Singapore as an entrepôt trading post of the British Empire. In 1867, Singapore came under direct British control as part of the Straits Settlements. During World War II, Singapore was occupied by Japan in 1942 and returned to Britain as a Crown colony following Japan's surrender in 1945. Singapore gained self-governance in 1959 and in 1963 became part of the new federation of Malaysia, alongside Malaya, North Borneo and Sarawak. Ideological differences led to Singapore's expulsion from the federation two years later; it became an independent sovereign country in 1965. After early years of turbulence and despite lacking natural resources and a hinterland, the nation rapidly developed to become one of the Four Asian Tigers.

The Northern Hemisphere is the half of Earth that is north of the equator. For other planets in the Solar System, north is defined as being in the same celestial hemisphere relative to the invariable plane of the Solar System as Earth's North Pole.

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 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.

The night sky is the nighttime appearance of celestial objects like stars, planets, and the Moon, which are visible in a clear sky between sunset and sunrise, when the Sun is below the horizon.

Natural light sources in a night sky include moonlight, starlight, and airglow, depending on location and timing. Aurorae light up the skies above the polar circles. Occasionally, a large coronal mass ejection from the Sun or simply high levels of solar wind may extend the phenomenon toward the Equator.

Biodiversity is the variability of life on Earth. It can be measured on various levels, for example, genetic variability, species diversity, ecosystem diversity and phylogenetic diversity. Diversity is not distributed evenly on Earth—it is greater in the tropics as a result of the warm climate and high primary productivity in the region near the equator. Tropical forest ecosystems cover less than one-fifth of Earth's terrestrial area and contain about 50% of the world's species. There are latitudinal gradients in species diversity for both marine and terrestrial taxa.

Since life began on Earth, six major mass extinctions and several minor events have led to large and sudden drops in biodiversity. The Phanerozoic aeon (the last 540 million years) marked a rapid growth in biodiversity via the Cambrian explosion. In this period, the majority of multicellular phyla first appeared. The next 400 million years included repeated, massive biodiversity losses. Those events have been classified as mass extinction events. In the Carboniferous, rainforest collapse may have led to a great loss of plant and animal life. The Permian–Triassic extinction event, 251 million years ago, was the worst; vertebrate recovery took 30 million years.

The Manila galleon (Spanish: Galeón de Manila; Tagalog: Galeon ng Maynila) are the Spanish trading ships that linked the Philippines in the Spanish East Indies to Mexico (New Spain), across the Pacific Ocean. The ships made one or two round-trip voyages per year between the ports of Manila and Acapulco from the late 16th to early 19th century. The term "Manila galleon" can also mean the trade route itself between Manila and Acapulco that was operational from 1565 to 1815.

The Manila galleon trade route was inaugurated in 1565 after the Augustinian friar and navigator Andrés de Urdaneta pioneered the tornaviaje or return route from the Philippines to Mexico. Urdaneta and Alonso de Arellano made the first successful round trips that year, by taking advantage of the Kuroshio Current. The galleons set sail from Cavite, in Manila Bay, at the end of June or the first week of July, sailing through the northern Pacific and reaching Acapulco in March to April of the next calendar year. The return route from Acapulco passes through lower latitudes closer to the equator, stopping over in the Marianas, then sailing onwards through the San Bernardino Strait off Cape Espiritu Santo in Samar and then to Manila Bay and anchoring again off Cavite by June or July. The trade using "Urdaneta's route" lasted until 1815, when the Mexican War of Independence broke out. The majority of these galleons were built and loaded in shipyards in Cavite, utilizing native hardwoods like the Philippine teak, with sails produced in Ilocos, and with the rigging and cordage made from salt-resistant Manila hemp. The vast majority of the galleon's crew consisted of Filipino natives; many of whom were farmers, street children, or vagrants press-ganged into service as sailors. The officers and other skilled crew were usually Spaniards (a high percentage of whom were of Basque descent). The galleons were state vessels and thus the cost of their construction and upkeep was borne by the Spanish Crown.

Tropical rainforests are dense and warm rainforests with high rainfall typically found between 10° north and south of the Equator. They are a subset of the tropical forest biome that occurs roughly within the 28° latitudes (in the torrid zone between the Tropic of Cancer and Tropic of Capricorn). Tropical rainforests are a type of tropical moist broadleaf forest, that includes the more extensive seasonal tropical forests. True rainforests usually occur in tropical rainforest climates where no dry season occurs; all months have an average precipitation of at least 60 mm (2.4 in). Seasonal tropical forests with tropical monsoon or savanna climates are sometimes included in the broader definition.

Tropical rainforests ecosystems are distinguished by their consistent, high temperatures, exceeding 18 °C (64 °F) monthly, and substantial annual rainfall. The abundant rainfall results in nutrient-poor, leached soils, which profoundly affect the flora and fauna adapted to these conditions. These rainforests are renowned for their significant biodiversity. They are home to 40–75% of all species globally, including half of the world's animal and plant species, and two-thirds of all flowering plant species. Their dense insect population and variety of trees and higher plants are notable. Described as the "world's largest pharmacy", over a quarter of natural medicines have been discovered in them. However, tropical rainforests are threatened by human activities, such as logging and agricultural expansion, leading to habitat fragmentation and loss.

The Neoproterozoic is the last of the three geologic eras of the Proterozoic eon, spanning from 1 billion to 538.8 million years ago, and is the last era of the Precambrian "supereon". It is preceded by the Mesoproterozoic era and succeeded by the Paleozoic era of the Phanerozoic eon, and is further subdivided into three periods, the Tonian, Cryogenian and Ediacaran.

One of the most severe glaciation events known in the geologic record occurred during the Cryogenian period of the Neoproterozoic, when global ice sheets may have reached the equator and created a "Snowball Earth" lasting about 100 million years. The earliest fossils of complex life are found in the Tonian period in the form of Otavia, a primitive sponge, and the earliest fossil evidence of metazoan radiation are found in the Ediacaran period, which included the namesaked Ediacaran biota as well as the oldest definitive cnidarians and bilaterians in the fossil record.

Southeast Asia is the geographical southeastern region of Asia, consisting of the regions that are situated south of China, east of the Indian subcontinent, and northwest of mainland Australia, which is part of Oceania. Southeast Asia is bordered to the north by East Asia, to the west by South Asia and the Bay of Bengal, to the east by Oceania and the Pacific Ocean, and to the south by Australia and the Indian Ocean. Apart from the British Indian Ocean Territory and two out of 26 atolls of the Maldives in South Asia, Maritime Southeast Asia is the only other subregion of Asia that lies partly within the Southern Hemisphere. Mainland Southeast Asia is entirely in the Northern Hemisphere. Timor-Leste and the southern portion of Indonesia are the parts of Southeast Asia that lie south of the equator.

The region lies near the intersection of geological plates, with both heavy seismic and volcanic activities. The Sunda plate is the main plate of the region, featuring almost all Southeast Asian countries except Myanmar, northern Thailand, northern Laos, northern Vietnam, and northern Luzon of the Philippines, while the Sunda plate only includes western Indonesia to as far east as the Indonesian province of Bali. The mountain ranges in Myanmar, Thailand, Peninsular Malaysia, and the Indonesian islands of Sumatra, Java, Bali, Lesser Sunda Islands, and Timor are part of the Alpide belt, while the islands of the Philippines and Indonesia as well as Timor-Leste are part of the Pacific Ring of Fire. Both seismic belts meet in Indonesia, causing the region to have relatively high occurrences of earthquakes and volcanic eruptions, particularly in the Philippines and Indonesia.

Today the term South Seas, or South Sea, most commonly refers to the portion of the Pacific Ocean south of the equator. The term South Sea may also be used synonymously for Oceania, or even more narrowly for Polynesia or the Polynesian Triangle, an area bounded by the Hawaiian Islands, New Zealand and Easter Island. Pacific Islanders are commonly referred to as South Sea Islanders, particularly in Australia.

The term was coined as Mar de Sur, or "South Sea",  by Spanish conquistador Vasco Núñez de Balboa in 1513 as he it encountered on the southern coast of the Isthmus of Panama and it was applied to the entirety today's Pacific Ocean. In 1520, Ferdinand Magellan named the same ocean the Pacific Ocean, and over time Magellan's name became more well-known.

Equatorial Guinea, officially the Republic of Equatorial Guinea, is a country on the west coast of Central Africa. It has an area of 28,000 square kilometres (11,000 sq mi). Formerly the colony of Spanish Guinea, its post-independence name refers to its location both near the Equator and in the African region of Guinea. As of 2024, the country had a population of 1,795,834, over 85% of whom are members of the Fang people, the country's dominant ethnic group. The Bubi people, indigenous to Bioko, are the second largest group at approximately 6.5% of the population.

Equatorial Guinea consists of two parts. The mainland region, Río Muni, is bordered by Cameroon to the north and Gabon to the south and east. It has the majority of the population and is the location of Bata, Equatorial Guinea's largest city, and Ciudad de la Paz, the country's planned future capital. Río Muni's small offshore islands include Corisco, Elobey Grande, and Elobey Chico. The insular region consists of the islands of Bioko (formerly Fernando Po) in the Gulf of Guinea and Annobón. Bioko Island is the northernmost part of Equatorial Guinea and is the site of the country's capital, Malabo. The Portuguese-speaking island nation of São Tomé and Príncipe is located between Bioko and Annobón.

A prime meridian is an arbitrarily chosen meridian (a line of longitude) in a geographic coordinate system at which longitude is defined to be 0°. On a spheroid, a prime meridian and its anti-meridian (the 180th meridian in a 360°-system) form a great ellipse. This divides the body (e.g. Earth) into two hemispheres: the Eastern Hemisphere and the Western Hemisphere (for an east-west notational system). For Earth's prime meridian, various conventions have been used or advocated in different regions throughout history. Earth's current international standard prime meridian is the IERS Reference Meridian. It is derived, but differs slightly, from the Greenwich Meridian, the previous standard.

Longitudes for the Earth and Moon are measured from their prime meridian (at 0°) to 180° east and west. For all other Solar System bodies, longitude is measured from 0° (their prime meridian) to 360°. West longitudes are used if the rotation of the body is prograde (or 'direct', like Earth), meaning that its direction of rotation is the same as that of its orbit. East longitudes are used if the rotation is retrograde.

A mangrove is a shrub or tree that grows mainly in coastal saline or brackish water. Mangroves grow in an equatorial climate, typically along coastlines and tidal rivers. They have particular adaptations to take in extra oxygen and remove salt, allowing them to tolerate conditions that kill most plants. The term is also used for tropical coastal vegetation consisting of such species. Mangroves are taxonomically diverse due to convergent evolution in several plant families. They occur worldwide in the tropics and subtropics and even some temperate coastal areas, mainly between latitudes 30° N and 30° S, with the greatest mangrove area within 5° of the equator. Mangrove plant families first appeared during the Late Cretaceous to Paleocene epochs and became widely distributed in part due to the movement of tectonic plates. The oldest known fossils of mangrove palm date to 75 million years ago.

Mangroves are salt-tolerant (halophytic) and are adapted to live in harsh coastal conditions. They contain a complex salt filtration system and a complex root system to cope with saltwater immersion and wave action. They are adapted to the low-oxygen conditions of waterlogged mud, but are most likely to thrive in the upper half of the intertidal zone.

The tropics are the region of Earth surrounding the equator, where the sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. Because of Earth's axial tilt, the width of the tropics (in latitude) is twice the tilt. The tropics are also referred to as the tropical zone and the torrid zone (see geographical zone).

Due to the sun's high angle throughout the year, the tropics receive the most solar energy over the course of the year, and consequently have the highest temperatures on the planet. Even when not directly overhead, the sun is still close to overhead throughout the year, therefore the tropics also have the lowest seasonal variation on the planet; "winter" and "summer" lose their temperature contrast. Instead, seasons are more commonly divided by precipitation variations than by temperature variations or daylight hours.

A nautical mile is a unit of length used in air, marine, and space navigation, and for the definition of territorial waters. Historically, it was defined as the meridian arc length corresponding to one minute (⁠1/60⁠ of a degree) of latitude at the equator, so that Earth's polar circumference is very near to 21,600 nautical miles (that is 60 minutes × 360 degrees). Today the international nautical mile is defined as exactly 1,852 metres (about 6,076 ft; 1.151 mi). The derived unit of speed is the knot, one nautical mile per hour.

The nautical mile is not part of the International System of Units (SI), nor is it accepted for use with SI. However, it is still in common use globally in air, marine, and space contexts due to its correspondence with geographic coordinates.