Introduction
Officially the City of Los Angeles and often abbreviated as L.A., is the largest city in California. With an estimated population of nearly four million people, it is the second most populous city in the United States (after New York City) and the third most populous city in North America (after Mexico City and New York City). Los Angeles is known for its Mediterranean climate, ethnic diversity, Hollywood entertainment industry, and its sprawling metropolis.
Los Angeles lies in a basin in Southern California, adjacent to the Pacific Ocean, with mountains as high as 10,000 feet (3,000 m), and deserts. The city, which covers about 469 square miles (1,210 km2), is the seat of Los Angeles County, the most populous county in the United States. The Los Angeles metropolitan area (MSA) is home to 13.1 million people, making it the second-largest metropolitan area in the nation after New York. Greater Los Angeles includes metro Los Angeles as well as the Inland Empire and Ventura County. It is the second most populous U.S. combined statistical area, also after New York, with a 2015 estimate of 18.7 million people.
History and Economy
Pre-Colonial History and Economy
Home to the Chumash and Tongva, the area that became Los Angeles was claimed by Juan Rodríguez Cabrillo for Spain in 1542. The city was founded on September 4, 1781, under Spanish governor Felipe de Neve, on the village of Yaanga.
The Los Angeles coastal area was settled by the Tongva (Gabrieleños) and Chumash tribes. Los Angeles would eventually be founded on the village of iyáangẚ or Yaanga (written "Yang-na" by the Spanish), meaning "poison oak place." Maritime explorer Juan Rodríguez Cabrillo claimed the area of southern California for the Spanish Empire in 1542 while on an official military exploring expedition moving north along the Pacific coast from earlier colonizing bases of New Spain in Central and South America. Gaspar de Portolà and Franciscan missionary Juan Crespí, reached the present site of Los Angeles on August 2, 1769.
It became a part of Mexico in 1821 following the Mexican War of Independence. In 1848, at the end of the Mexican–American War, Los Angeles and the rest of California were purchased as part of the Treaty of Guadalupe Hidalgo, and thus became part of the United States. Los Angeles was incorporated as a municipality on April 4, 1850, five months before California achieved statehood.The discovery of oil in the 1890s brought rapid growth to the city. The city was further expanded with the completion of the Los Angeles Aqueduct in 1913, which delivers water from Eastern California.
Los Angeles has a diverse economy and hosts businesses in a broad range of professional and cultural fields. It also has the busiest container port in the Americas. The Los Angeles metropolitan area also has a gross metropolitan product of $1.0 trillion(as of 2017), making it the third-largest city by GDP in the world, after the Tokyo and New York City metropolitan areas. Los Angeles hosted the 1932 and 1984 Summer Olympics and will host the 2028 Summer Olympics.
Geography and Vegetation
The city of Los Angeles covers a total area of 502.7 square miles (1,302 km2), comprising 468.7 square miles (1,214 km2) of land and 34.0 square miles (88 km2) of water. The city extends for 44 miles (71 km) north-south and for 29 miles (47 km) east-west. The perimeter of the city is 342 miles (550 km). Los Angeles is both flat and hilly. The highest point in the city proper is Mount Lukens at 5,074 ft (1,547 m), located at the northeastern end of the San Fernando Valley. The eastern end of the Santa Monica Mountains stretches from Downtown to the Pacific Ocean and separates the Los Angeles Basin from the San Fernando Valley.
Other hilly parts of Los Angeles include the Mt. Washington area north of Downtown, eastern parts such as Boyle Heights, the Crenshaw district around the Baldwin Hills, and the San Pedro district. Surrounding the city are much higher mountains. Immediately to the north lie the San Gabriel Mountains, which is a popular recreation area for Angelenos. Its high point is Mount San Antonio, locally known as Mount Baldy, which reaches 10,064 feet (3,068 m). Further afield, the highest point in the Greater Los Angeles area is San Gorgonio Mountain, with a height of 11,503 feet (3,506 m).
The Los Angeles River, which is largely seasonal, is the primary drainage channel. It was straightened and lined in 51 miles (82 km) of concrete by the Army Corps of Engineers to act as a flood control channel. The river begins in the Canoga Park district of the city, flows east from the San Fernando Valley along the north edge of the Santa Monica Mountains, and turns south through the city center, flowing to its mouth in the Port of Long Beach at the Pacific Ocean. The smaller Ballona Creek flows into the Santa Monica Bay at Playa del Rey.
Los Angeles has a Mediterranean climate (Köppen Csb on the coast and most of downtown, Csb near the metropolitan region to the west), and receives just enough annual precipitation to avoid semi-arid climate (BSh),. Daytime temperatures are generally temperate all year round. In winter, they average around 68 °F (20 °C) giving it a tropical feel although it is a few degrees too cool to be a true tropical climate on average due to cool night temperatures. Los Angeles has plenty of sunshine throughout the year, with an average of only 35 days with measurable precipitation annually.
Los Angeles is rich in native plant species partly because of its diversity of habitats, including beaches, wetlands, and mountains. The most prevalent plant communities are coastal sage scrub, chaparral shrubland, and riparian woodland. Native plants include: the California poppy, matilija poppy, toyon, Ceanothus, Chamise, Coast Live Oak, sycamore, willow and Giant Wildrye. Many of these native species, such as the Los Angeles sunflower, have become so rare as to be considered endangered. Although it is not native to the area, the official tree of Los Angeles is the Coral Tree (Erythrina caffra) and the official flower of Los Angeles is the Bird of Paradise (Strelitzia reginae).[69] Mexican Fan Palms, Canary Island Palms, Queen Palms, Date Palms, and California Fan Palms are common in the Los Angeles area, although only the last is native.
Los Angeles Climate
Temperatures in the coastal basin exceed 90 °F (32 °C) on a dozen or so days in the year, from one day a month in April, May, June and November to three days a month in July, August, October and to five days in September. Temperatures in the San Fernando and San Gabriel Valleys are considerably warmer. Temperatures are subject to substantial daily swings; in inland areas the difference between the average daily low and the average daily high is over 30 °F (17 °C). The average annual temperature of the sea is 63 °F (17 °C), from 58 °F (14 °C) in January to 68 °F (20 °C) in August. Hours of sunshine total more than 3,000 per year, from an average of 7 hours of sunshine per day in December to an average of 12 in July.
The Los Angeles area is also subject to phenomena typical of a microclimate, causing extreme variations in temperature in close physical proximity to each other. For example, the average July maximum temperature at the Santa Monica Pier is 70 °F (21 °C) whereas it is 95 °F (35 °C) in Canoga Park, 15 miles (24 km) away. The city, like much of the southern California coast, is subject to a late spring/early summer weather phenomenon called "June Gloom". This involves overcast or foggy skies in the morning that yield to sun by early afternoon.
Downtown Los Angeles averages 14.93 in (379 mm) of precipitation annually, mainly occurring between November and March, generally in the form of moderate rain showers, but sometimes as heavy rainfall during winter storms. Rainfall is usually higher in the hills and coastal slopes of the mountains because of orographic uplift. Summer days are usually rainless. Rarely, an incursion of moist air from the south or east can bring brief thunderstorms in late summer, especially to the mountains. The coast gets slightly less rainfall, while the inland and mountain areas get considerably more. Years of average rainfall are rare. The usual pattern is year to year variability, with a short string of dry years of 5–10 in (130–250 mm) rainfall, followed by one or two wet years with more than 20 in (510 mm). Wet years are usually associated with warm water El Niño conditions in the Pacific, dry years with cooler water La Niña episodes. A series of rainy days can bring floods to the lowlands and mudslides to the hills, especially after wildfires have denuded the slopes.
Both freezing temperatures and snowfall are extremely rare in the city basin and along the coast, with the last occurrence of a 32 °F (0 °C) reading at the downtown station being January 29, 1979; freezing temperatures occur nearly every year in valley locations while the mountains within city limits typically receive snowfall every winter. The greatest snowfall recorded in downtown Los Angeles was 2.0 inches (5 cm) on January 15, 1932. While the most recent snowfall occurred in February 2019, the first snowfall since 1962, with snow falling in areas adjacent to Los Angeles as recently as January 2021. At the official downtown station, the highest recorded temperature is 113 °F (45 °C) on September 27, 2010, while the lowest is 28 °F (−2 °C), on January 4, 1949. Within the City of Los Angeles, the highest temperature ever officially recorded is 121 °F (49 °C), on September 6, 2020, at the weather station at Pierce College in the San Fernando Valley neighborhood of Woodland Hills. During autumn and winter, Santa Ana winds sometimes bring much warmer and drier conditions to Los Angeles, and raise wildfire risk.
Enivornmental Issues
Los Angeles suffers from air pollution in the form of smog. The Los Angeles Basin and the San Fernando Valley are susceptible to atmospheric inversion, which holds in the exhausts from road vehicles, airplanes, locomotives, shipping, manufacturing, and other sources. The percentage of small particle pollution (the kind that penetrates into the lungs) coming from vehicles in the city can get as high as 55 percent. The smog season lasts from approximately May to October.While other large cities rely on rain to clear smog, Los Angeles gets only 15 inches (380 mm) of rain each year: pollution accumulates over many consecutive days. Issues of air quality in Los Angeles and other major cities led to the passage of early national environmental legislation, including the Clean Air Act. When the act was passed, California was unable to create a State Implementation Plan that would enable it to meet the new air quality standards, largely because of the level of pollution in Los Angeles generated by older vehicles. More recently, the state of California has led the nation in working to limit pollution by mandating low-emission vehicles. Smog is expected to continue to drop in the coming years because of aggressive steps to reduce it, which include electric and hybrid cars, improvements in mass transit, and other measures.
