Instruct: Given a question, retrieve relevant passages that answer the question.
Query: How does El Nino affect North American weather patterns?
There are many global patterns that affect and contribute to the climate of the Eastern Temperate Forest region, such as global ocean currents, El Nino, La Nina, the Gulf Stream current, and global air circulation patterns. El Niño, caused by warmer sea-surface temperatures in the Pacific Ocean, can lead to "wet winters" and warm episodes occurring between the months of December and February in the southeastern region of the United States Eastern Temperate Forest. La Niña is caused by cooler than normal sea-surface temperatures in the central and eastern tropical Pacific Ocean, it leads to drier than normal conditions in the winter months in the Southeast region of the Eastern Temperate Forest. The global ocean current that effects the Eastern Temperate Forest most is the Gulf Stream current which brings a warm flow of water from South to North along the eastern coast of North America in the Atlantic Ocean, it keeps temperatures in this region relatively warm. The winds that have the greatest effect on the climate of the region are the prevailing westerlies and the tropical easterlies. The prevailing westerlies, caused by the Coriolis Effect, explain why most major events that occur in North America come from the west and proceed east, which is where the majority of the Eastern Temperate Forest is located.
The roots of the TOGA program can be traced back to the 1920s and the work of Sir Gilbert Walker on what became known as the Southern Oscillation, an apparent linkage between atmospheric pressure anomalies throughout the Pacific Ocean that appeared to be a major driver of weather patterns. This work was furthered by Jacob Bjerknes in the 1960s when he solidified the link between the El Nino phenomena, a winter warm anomaly in the normally cool water off the coast of Peru, with the southern oscillation. The combined El Nino – Southern Oscillation, or ENSO, turned out to be a major contributor to seasonal climate variability with both human and economic implications. Study of these linked phenomena continued through the 1970s and 1980s via a variety observational and modeling studies which included the discovery of equatorial kelvin waves, a potential precursor to the ENSO phenomena.
This large variability is caused by discrete eddies, near-inertial motions, and internal tides. Climate patterns such as the North Pacific Gyre Oscillation (NPGO), El Nino/Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) affect the interannual variability in primary productivity in the NPSG. DiLorenzo et al., 2008 These conditions can have profound effects on biological processes within this habitat, they have the ability to shift sea surface temperature (SST), chlorophyll patterns, nutrient patterns, oxygen concentrations, mixed layer depths, and thus the carrying capacity (amount of life this habitat can carry) of the NPSG.
Throughout the year, the South Pacific High influences the climate by bringing cold, moist air masses originating from Patagonia. During the most intense cold waves, they form when a transient high pressure system located in the South Pacific Ocean moves eastwards to the southern tip of South America. As it begins to move, this high pressure system strengthens the South Pacific High and is forced to move southwards to south of 40S where the Andes are shorter in height. As well, an upper level ridge forms over the South Pacific Ocean along with an upper level trough extending from subtropical latitudes to the South Atlantic Ocean. At the same time, a low pressure system forms over the South Atlantic Ocean which eventually strengthens. The formation a cold front associated with it moves to the northeast owing to the topographic barrier that the Andes forms. The passage of the cold front to the northeast leads to the movement of the high pressure system from the South Pacific Ocean into the southern tip of South America. All of these conditions lead to strong anticyclogenesis to the east of the Andes and thus, the high pressure system intensifies as it enters southern Argentina. When both the high pressure system (over southern Argentina) and low pressure system strengthen, it creates a very strong pressure gradient that draws cold air from the south, strengthening southerly winds. Owing to the topographic barrier of the Andes, it forces and channels the cold air to accumulate on the eastern side of the Andes. This generates an ageostropic component from the south (due to a reduction in the Coriolis force caused by accumulation of cold air on the eastern side of the Andes) that draw this cold air northwards, which is driven by this pressure gradient. Cold air can move northwards until 18S when the blocking effect of the Andes is smaller due to a change in its orientation. Overall, these conditions results in the coldest temperatures due to the cold masses from high latitudes being pulled northwards. A weaker cold wave occurs when the South Pacific High remains over the ocean and does not have a migratory high pressure system originating from the South Pacific High that moves east of the Andes (it builds over the Andes). Although this occurs throughout the year, during winters, it leads to cold temperatures while during summer, it leads to strong and deep convections. These convections are responsible for about 50% of summer precipitation south of 25S.
The United States has the most tornadoes of any country, nearly four times more than estimated in all of Europe, excluding waterspouts. This is mostly due to the unique geography of the continent. North America is a large continent that extends from the tropics north into arctic areas, and has no major east-west mountain range to block air flow between these two areas. In the middle latitudes, where most tornadoes of the world occur, the Rocky Mountains block moisture and buckle the atmospheric flow, forcing drier air at mid-levels of the troposphere due to downsloped winds, and causing the formation of a low pressure area downwind to the east of the mountains. Increased westerly flow off the Rockies force the formation of a dry line when the flow aloft is strong, while the Gulf of Mexico fuels abundant low-level moisture in the southerly flow to its east. This unique topography allows for frequent collisions of warm and cold air, the conditions that breed strong, long-lived storms throughout the year. A large portion of these tornadoes form in an area of the central United States known as Tornado Alley. This area extends into Canada, particularly Ontario and the Prairie Provinces, although southeast Quebec, the interior of British Columbia, and western New Brunswick are also tornado-prone. Tornadoes also occur across northeastern Mexico.
The North Pole is substantially warmer than the South Pole because it lies at sea level in the middle of an ocean (which acts as a reservoir of heat), rather than at altitude on a continental land mass. Despite being an ice cap, it shares some characteristics with a tundra climate ("ETf") due to the July and August temperatures peaking just above freezing.
Northwest Argentina is predominantly dry, hot, and subtropical. Owing to its rugged topography, the region is climatically diverse, depending on the altitude, temperature, and distribution of precipitation. Consequently, vegetation differs within these different climate types. In general, the climate can be divided into two main types: a cold arid or semi-arid climate at the higher altitudes, and warmer subtropical climate in the eastern parts of the region. Under the Köppen climate classification, the region has 5 different climate types: semi–arid ("BS"), arid ("BW"), temperate climate without a dry season and with a dry season ("Cf" and "Cw" respectively), and an alpine climate at the highest altitudes.
Northwest Argentina is predominantly dry and hot and classified as subtropical. Owing to its rugged topography, the region is climatically diverse, depending on the altitude, temperature and distribution of precipitation. Consequentially, the vegetation will differ at these different climate types. In general, the climate can be divided into 2 main types: a cold arid or semi-arid climate at the higher altitudes and warmer subtropical climate in the eastern parts of the region. Under the Köppen climate classification, the region has 5 different climate types which are semi–arid ("BS"), arid ("BW"), without a dry season and with a dry season ("Cf" and "CW" respectively) and an alpine climate at the highest altitudes.
The American River headwaters lie along about along the Sierra Crest from Mount Lincoln in the north () where it adjoins the watersheds of the South Yuba and Truckee Rivers, to Winnemucca Lake in the Mokelumne Wilderness, where it meets the watersheds of the Mokelumne and Carson Rivers. Lands east of the American River watershed divide drain into Lake Tahoe, which flows into the Truckee River. During most years, a significant snowpack builds up in the Sierra Nevada which provides water during the hot, dry summers. In warmer winters much of the precipitation may fall as rain instead, causing flooding, but resulting in lower summer flows due to the lack of snow. Due to California's highly variable weather patterns, runoff volumes in the American River can rise and fall drastically from one year to the next.
Average annual precipitation decreases east to west from about in the southeast corner of the state to about in the Panhandle. Humidity also decreases significantly from east to west. Snowfall across the state is fairly even, with most of Nebraska receiving between of snow each year. Nebraska's highest-recorded temperature was in Minden on July 24, 1936. The state's lowest-recorded temperature was in Camp Clarke on February 12, 1899.
The annual average rainfall maxima across the continent lie across the northwest from northwest Brazil into northern Peru, Colombia, and Ecuador, then along the Atlantic coast of the Guyanas and far northern Brazil, as well as within the southern half of Chile. Lloró, a town situated in Chocó, Colombia, is probably the place with the largest measured rainfall in the world, averaging 13,300 mm per year (523.6 in). In fact, the whole Department of Chocó is extraordinarily humid. Tutunendo, a small town situated in the same department, is one of the wettest places on earth, averaging 11,394 mm per year (448 in); in 1974 the town received 26,303 mm (86 ft 3½ in), the largest annual rainfall measured in Colombia. Unlike Cherrapunji, which receives most of its rainfall between April and September, Tutunendo receives rain almost uniformly distributed throughout the year. The months of January and February have somewhat less frequent storms. On average, Tutunendo has 280 days with rainfall per year. Over ⅔ of the rain (68%) falls during the night. The average relative humidity is 90% and the average temperature is 26.4 °C. Quibdó, the capital of Chocó, receives the most rain in the world among cities with over 100,000 inhabitants: per year. Storms in Chocó can drop 500 mm (19.7 in) of rainfall in a day. This amount is more than falls in many cities in a year's time. The Andes mountain range blocks Pacific moisture that arrives in that continent, resulting in a desertlike climate just downwind across western Argentina.
The same monsoon trough that spawned Connie also produced an area of convection southeast of Diego Garcia on January 28. The circulation slowly organized, and the MFR classified it as a tropical disturbance on January 30. A nearby trough steered the system southeastward initially and later to the southwest. On January 31, the system became a tropical depression, and later Moderate Tropical Storm Damienne the next day, reaching peak winds of 65 km/h (40 mph). Also on February 1, the JTWC initiated warnings on Tropical Cyclone 10S, which estimated 1‑minute winds of 95 km/h (60 mph). Increased wind shear removed the convection on February 2, causing marked weakening, and prompting the JTWC to discontinue advisories that day. This was despite forecasts of strengthening to near tropical cyclone status. As a weak tropical disturbance, Damienne turned to a rapid westward motion, passing north of Rodrigues and Tromelin. The circulation dissipated on February 7 off the northeast coast of Madagascar.
On February 1, a low-pressure area formed within the monsoon trough to the south of Indonesia, which would eventually become Tropical Cyclone Leon in the Australian basin, as well as Tropical Cyclone 11S according to JTWC. The storm tracked westward across much of the Indian Ocean, fluctuating in strength due to changes in the atmosphere. After crossing 90° E, the MFR began tracking the system as Tropical Storm Eline on February 8. The storm continued westward across the Indian Ocean and intensified greatly as it approached the east coast of Madagascar. Late on February 17, Eline made landfall near Mahanoro with 10‑minute winds of 165 km/h (105 mph), making it the strongest storm to hit the country in several decades. The storm rapidly weakened over land, but restrengthened in the Mozambique Channel to reach peak 10‑minute winds of 185 km/h (115 mph). On February 22, Eline made landfall about 80 km (50 mi) south of Beira, Mozambique near peak intensity and quickly weakened over land. The well-defined circulation moved across southern African, finally dissipating over eastern Namibia on February 29. Throughout its duration, Leon–Eline lasted 29 days, a record longevity for a storm in the south-west Indian Ocean. The track was over 11,000 km (6,800 mi), or about 25% of the Earth's circumference.
Due to its vast size and range of altitudes, Argentina possesses a wide variety of climatic regions, ranging from the hot subtropical region in the north to the cold subantarctic in the far south. Lying between those is the Pampas region, featuring a mild and humid climate. Many regions have different, often contrasting, microclimates. In general, Argentina has four main climate types: warm, moderate, arid, and cold in which the relief features, and the latitudinal extent of the country, determine the different varieties within the main climate types.
Tornadoes have been recorded on all continents except Antarctica and are most common in the middle latitudes where conditions are often favorable for convective storm development. The United States has the most tornadoes of any country, as well as the strongest and most violent tornadoes. A large portion of these tornadoes form in an area of the central United States popularly known as Tornado Alley. Other areas of the world that have frequent tornadoes include significant portions of Europe, South Africa, Philippines, Bangladesh, parts of Argentina, Uruguay, and southern and southeast Brazil, northern Mexico, New Zealand, and far eastern Asia.
In the temperate and polar regions, seasons are marked by changes in the amount of sunlight, which in turn often causes cycles of dormancy in plants and hibernation in animals. These effects vary with latitude and with proximity to bodies of water. For example, the South Pole is in the middle of the continent of Antarctica and therefore a considerable distance from the moderating influence of the southern oceans. The North Pole is in the Arctic Ocean, and thus its temperature extremes are buffered by the water. The result is that the South Pole is consistently colder during the southern winter than the North Pole during the northern winter.
On May 19, 2011, NOAA released their first forecast for the 2011 Atlantic hurricane season. The organization expected 12–18 named storms, 6–10 hurricanes, and 3–6 major hurricanes would form in the Atlantic during 2011, citing above-normal sea surface temperatures, a weakening La Niña, and the effect of the warm regime of the Atlantic multidecadal oscillation. NOAA also stated that, when looking at climate models, "activity comparable to some of the active seasons since 1995" could occur. On May 26, the UK Met Office (UKMO) issued a forecast of a slightly above-average season. They predicted 13 tropical storms with a 70% chance that the number would fall between 10 and 17. However, they did not – and do not – issue forecasts on the number of hurricanes and major hurricanes. The team also predicted an ACE Index of 151 with a 70% chance that the index would be in the range 89 to 212.
The US National Oceanic and Atmospheric Administration (NOAA) monitors for bleaching "hot spots", areas where sea surface temperature rises 1 °C or more above the long-term monthly average. The "hot spots" are the location in which thermal stress is measured and with the development of Degree Heating Week (DHW), the coral reef's thermal stress is monitored. Global coral bleaching is being detected earlier due to the satellite remote sensing the rise of sea temperatures. It is necessary to monitor the high temperatures because coral bleaching events are affecting coral reef reproduction and normal growth capacity, as well as it weakening corals, eventually leading to their mortality. This system detected the worldwide 1998 bleaching event, that corresponded to the 1997–98 El Niño event. Currently, 190 reef sites around the globe are monitored by the NOAA, and send alerts to research scientists and reef managers via NOAA Coral Reef Watch (CRW) website. By monitoring the warming of sea temperatures, the early warnings of coral bleaching, alerts reef managers to prepare and draw awareness to future bleaching events. The first mass global bleaching events were recorded in 1998 and 2010, which was when the El Niño caused the oceans temperatures to rise and worsened the corals living conditions. The 2014–2017 El Niño was recorded to be the longest and most damaging to the corals, which harmed over 70% of our coral reefs. Over two thirds of the Great Barrier Reef have been reported to be bleached or dead.
The EAIS holds enough ice to raise global sea levels by 53.3 m and is considerably larger in area and mass than the West Antarctic Ice Sheet (WAIS). It is separated from the WAIS by the Transantarctic Mountains. The EAIS is the driest, windiest, and coldest place on Earth, with temperatures reported down to nearly -100°C. The EAIS holds the thickest ice on Earth, at 15,700 ft (4,800 m). It is home to the geographic South Pole and the Amundsen-Scott South Pole Station.
Winter temperatures at the northernmost weather station in Greenland can range from about , averaging around , with the North Pole being slightly colder. However, a freak storm caused the temperature to reach for a time at a World Meteorological Organization buoy, located at 87.45°N, on December 30, 2015. It was estimated that the temperature at the North Pole was between during the storm. Summer temperatures (June, July, and August) average around the freezing point (). The highest temperature yet recorded is , much warmer than the South Pole's record high of only . A similar spike in temperatures occurred on November 15, 2016 when temperatures hit freezing. Yet again, February 2018 featured a storm so powerful that temperatures at Cape Morris Jesup, the world's northernmost weather station in Greenland, reached and spent 24 straight hours above freezing. Meanwhile, the pole itself was estimated to reach a high temperature of . This same temperature of was also recorded at the Hollywood Burbank Airport in Los Angeles at the very same time.
The large size of Texas and its location at the intersection of multiple climate zones gives the state highly variable weather. The Panhandle of the state has colder winters than North Texas, while the Gulf Coast has mild winters. Texas has wide variations in precipitation patterns. El Paso, on the western end of the state, averages of annual rainfall, while parts of southeast Texas average as much as per year. Dallas in the North Central region averages a more moderate per year.
The Prediction and Research Moored Array in the Atlantic, also known as PIRATA, is a system of moored observation buoys in the tropical Atlantic Ocean which collect meteorological and oceanographic data. The data collected by the PIRATA array helps scientists to better understand climatic events in the Tropical Atlantic and to improve weather forecasting and climate research worldwide. Climatic and oceanic events in the tropical Atlantic, such as the Tropical Atlantic SST Dipole affect rainfall and climate in both West Africa and Northeast Brazil. The northern tropical Atlantic is also a major formation area for hurricanes affecting the West Indies and the United States. Alongside the RAMA array in the Indian Ocean and the TAO/TRITON network in the Pacific Ocean, PIRATA forms part of the worldwide system of tropical ocean observing buoys.
The direction of the wind at various levels of the atmosphere determines local climate and can result in severe weather patterns. For example, in an El Nino winter the presence of warm water in the eastern Pacific Ocean can shift the position of a subtropical jet stream. This results in heavy rainfall in the tropical wet forest ecoregion. Also, in a warming climate the Hadley cell could increase the severity of climate. As a result, the ecoregion may become hotter and wetter for longer periods of time.
ENSO (El Niño Southern Oscillation) will affect monsoon patterns more intensely in the future as climate change warms up the ocean's water. Crops that lie on the equatorial belt or under the tropical Walker circulation, such as rice, will be affected by varying monsoon patterns and more unpredictable weather. Scheduled planting and harvesting based on weather patterns will become less effective.
El Nino affects the global climate and disrupts normal weather patterns, which as a result can lead to intense storms in some places and droughts in others.
Climate in the Banten region is strongly influenced by Monsoon wind and La Nina or El Nino Wave . When the rainy season (November - March) the weather is dominated by the West wind (of Sumatra, the Indian Ocean south of India) are joined by winds from Asia passing through the South China Sea. August), the weather is dominated by the East wind which causes Banten harsh drought, especially in the northern part of the coast, especially when ongoing El Nino. Temperatures in coastal areas and hills ranging between 22 °C and 32 °C, while the temperature in the mountains with an altitude of between 400 –1350 m above sea level at between 18 °C -29 °C.
The highest rainfall of 2712–3670 mm in the rainy season months of September to May cover 50% area of Pandeglang west and rainfall 335–453 mm in the month from September to May cover 50% area of Serang Regency North, the entire area of the city of Cilegon, 50% area of Tangerang regency north and the entire area of the city of Tangerang. In the dry season, the highest rainfall of 615–833 mm in April–December cover 50% area of Serang Regency north, the whole area of the city of Cilegon, 50% area of Tangerang District north and the entire area of the city of Tangerang, while the bulk the lowest rainfall in the dry season as much as 360–486 mm in the month of June to September 50% coverage area of Tangerang Regency south and 15% area of southeastern Serang District.