Tropical cyclones in the context of "Accumulated cyclone energy"

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⭐ Core Definition: Tropical cyclones

A tropical cyclone is a rapidly rotating storm system with a low-pressure area, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls. Depending on its location and strength, a tropical cyclone is called a hurricane (/ˈhʌrɪkən, -kn/), typhoon (/tˈfn/), tropical storm, cyclonic storm, tropical depression, or simply cyclone. A hurricane is a strong tropical cyclone that occurs in the Atlantic Ocean or northeastern Pacific Ocean. A typhoon is the same thing which occurs in the northwestern Pacific Ocean. In the Indian Ocean and South Pacific, comparable storms are referred to as "tropical cyclones". In modern times, on average around 80 to 90 named tropical cyclones form each year around the world, over half of which develop hurricane-force winds of 65 kn (120 km/h; 75 mph) or more.

Tropical cyclones typically form over large bodies of relatively warm water. They derive their energy through the evaporation of water from the ocean surface, which ultimately condenses into clouds and rain when moist air rises and cools to saturation. This energy source differs from that of mid-latitude cyclonic storms, such as nor'easters and European windstorms, which are powered primarily by horizontal temperature contrasts. Tropical cyclones are typically between 100 and 2,000 km (62 and 1,243 mi) in diameter. The strong rotating winds of a tropical cyclone are a result of the conservation of angular momentum imparted by the Earth's rotation as air flows inwards toward the axis of rotation. As a result, cyclones rarely form within 5° of the equator. South Atlantic tropical cyclones are very rare due to consistently strong wind shear and a weak Intertropical Convergence Zone. In contrast, the African easterly jet and areas of atmospheric instability give rise to cyclones in the Atlantic Ocean and Caribbean Sea.

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👉 Tropical cyclones in the context of Accumulated cyclone energy

Accumulated cyclone energy (ACE) is a metric used to compare overall activity of tropical cyclones, utilizing the available records of windspeeds at six-hour intervals to synthesize storm duration and strength into a single index value. The ACE index may refer to a single storm or to groups of storms such as those within a particular month, a full season or combined seasons. It is calculated by summing the square of tropical cyclones' maximum sustained winds, as recorded every six hours, but only for windspeeds of at least tropical storm strength (≥ 34 kn; 63 km/h; 39 mph); the resulting figure is divided by 10,000 to place it on a more manageable scale.

The calculation originated as the Hurricane Destruction Potential (HDP) index, which sums the squares of tropical cyclones' maximum sustained winds while at hurricane strength, at least 64 knots (≥ 119 km/h; 74 mph) at six-hour recorded intervals across an entire season. The HDP index was later modified to further include tropical storms, that is, all wind speeds of at least 34 knots (≥ 63 km/h; 39 mph), to become the accumulated cyclone energy index.

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Tropical cyclones in the context of Middle latitudes

The middle latitudes, also called the mid-latitudes (sometimes spelled midlatitudes) or moderate latitudes, are spatial regions on either hemisphere of Earth, located between the Tropic of Cancer (latitude 23°26′09.3″) and the Arctic Circle (66°33′50.7″) in the Northern Hemisphere and between the Tropic of Capricorn (-23°26′09.3″) and the Antarctic Circle (-66°33′50.7″) in the Southern Hemisphere. They include Earth's subtropical and temperate zones, which lie between the two tropics and the polar circles. Weather fronts and extratropical cyclones are usually found in this area, as well as occasional tropical cyclones or subtropical cyclones, which have traveled from their areas of formation closer to the Equator.

The prevailing winds in the middle latitudes are often very strong. These parts of the world also see a wide variety of fast-changing weather as cold air masses from the poles and warm air masses from the tropics constantly push up and down over them against each other, sometimes alternating within hours of each other, especially in the roaring forties (latitudes between 40° and 50° in both hemispheres), even though the winds on the Northern Hemisphere are not as strong as in the Southern Hemisphere, due to the large landmasses of North America, Europe and Asia.

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Tropical cyclones in the context of Bermuda

Bermuda is a British Overseas Territory in the North Atlantic Ocean. The closest land outside the territory is in the U.S. state of North Carolina, about 1,035 km (643 mi) to the west-northwest.

Bermuda is an archipelago consisting of 181 islands, although the most significant islands are connected by bridges and appear to form one landmass. It has a land area of 54 square kilometres (21 sq mi). Bermuda has a tropical climate, with warm winters and hot summers. Its climate also exhibits oceanic features similar to other coastal areas in the Northern Hemisphere with warm, moist air from the ocean ensuring relatively high humidity and stabilising temperatures. Bermuda is prone to severe weather from recurving tropical cyclones; however, it receives some protection from a coral reef and its position north of the Main Development Region, which limits the direction and severity of approaching storms.

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Tropical cyclones in the context of 2012 Atlantic hurricane season

The 2012 Atlantic hurricane season was the final year in a string of three consecutive very active seasons since 2010, with 19 tropical storms. The 2012 season was also a costly one in terms of property damage, mostly due to Hurricane Sandy. The season officially began on June 1 and ended on November 30, dates that conventionally delimit the period during each year in which most tropical cyclones form in the Atlantic Ocean. However, Alberto, the first named system of the year, developed on May 19 – the earliest date of formation since Subtropical Storm Andrea in 2007. A second tropical cyclone, Beryl, developed later that month. This was the first occurrence of two pre-season named storms in the Atlantic basin since 1951. It moved ashore in North Florida on May 29 with winds of 65 mph (105 km/h), making it the strongest pre-season storm to make landfall in the Atlantic basin. This season marked the first time since 2009 where no tropical cyclones formed in July. Another record was set by Hurricane Nadine later in the season; the system became the fourth-longest-lived tropical cyclone ever recorded in the Atlantic, with a total duration of 22.25 days. The final storm to form, Tony, dissipated on October 25, and the season came to a close when Hurricane Sandy became extratropical on October 29.

Pre-season forecasts by the Colorado State University (CSU) called for a below average season, with 10 named storms, 4 hurricanes, and 2 major hurricanes. The National Oceanic and Atmospheric Administration (NOAA) issued its first outlook on May 24, predicting a total of 9–15 named storms, 4–8 hurricanes, and 1–3 major hurricanes; both agencies noted the possibility of an El Niño, which limits tropical cyclone activity. Following two pre-season storms, the CSU updated their forecast to 13 named storms, 5 hurricanes, and 2 major hurricanes, while the NOAA upped their forecast numbers to 12–17 named storms, 5–8 hurricanes, and 2–3 major hurricanes on August 9. Despite this, activity far surpassed the predictions.

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Tropical cyclones in the context of Japan Meteorological Agency

The Japan Meteorological Agency (Japanese: 気象庁, Hepburn: Kishō-chō; JMA) is a division of the Ministry of Land, Infrastructure, Transport and Tourism dedicated to the scientific observation and research of natural phenomena. Headquartered in Minato, Tokyo, the agency collects data on meteorology, hydrology, seismology, volcanology, and other related fields.

The JMA is responsible for collecting and disseminating weather data and forecasts to the public, as well as providing specialized information for aviation and marine sectors. Additionally, the JMA issues warnings for volcanic eruptions and is integral to the nationwide Earthquake Early Warning (EEW) system. As one of the Regional Specialized Meteorological Centers designated by the World Meteorological Organization (WMO), the JMA also forecasts, names, and distributes warnings for tropical cyclones in the Northwestern Pacific region. This includes areas such as the Celebes Sea, the Sulu Sea, the South China Sea, the East China Sea, the Yellow Sea, the Sea of Japan, and the Sea of Okhotsk.

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Tropical cyclones in the context of Santa Rosa Island (Florida)

30°22′57″N 86°51′23″W / 30.38250°N 86.85639°W / 30.38250; -86.85639Santa Rosa Island is a 40-mile (64 km) barrier island located in the U.S. state of Florida, thirty miles (48 km) east of the Alabama state border. The communities of Pensacola Beach, Navarre Beach, and Okaloosa Island are located on the island. On the northern side of the island, are Pensacola Bay on the west (see map) and Choctawhatchee Bay on the east, joined through Santa Rosa Sound.

Santa Rosa Island has weathered numerous hurricanes and other tropical cyclones, including the hurricane of September 1559, Hurricane Erin and Hurricane Opal (both in 1995), Hurricane Ivan (2004), Hurricane Dennis (2005), Tropical Storm Claudette (2009), and the remnants of Hurricane Ida (2009).

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