title: Datu

text: In some cases, such as the more developed "sakop" or "kinadatuan" in the Visayas (e.g., Panay, Bohol and Cebu), origin myths and other folk narratives firmly placed the datu and the aristocratic class at the top of a divinely sanctioned and stable social order. These folk narratives portrayed the ancestors of datus and other nobles as being created by an almighty deity, just like other human beings. But the behavior of these creations determined the social position of their descendants.


title: Datu

text: This conception of social organization even continues to shape Philippine society today despite the introduction of western, externally democratic structures. This has led some sociologists and political scientists to describe the Philippines' political structure as a cacique democracy.


title: Datu

text: The "authority, power, and influence" of the datu ("adjali") emanated primarily from his recognized status within the noble class.


title: Datu

text: Noble birth was not the only factor that determined a datu's political legitimacy, however. Success as a datu was dependent on one's "personal charisma, prowess in war, and wealth."


title: Datu

text: The office of "datu" was normally passed on through heredity, and even in cases where it was not passed on through direct descent, only a fellow member of the aristocratic class could ascend to the position. In large settlements (called "bayan" among the Tagalogs) in which several datus and their barangays lived in close proximity, paramount datus were chosen by datus from amongst themselves in a more democratic way, but even this position as most senior among datus was often passed on through heredity.


title: Datu

text: Antonio de Morga, in his work "Sucesos de las Islas Filipinas", expounded on this succession through heredity, noting:


title: Datu

text: Since the culture of the pre-colonial societies in the Visayas, northern Mindanao, and Luzon were largely influenced by Hindu and Buddhist cultures, the datus who ruled these principalities (such as Butuan Calinan, Ranau Gandamatu, Maguindanao Polangi, Cebu, Bohol, Panay, Mindoro and Manila) also share the many customs of royalties and nobles in Southeast Asian territories (with Hindu and Buddhist cultures), especially in the way they used to dress and adorn themselves with gold and silk. The Boxer Codex bears testimony to this fact. The measure of the prince's possession of gold and slaves was proportionate to his greatness and nobility. The first Westerners, who came to the archipelago, observed that there was hardly any "Indian" who did not possess chains and other articles of gold.


title: Datu

text: The Spanish colonizers who came in the 1500s acknowledged the nobility of the aristocratic class within early Philippine societies. Morga, for example, referred to them as "principalities".


title: Datu

text: Once the Spanish colonial government had been established, the Spanish continued to recognize the descendants of pre-colonial datus as nobles, assigning them positions such as Cabeza de Barangay. Spanish monarchs recognized their noble nature and origin.


title: Datu

text: When travelers – whether traders or colonizers – came to the Philippines from cultures which were under a sovereign monarch, these travelers often initially referred to the rulers of Philippine polities as "monarchs", implying recognition of their powers as sovereigns.


title: Datu

text: Some early examples were the Song dynasty traders who came to the Philippines and referred to the ruler of Ma-i as a "huang", meaning "king" – an appellation later adopted by the Ming dynasty courts when dealing with the Philippine archipelago cultures of their own time, such as Botuan and Luzon.


title: Datu

text: Later, the Spanish expeditions of Ferdinand Magellan (in the 1520s) and Miguel López de Legazpi (in the 1570s) initially referred to paramount datus (lakans, rajahs, sultans, etc.) as "kings", although the Spanish stopped using this term when the Spanish under the command of Martin de Goiti first forayed out towards the polities in Bulacan and Pampanga in late 1571 and realized that these Kapampanan datus had a choice not to obey the wishes of the paramount datus of Tondo (Lakandula) and Maynila (Rajahs Matanda and Sulayman), leading Lakandula and Sulayman to explain that there was "no single king over these lands", and that the influence of Tondo and Maynila over the Kapampangan polities did not include either territorial claim or absolute command.


title: Datu

text: Junker and Scott note that this misconception was natural, because both the Chinese and the Spanish came from cultures which had autocratic and imperial political structures. It was a function of language, since their respective sinocentric and hispanocentric vocabularies were organized around worldviews which asserted the divine right of monarchs. As a result, they tended to project their beliefs into the peoples they encountered during trade and conquest.


title: Datu

text: The concept of a sovereign monarchy was not unknown among the various early polities of the Philippine archipelago, since many of these settlements had rich maritime cultures and traditions, and traveled widely as sailors and traders. The Tagalogs, for example had the word "hari" to describe a monarch. As noted by "Fray" San Buenaventura (1613, as cited by Junker, 1990 and Scott, 1994), however, the Tagalogs only applied "hari" (king) to foreign monarchs, such as those of the Javanese Madjapahit kingdoms, rather than to their own leaders. "Datu", "rajah", "lakan", etc., were distinct unique words to describe the powers and privilege of indigenous or local rulers and paramount rulers.


title: Datu

text: Although early Philippine datus, lakans, rajahs, sultans, etc., were not sovereign in the political or military sense, they later came to be referred to as such due to the introduction of European literature during the Spanish colonial period.


title: Datu

text: Because of the cultural and political discontinuities that came with colonization, playwrights of Spanish-era Philippine literature such as "comedias" and "zarzuelas" did not have precise terminologies to describe former Philippine rulership structures, and began appropriating European concepts, such as "king" or "queen" to describe them. Because most Filipinos, even during precolonial times, related with political power structures as outsiders, this new interpretation of "royalty" was accepted in the broadest sense, and the distinction between monarchy as a political structure vis a vis membership in a hereditary noble line or dynasty, was lost.


title: Datu

text: This much-broader popular conception of monarchy, built on Filipino experiences of "great men" being socially separate from ordinary people rather than the hierarchical technicalities of monarchies in the political sense, persists today. Common Filipino experience does not usually draw distinctions between aristocracy and nobility vis a vis sovereignty and monarchy. Datus, lakans, rajahs, sultans, etc., are thus referred to as kings or monarchs in this non-technical sense, particularly in 20th century Philippine textbooks.


title: Datu

text: The technical distinction between these concepts have only recently been highlighted again, by ethnohistorians, historiographers and anthropologists belonging to the critical scholarship tradition, since their concern is to capture indigenous meanings in the most accurate way possible.


title: Datu

text: Still this assessment of the nature of pre-colonial polities has to be viewed in the context of plurality of pre-colonial social structures existing in the archipelago. It is obvious that those which existed in Luzon, vary from those that existed in the Visayas and Mindanao.


title: Datu

text: Also, the views of the various authors have to be assessed taking into consideration the background of social constructs, from which they assess the local pre-colonial polities. The historical, politico-cultural and chronological distance of these authors from actual events in the lives of the Filipino pre-colonials has to be taken into consideration. The view of an author living in the 20th century democratic country has a lot of difference from those who came from monarchic societies, who had actual contact with the pre-colonials, and who tried to qualify and approximate the conventions used in local hierarchical structures using the constructs of their time and context, in order to understand their actual experience of contact with what existed in the archipelago during the 16th century.


title: Datu

text: The title of "Honorary Datu" has also been conferred to certain foreigners and non-tribe members by the heads of local tribes and Principalities of ancient origin. During the colonial period, some of these titles carried with them immense legal privileges. For example, on January 22, 1878, Sultan Jamalul A'Lam of Sulu appointed the Baron de Overbeck (an Austrian who was then the Austro-Hungarian Empire's consul-general in Hong Kong) as Datu Bendahara and as rajah of Sandakan, with the fullest power of life and death over all the inhabitants. On the other hand, in the Philippines, the Spaniards did not practice the granting of honorary titles. Instead, they created nobiliary titles over conquered territories in the archipelago, in order to reward high Spanish colonial officials. These nobiiary titles are still used in Spain until now by the descendants of the original holders, e.g., Count of Jolo. At present, arrangements such as this can no longer carry similar legal bearing under the Philippine laws.


title: Datu

text: The various tribes and claimants to the royal titles of certain indigenous peoples in the Philippines have their own particular or personal customs in conferring local honorary titles, which correspond to the specific and traditional social structures of some indigenous peoples in the country.


title: Datu

text: The present-day claimants of the precolonial royal/noble title and rank of "datu" are of two types. The descendants of rulers of Islamic precolonial polities in Mindanao, and the descendants of the Christianized datus. This second group are those that live in the predominantly Catholic mainstream Filipino society. They are:


title: Datu

text: In the mainstream Philippine society that is overwhelmingly Catholic, the descendants of the "principalía" are the rightful claimants of the ancient sovereign royal and noble ranks of the pre-conquest kingdoms, principalities, and barangays of their ancestors (e.g., the realm of the Christianized last datu of the Cuyunin tribes). These descendants of the ancient ruling class are now among the landed aristocracy, intellectual elite, merchants, and politicians in the contemporary Filipino society. These people have had ancestors holding the titles of ""Don"" or ""Doña"", which were also used by Spanish royalties and nobilities during the Spanish colonial period, and still use at present.


title: Datu

text: Article VI, Section 31 of the 1987 Constitution explicitly forbids the creation, granting, and use of new royal or noble titles. Titles of "Honorary Datu" conferred by various ethnic groups to certain foreigners and non-tribe members by local chieftains are only forms of local award or appreciation for some goods or services done to a local tribe or to the person of the chieftain, and are not legally binding. Any contrary claim is otherwise unconstitutional under Philippine law.


title: Datu

text: However, through the Indigenous Peoples' Rights Act of 1997, the republic also protects the peculiar situation of tribal minorities and their traditional indigenous social structures. This special law allows members of indigenous minority tribes to be conferred with traditional leadership titles, including the title "datu", in a manner specified under the law's implementing rules and guidelines (Administrative Order No. 1, Series of 1998, of the National Commission on Indigenous Peoples specifically under Rule IV, Part I, Section 2, a-c), which reads:


title: Datu

text: From the above-mentioned ordinance of the National Commission on Indigenous Peoples, the current usage of the title "datu" for newly created offices of leadership of tribal minorities does not accord nobility, which is forbidden by the Constitution of the republican state.


title: Datu

text: The "fons honorum" (source of honor) in the modern Philippine state is the sovereign Filipino people, who are equal in dignity under a democratic form of government. The Philippine government grants state honors and decorations, and through the system of awards and decorations of its Armed Forces of the Philippines and the Philippine National Police. These honors do not grant or create titles of royalty or nobility, in accordance with the Constitution.


title: Datu

text: Deducing from the theory of Jean Bodin (1530–1596), a French jurist and political philosopher, it could be said that ancient Filipino royalties, who never relinquished their sovereign rights by voluntary means (according to opinions of some historians), of whom the sovereign powers over their territories ("de facto" sovereignty) passed on to the Spanish "jura regalia" through some disputed means, retain their ""fons honorum"" as part of their "de jure" sovereignty. Therefore, as long as the blood is alive in the veins of these royal houses, "de jure" sovereignty is alive as well – which means they can still bestow titles of nobility. However, the practical implications of this claim is unclear, e.g., in the case of usurpation of titles by other members of the bloodline.


title: Datu

text: Heads of dynasties (even the deposed ones) belong to one of the three kinds of sovereignty that has been existing in human society. The other two are heads of states (of all forms of government, e.g., monarchy, republican, communist, etc.) and traditional heads of the Church (both Roman Catholic and Orthodox). The authority that emanates from this last type is transmitted through an authentic apostolic succession, i.e., direct lineage of ordination and succession of office from the Apostles (from St. Peter, in case of the supreme pontiff of the Roman Catholic Church – the pope).


title: Datu

text: These sovereign authorities exercise the following sovereign rights and powers: "ius imperii" (the right to command and rule a territory or a juridical entity), "ius gladii" (the right to impose obedience through command and also control armies), "ius majestatis" (the right to be honored and respected according to one's title), and "ius honorum" (the right to award titles, merits and rights). Considering the theory of Jean Bodin, that ""Sovereignty is one and indivisible, it cannot be delegated, sovereignty us irrevocable, sovereignty is perpetual, sovereignty is a supreme power"", one can argue about the rights of deposed dynasties, also as "fons honorum". It can be said that their "ius honorum" depends on their rights as a family, and does not depend on the authority of the "de facto" government of a state. This is their "de jure" right. Even though it is not a "de facto" right, it is still a right.


title: Datu

text: But again, in case of conflict of norms on "fons honorum" in actual situations, the legislations of the "de facto" sovereign authority have precedence. All others are abrogated, unless otherwise recognized under the terms of such "de facto" authority.


title: Datu

text: This is the view to reconsider when we study sovereignty based on the political impact of the 1987 Constitution of the Republic of the Philippines to the some polities that have been existing since the pre-colonial period, e.g., the Sultanate of Sulu and the Sultanate of Maguindanao.


title: Ripsaw (vehicle)

text: The Ripsaw is a series of developmental unmanned ground combat vehicles designed by Howe & Howe Technologies (now part of Textron Systems) for evaluation by the United States Army.


title: Ripsaw (vehicle)

text: The Howe brothers started the Ripsaw as a small family project in 2000. They introduced it at a Dallas vehicle show in 2001, where it caught the interest of the U.S. Army. Later that year the U.S. military ordered a prototype MS-1 to be made and shipped to Iraq.


title: Ripsaw (vehicle)

text: The Ripsaw is intended to perform various missions including convoy protection, perimeter defense, surveillance, rescue, border patrol, crowd control, and explosive ordnance disposal. For perimeter defense or crowd control, a belt of M5 crowd control munitions (MCCM) can be mounted around the vehicle to break up crowds or engage personnel with less-lethal flash-bang effects and rubber bullets. Cameras provide 360-degree coverage for situational awareness for the operator.


title: Ripsaw (vehicle)

text: The Army has tested the Ripsaw while remote-controlled by a soldier in another armored vehicle up to away. Its weapon system is modified to fire remotely using the Advanced Remote Armament System (ARAS), a gun that loads its own ammunition and can swap out various types of ammunition, such as lethal and less-lethal, in just a few seconds. These capabilities allow manned vehicles to send the Ripsaw out in front of them and engage targets without exposing soldiers to threats. As of March 2017, the Army was still testing the vehicle as an unmanned platform to test remote controlled weapon stations.


title: Ripsaw (vehicle)

text: In October 2019, Textron and Howe & Howe unveiled their Ripsaw M5 vehicle, and on 9 January 2020, the U.S. Army awarded them a contract for the Robotic Combat Vehicle-Medium (RCV-M) program. Four Ripsaw M5 prototypes are to be delivered and used in a company-level to determine the feasibility of integrating unmanned vehicles into ground combat operations in late 2021. It can reach speeds of more than , has a combat weight of 10.5 tons and a payload capacity of . The RCV-M is armed with a 30 mm autocannon and a pair of anti-tank missiles. The standard armor package can withstand 12.7×108mm rounds, with optional add-on armor increasing weight to up to 20 tons. If disabled, it will retain the ability to shoot, with its sensors and radio uplink prioritized to continue transmitting as its primary function.


title: Texas hold 'em starting hands

text: In Texas hold 'em, a starting hand consists of two hole cards, which belong solely to the player and remain hidden from the other players. Five community cards are also dealt into play. Betting begins before any of the community cards are exposed, and continues throughout the hand. The player's "playing hand", which will be compared against that of each competing player, is the best 5-card poker hand available from his two hole cards and the five community cards. Unless otherwise specified, here the term "hand" applies to the player's two hole cards, or "starting hand".


title: Texas hold 'em starting hands

text: There are 1326 distinct possible combinations of two hole cards from a standard 52-card deck in hold 'em, but since suits have no absolute value in this poker variant, many of these hands are identical in value before the flop. For example, and are identical in value, because each is a hand consisting of an ace and a jack of the same suit.


title: Texas hold 'em starting hands

text: Therefore, there are 169 non-equivalent starting hands in hold 'em, which is the total count of 13 pocket pairs, 13 × 12 x 1 / 2 = 78 suited hands and likewise 78 unsuited hands (13 + 78 + 78 = 169).


title: Texas hold 'em starting hands

text: These 169 hands are "not" equally likely. Hold 'em hands are sometimes classified as having one of three "shapes":


title: Texas hold 'em starting hands

text: There are 13 cards per suit, and one is in your hand leaving 12 remaining of the 51 cards remaining in the deck. 12/51=.2353 or 23.5%


title: Texas hold 'em starting hands

text: It is typical to abbreviate suited hands in hold 'em by affixing an "s" to the hand, as well as to abbreviate non-suited hands with an "o" (for offsuit). That is,


title: Texas hold 'em starting hands

text: Some notable theorists and players have created systems to rank the value of starting hands in limit Texas hold'em. These rankings do not apply to no limit play.


title: Texas hold 'em starting hands

text: David Sklansky and Mason Malmuth assigned in 1999 each hand to a group, and proposed all hands in the group could normally be played similarly. Stronger starting hands are identified by a lower number. Hands without a number are the weakest starting hands. As a general rule, books on Texas hold'em present hand strengths starting with the assumption of a nine or ten person table. The table below illustrates the concept:


title: Texas hold 'em starting hands

text: The "Chen Formula" is a way to compute the "power ratings" of starting hands that was originally developed by Bill Chen.


title: Texas hold 'em starting hands

text: In poker communities, it is common for hole cards to be given nicknames. While most combinations have a nickname, stronger handed nicknames are generally more recognized, the most notable probably being the "Big Slick" - Ace and King of the same suit, although an Ace-King of any suit combination is less occasionally referred to as an Anna Kournikova, derived from the initials AK and because it "looks really good but rarely wins." Hands can be named according to their shapes (e.g., paired aces look like "rockets", paired jacks look like "fish hooks"); a historic event (e.g., A's and 8's - dead man's hand, representing the hand held by Wild Bill Hickok when he was fatally shot in the back by Jack McCall in 1876); many other reasons like animal names, alliteration and rhyming are also used in nicknames.


title: Apple File System

text: Apple File System (APFS) is a proprietary file system developed and deployed by Apple Inc. for macOS Sierra (10.12.4) and later, iOS 10.3 and later, tvOS 10.2 and later, watchOS 3.2 and later, and all versions of iPadOS. It aims to fix core problems of HFS+ (also called Mac OS Extended), APFS's predecessor on these operating systems. APFS is optimized for solid-state drive storage and supports encryption, snapshots, and increased data integrity, among other capabilities.


title: Apple File System

text: Apple File System was announced at Apple's developers conference (WWDC) in June 2016 as a replacement for HFS+, which had been in use since 1998. APFS was released for 64-bit iOS devices on March 27, 2017, with the release of iOS 10.3, and for macOS devices on September 25, 2017, with the release of macOS 10.13.


title: Apple File System

text: Apple released a partial specification for APFS in September 2018 which supported read-only access to Apple File Systems on unencrypted, non-Fusion storage devices. The specification for software encryption was documented later.


title: Apple File System

text: The file system can be used on devices with relatively small or large amounts of storage. It uses 64-bit inode numbers, and allows for more secure storage. The APFS code, like the HFS+ code, uses the TRIM command for better space management and performance. It may increase read-write speeds on iOS and macOS, as well as space on iOS devices, due to the way APFS calculates available data.


title: Apple File System

text: APFS uses the GPT partition scheme. Within the GPT scheme are one or more APFS containers (partition type GUID is ). Within each container there are one or more APFS volumes, all of which share the allocated space of the container, and each volume may have APFS volume roles. macOS Catalina (macOS 10.15) introduced the APFS volume group, which are groups of volumes that Finder displays as one volume. APFS firmlinks lie between hard links and soft links and link between volumes.


title: Apple File System

text: In macOS Catalina the volume role (usually named "Macintosh HD") became read-only, and in macOS Big Sur (macOS 11) it became a signed system volume (SSV) and only volume snapshots are mounted. The volume role (usually named "Macintosh HD - Data") is used as an overlay or shadow of the volume, and both the and volumes are part of the same volume group and shown as one in Finder.


title: Apple File System

text: Clones allow the operating system to make efficient file copies on the same volume without occupying additional storage space. Changes to a cloned file are saved as delta extents, reducing storage space required for document revisions and copies. There is, however, no interface to mark two copies of the same file as clones of the other, or for other types of data deduplication.


title: Apple File System

text: Apple File System natively supports full disk encryption, and file encryption with the following options:


title: Apple File System

text: Apple File System is designed to avoid metadata corruption caused by system crashes. Instead of overwriting existing metadata records in place, it writes entirely new records, points to the new ones and then releases the old ones, an approach known as redirect-on-write. This avoids corrupted records containing partial old and partial new data caused by a crash that occurs during an update. It also avoids having to write the change twice, as happens with an HFS+ journaled file system, where changes are written first to the journal and then to the catalog file.


title: Apple File System

text: APFS supports transparent compression on individual files using Deflate (Zlib), LZVN (libFastCompression), and LZFSE. All three are Lempel-Ziv-type algorithms. This feature is inherited from HFS+, and is implemented with the same AppleFSCompression / decmpfs system using resource forks or extended attributes. As with HFS+, the transparency is broken for tools that do not use decmpfs-wrapped routines.


title: Apple File System

text: APFS adds the ability to have multiple logical drives (referred to as volumes) in the same container where free space is available to all volumes in that container (block device).


title: Apple File System

text: While APFS includes numerous improvements relative to its predecessor, HFS+, a number of limitations have been noted.


title: Apple File System

text: APFS does not provide checksums for user data. It also does not take advantage of byte-addressable non-volatile random-access memory.


title: Apple File System

text: Enumerating files, and any inode metadata in general, is much slower on APFS when it is located on a hard disk drive. This is because instead of storing metadata at a fixed location like HFS+ does, APFS stores them alongside the actual file data. This fragmentation of metadata means more seeks are performed when listing files, acceptable for SSDs but not HDDs.


title: Apple File System

text: Unlike HFS+, APFS does not support hard links to directories. Since the version of the Time Machine backup software included in Mac OS X 10.5 (Leopard) through macOS 10.15 (Catalina) relied on hard links to directories, APFS was initially not a supported option for its backup volumes. This limitation was overcome starting in macOS 11 Big Sur, wherein APFS is now the default file system for new Time Machine backups (existing HFS+-formatted backup drives are also still supported). macOS Big Sur's implementation of Time Machine in conjunction with APFS-formatted drives enables "faster, more compact, and more reliable backups" than were possible with HFS+-formatted backup drives.


title: Apple File System

text: Limited, experimental support for APFS was first introduced in macOS Sierra 10.12.4. Since macOS 10.13 High Sierra, all devices with flash storage are automatically converted to APFS. As of macOS 10.14 Mojave, Fusion Drives and hard disk drives are also upgraded on installation. The primary user interface to upgrade does not present an option to opt out of this conversion, and devices formatted with the High Sierra version of APFS will not be readable in previous versions of macOS. Users can disable APFS conversion by using the installer's codice_1 utility on the command line and passing codice_2.


title: Apple File System

text: FileVault volumes are not converted to APFS as of macOS Big Sur 11.2.1. Instead macOS formats external FileVault drives as CoreStorage Logical Volumes formatted with Mac OS Extended (Journaled). FileVault drives can be optionally encrypted.


title: Apple File System

text: An experimental version of APFS, with some limitations, is available in macOS Sierra through the command line codice_3 utility. Among these limitations, it does not perform Unicode normalization while HFS+ does, leading to problems with languages other than English. Drives formatted with Sierra’s version of APFS may also not be compatible with future versions of macOS or the final version of APFS, and the Sierra version of APFS cannot be used with Time Machine, FileVault volumes, or Fusion Drives.


title: Apple File System

text: iOS 10.3, tvOS 10.2, and watchOS 3.2 convert the existing HFSX file system to APFS on compatible devices.


title: Apple File System

text: Despite the ubiquity of APFS volumes in today's Macs and the format's 2016 introduction, third-party repair utilities continue to have notable limitations in supporting APFS volumes, due to Apple's delayed release of complete documentation. According to Alsoft, the maker of DiskWarrior, Apple's 2018 release of partial APFS format documentation has delayed the creation of a version of DiskWarrior that can safely rebuild APFS disks. Competing products, including MicroMat's TechTool and Prosoft's Drive Genius, are expected to increase APFS support as well.


title: Apple File System

text: Paragon Software Group has published a software development kit under the 4-Clause BSD License that supports read-only access of APFS drives. An independent read-only open source implementation by Joachim Metz, libfsapfs, is released under GNU Lesser General Public License v3. It has been packaged into Debian, Fedora Linux, Rocky Linux, Red Hat Enterprise Linux and Ubuntu software repositories. Both are command-line tools that do not expose a normal filesystem driver interface. There is a Filesystem in Userspace (FUSE) driver for Linux called apfs-fuse with read-only access. An "APFS for Linux" project is working to integrate APFS support into the Linux kernel.


title: Dashboard

text: A dashboard (also called dash, instrument panel (IP), or fascia) is a control panel set within the central console of a vehicle or small aircraft. Usually located directly ahead of the driver (or pilot), it displays instrumentation and controls for the vehicle's operation.


title: Dashboard

text: Originally, the word "dashboard" applied to a barrier of wood or leather fixed at the front of a horse-drawn carriage or sleigh to protect the driver from mud or other debris "dashed up" (thrown up) by the horses' hooves. The first known use of the term (hyphenated as "dash-board", and applied to sleighs) dates from 1847. Commonly these boards did not perform any additional function other than providing a convenient handhold for ascending into the driver's seat, or a small clip with which to secure the reins when not in use.


title: Dashboard

text: When the first "horseless carriages" were constructed in the late 19th century, with engines mounted beneath the driver such as the Daimler Stahlradwagen, the simple dashboard was retained to protect occupants from debris thrown up by the cars' front wheels. However, as car design evolved to position the motor in front of the driver, the dashboard became a panel that protected vehicle occupants from the heat and oil of the engine. With gradually increasing mechanical complexity, this panel formed a convenient location for the placement of gauges and minor controls, and from this evolved the modern instrument panel, although retaining its archaic common name.


title: Dashboard

text: The first mass-produced automobile, the Oldsmobile Curved Dash, got its name from its dashboard, which was curved like that of a sleigh.


title: Dashboard

text: Where the dashboard originally included an array of simple controls (e.g., the steering wheel) and instrumentation to show speed, fuel level and oil pressure, the modern dashboard may accommodate a broad array of gauges, and controls as well as information, climate control and entertainment systems.


title: Dashboard

text: Contemporary dashboards may include the speedometer, tachometer, odometer, engine coolant temperature gauge, and fuel gauge, turn indicators, gearshift position indicator, seat belt warning light, parking-brake warning light, and engine-malfunction lights. Heavy vehicles that feature air brakes, such as trucks and buses will also have gauges to indicate the available air pressure in the braking system. Other features may include a gauge for alternator voltage, indicators for low fuel, low oil pressure, low tire pressure and faults in the airbag (SRS) systems, glove compartment, ashtray and a cigarette lighter or power outletas well as heating and ventilation systems, lighting controls, safety systems, entertainment equipment and information systems, e.g., navigation systems.


title: Dashboard

text: In 1937, Chrysler, Dodge, DeSoto, and Plymouth cars came with a safety dashboard that was flat, raised above knee height, and had all the controls mounted flush.


title: Dashboard

text: Padded dashboards were advocated in the 1930s by car safety pioneer Claire L. Straith. In 1948, the Tucker 48 became the first car with a padded dashboard.


title: Dashboard

text: One of the safety enhancements of the 1970s was the widespread adoption of padded dashboards. The padding is commonly polyurethane foam, while the surface is commonly either polyvinyl chloride (PVC) or leather in the case of luxury models.


title: Dashboard

text: In the 1940s through the 1960s, American car manufacturers and their imitators designed aesthetically shaped instruments on a dashboard accented with chrome and transparent plastic, which could be less readable, but was often thought to be more stylish. Sunlight could cause a bright glare on the chrome, particularly for a convertible. On North American vehicles in particular, this trend lingered on until the late-1980s, which still featured dashboards with wood and fake chrome embellishment along with square instruments - long after European and Japanese manufacturers had long embraced a plainer, more functional and austere approach for dashboard and instrument panel design.


title: Dashboard

text: With the advent of the VFD, LED and LCD in consumer electronics, some manufacturers used instruments with digital readouts to make their cars appear more up to date. Some cars use a head-up display to project the speed of the car onto the windscreen in imitation of fighter aircraft, but in a far less complex display.


title: Dashboard

text: In recent years, spurred on by the growing aftermarket use of dash kits, many automakers have taken the initiative to add more stylistic elements to their dashboards. One prominent example of this is the Chevrolet Sonic which offers both exterior (e.g., a custom graphics package) and interior cosmetic upgrades. In addition to OEM dashboard trim and upgrades a number of companies offer domed polyurethane or vinyl applique dash trim accent kits or "dash kits".


title: Dashboard

text: Manufacturers such as BMW, Honda, Toyota and Mercedes-Benz have included fuel-economy gauges in some instrument clusters, showing fuel mileage in real time, which was limited mainly to luxury vehicles and later, hybrids. Following a focus on increasing fuel economy in the late 2000s along with increased technology, most vehicles in the 2010s now come with either real-time or average mileage readouts on their dashboards. The ammeter was the gauge of choice for monitoring the state of the charging system until the 1970s. Later it was replaced by the voltmeter. Today most family vehicles have warning lights instead of voltmeters or oil pressure gauges in their dashboard instrument clusters, though sports cars often have proper gauges for performance purposes and driver appeasement along with larger trucks, mainly to monitor system function during heavy usage such as towing or off-road usage.


title: Super Mario Maker

text: Upon release, critical reviews praised its user interface and course editing tools. By May 2016, more than seven million courses had been created by players worldwide, which had been played more than 600 million times. was released in December 2016. "Super Mario Maker 2" was released for the Nintendo Switch in June 2019. On November 25, 2020, Nintendo formally announced that course upload support would be discontinued on March 31, 2021 and that sale of the game on the Wii U's Nintendo eShop would be discontinued on January 12, 2021. The "Super Mario Maker" bookmark portal site was discontinued on January 13, 2021.


title: Super Mario Maker

text: "Super Mario Maker" allows players to create levels in the style of the "Super Mario" series, and publish them to the Internet for other players. The courses are based on the gameplay and visual style of "Super Mario Bros.", "Super Mario Bros. 3", "Super Mario World", and "New Super Mario Bros. U", which all share the physics of the latter. The gameplay mechanics and enemy behavior vary between game modes. Some elements are limited to specific game styles, and other elements can be merged into other game styles, such as having Boos in "Super Mario Bros."


title: Super Mario Maker

text: In addition to traditional "Mario" elements such as Goombas, warp pipes, and power ups, players can uniquely manipulate the behavior of elements. For example, enemies can be stacked, hazards can emerge from question blocks and warp pipes, shells can be worn as protective helmets, and cannons can emit chosen objects. These new combinations are enabled by editing tools working in tandem. Players can enlarge an enemy with a Super Mushroom, give an enemy a pair of flying wings, combine different attributes, and more. The Soundfrog adds audiovisual effects, though microphone-recorded sounds are removed from uploaded courses. New editing elements are unlocked gradually across nine days of course creation. The Mystery Mushroom, exclusive to the "Super Mario Bros." theme, has the power-up of a Super Mushroom and dresses Mario in one of about 150 costumes. Each of these costumes can be unlocked by playing through the 100 Mario Challenge, by clearing special Event Courses, or by scanning a corresponding Amiibo figurine. The 8-bit Mario figurine adds a Big Mushroom that makes Mario giant while making enemies look like Mario, with hats and mustaches.


title: Super Mario Maker

text: After a created course is played to completion, it is then allowed to be published to the online Course World. There, all players can browse and play various user-generated courses, or participate in the 100 Mario Challenge with a set of randomly selected user-created courses with 100 lives. Alternatively, players can play the 10 Mario Challenge, with a selection of pre-made courses and only 10 lives. Players are initially limited in the number of uploadable courses, but by receiving stars from other players, they can earn medals which allow them to upload more courses.


title: Super Mario Maker

text: Before developing "Super Mario Maker", Nintendo had previously explored the concept of a video game editor in the 1990s. The company filed a patent in 1994, for console hardware allowing players to pause a game, edit parts of the game, resume gameplay, and to save and share the changes. "Super Mario Maker" was conceived as a tool for Nintendo's internal development team to make "Mario" levels. The team, however, quickly realized the tool's potential as a standalone game and pitched the idea to senior game designer Takashi Tezuka. Meanwhile, Tezuka had been wanting to make a Wii U follow-up to "Mario Paint" that utilizes the Wii U GamePad. Upon seeing the "Super Mario Maker" tool, Tezuka realized that a course-making tool was more marketable than a mere art program. He noted to "Polygon" that building courses is "not as difficult or out of reach as drawing is" but that he "was inspired to bring the fun of "Mario Paint" into this course editor". This game is the directorial debut of Yosuke Oshino, who previously worked as a programmer on "Pikmin", "Pikmin 2", and "New Super Mario Bros. Wii". The game's soundtrack was composed and arranged by Koji Kondo, Naoto Kubo, and Asuka Hayazaki.


title: Super Mario Maker

text: The game was announced at E3 2014 with the title ""Mario Maker"". Although first revealed officially via Nintendo's E3 Presentation on June 10, rumors of that title began earlier that month after a photo was taken of Nintendo's incomplete trade show booth which prominently featured the title. The game was rebranded as ""Super Mario Maker"" at E3 2015 during the Nintendo World Championships.


title: Super Mario Maker

text: Prior to release, Nintendo allowed customers to play "Mario Maker" at Best Buy stores across North America on June 17 and 20, 2015. It was demonstrated with a new name, "Super Mario Maker", on June 14, 2015, during the final round of the Nintendo World Championships event preceding E3 2015. The four courses created by Nintendo Treehouse for the Championships are playable in the final game.


title: Super Mario Maker

text: Nintendo partnered with Facebook to host a special "hackathon" event. 150 Facebook employees were tasked with constructing courses using "Super Mario Maker", and the winning team created a course to be featured in the game on its launch. Several notable video game designers showcased courses they had created, such as Michel Ancel, Koji Igarashi, Tim Rogers, and Derek Yu. Ancel's course is included in the base game as an Event Course.


title: Super Mario Maker

text: "Super Mario Maker" was released worldwide in September 2015, with a corresponding Wii U bundle. Each copy of the game is packaged with a 96-page booklet of creative ideas, which is also a PDF download. Nintendo concurrently launched an 8-bit Mario Amiibo figurine, in two different color variations. The figurine is packaged alone, and within particular "Super Mario Maker" game bundles. A downloadable, "Super Mario Maker"-themed stage for "Super Smash Bros. for Nintendo 3DS" and "Wii U" was released on September 30, 2015, and is in the sequel, "Super Smash Bros. Ultimate".


title: Super Mario Maker

text: The game was originally intended to require players to wait each day to unlock new elements, but a launch day patch delivers new elements corresponding to the player's content creation efforts. Destructoid noted that there were many past "Mario" series elements missing from the game, but the game was updated with new features. The first major update, released on November 4, 2015, adds mid-course checkpoints, conditional power-ups, and Event Courses. Clearing certain Event Courses unlocks additional Mystery Mushroom costumes, such as "Super Mario-kun" and "GameCenter CX" presenter Shinya Arino. The game's second major update was released on December 22, 2015, which adds a speedrun leaderboard, and launched the Super Mario Maker Bookmark website, which allows players to browse uploaded courses and bookmark them to play, allowing for easier sharing of courses. The third update adds more Mystery Mushroom costumes that are unlocked by completing Normal- and Expert-level 100 Mario Challenges, and adds Super Expert mode.


title: Super Mario Maker

text: A sequel, "Super Mario Maker 2", was announced in a Nintendo Direct on February 13, 2019. It was released for the Nintendo Switch on June 28, 2019, with a new level theme based on the Wii U game "Super Mario 3D World", new features including slopes and modifiable auto scroll direction, and new enemies, themes, and items.


title: Super Mario Maker

text: On November 25, 2020, Nintendo announced that they were discontinuing support for uploading new courses on March 31, 2021. As a result, the game was removed from the Wii U eShop on January 12, 2021.


title: Super Mario Maker

text: "Super Mario Maker for Nintendo 3DS" was developed by Redmond-based subsidiary Nintendo Software Technology, with some features adapted or removed. It was released for the Nintendo 3DS in Japan on December 1, 2016, in North America and Europe on December 2, and in Australia on December 3. It includes 100 new built-in courses designed by Nintendo. Players can exchange courses online, directly to friends, or through StreetPass.


title: Super Mario Maker

text: "Super Mario Maker" received generally favorable reviews. IGN's Jose Otero praised the game's social elements, including its online features and the 10 Mario Challenge, stating that players would "see a genuine reverence for Mario’s history" in the online modes. He praised the course editor and its user interface, writing that "[n]o matter which style you choose, creating levels is an intimidating task but the well designed interface makes learning easy and intuitive" and that it "gives us a fun, flexible toolbox to build and play Mario courses like never before".


title: Super Mario Maker

text: GameSpot's Justin Haywald praised the course editor, stating that "the mix-and-match nature [of gameplay elements] allows for exciting and anachronistic additions to familiar scenarios". He was disappointed in particular limitations, such as the absence of checkpoints originating "Super Mario World", and the vertical and horizontal limits of stages. He ultimately concluded that "the game won't necessarily turn you into the next Shigeru Miyamoto, but you can almost feel a little bit of that magic rubbing off every time you upload a new creation".


title: Super Mario Maker

text: "Polygon"s Griffin McElroy praised the game, saying he had "a tremendous amount of fun playing, but the way it developed that newfound appreciation for something I've known my whole life was the game's biggest accomplishment".


title: Super Mario Maker

text: The increasingly rich online library of user-generated content has been individually showcased and praised by reviewers, and has been praised by "Mario" series co-creator Takashi Tezuka. He described Nintendo's overall restraint in the gameplay difficulty of its own content, in the interest of mass appeal. He expressed both appreciation and caution for the fact that the users do not necessarily share the same restraint in their creations.


title: Super Mario Maker

text: The game would contribute to a resurgence in the Kaizo community, which creates extremely difficult levels to test patience and skill.


title: Super Mario Maker

text: Many players criticized Nintendo for removing their online courses without warning or explanation. Patrick Klepek of Kotaku wrote that Nintendo should have made sure anyone creating levels for the game was aware of the company's strict policies regarding level creation so they would know what Nintendo would not find acceptable.


title: Super Mario Maker

text: "Super Mario Maker" debuted in Japan with more than 138,000 physical copies sold; it had sales of 245,000 copies in its first three weeks, by the end of September 2015. It was the second best-selling game in the UK in its first week of release, debuting at No. 2 on the UK software retail chart. It was the fourth fastest-selling game for the Wii U since the console's debut in 2012. In its first three weeks on sale in North America, 445,000 copies had been sold, with over 500,000 sold by the end of September 2015. Sales in the United States reached 1 million in mid-January 2016, making it the sixth Wii U game to do so in the country. By March 2021, 4.02 million copies had been sold worldwide. The Nintendo 3DS version had 162,180 copies sold within its first week of release in Japan. As of December 23, 2016, the Nintendo 3DS version had 448,160 copies sold in the region. As of December 31, 2016, 2 million copies had been sold for 3DS. By the end of March 2017, total 3DS sales reached 2.34 million.


title: Super Mario Maker

text: In May 2016, Nintendo announced that more than 7.2 million courses had been created worldwide, which had been played more than 600 million times.


title: Miomir Kecmanović

text: Miomir Kecmanović (, ; born 31 August 1999) is a Serbian professional tennis player. Kecmanović reached his best singles ranking of world No. 28 on 24 October 2022 and he peaked at world No. 161 on 16 September 2019 in the doubles rankings. He has won one singles and one doubles ATP title, as well as two Challenger titles in his career.


title: Miomir Kecmanović

text: In December 2015, Kecmanović won the Orange Bowl in a 3-set match against Stefanos Tsitsipas from Greece, 6–3, 2–6, 7–6. He reached the final in singles at 2016 Junior US Open where he was defeated by Canadian Félix Auger-Aliassime. He finished the year 2016 as ITF Juniors number 1 ranked tennis player.


title: Miomir Kecmanović

text: Kecmanović was a fifth (reserve) player on a Serbian Davis Cup team in their quarterfinal tie against Great Britain in the 2016 Davis Cup – a standard practice of Tennis Federation of Serbia for each tie to invite a different talented young player to practice with regular players and gain necessary experience. Kecmanović credited this experience for finishing the year as junior world No. 1 and said that he is looking forward to one day make the team and play for Serbia.


title: Miomir Kecmanović

text: In January 2017, Kecmanović won his first singles ITF pro circuit title in Sunrise, Florida, US. In March, he received a wild card entry for the qualifying draw at Miami Masters and defeated 22nd seed and world No. 117 Henri Laaksonen in straight sets in the first round, before losing the deciding qualifying match to 11th seed and world No. 114 Lukáš Lacko. Serbian Davis Cup captain, Nenad Zimonjić, planned to include Kecmanović as a fifth player for Serbia's 7–9 April Davis Cup quarterfinal tie versus Spain, but as Kecmanović received a wild card for Panamá Cup Challenger, he instead chose to play in his first career challenger and lost in the first round to top seed and world No. 86 Horacio Zeballos in 3 sets, 6–2, 4–6, 2–6. He next played in San Luis Potosí Challenger in Mexico and had his first wins on the Challenger level after defeating 3rd seed and world No. 135 Stefan Kozlov in straight sets, Emilio Gómez in three sets and 7th seed Marcelo Arévalo in straight sets, before losing in the semifinals to 8th seed Adrián Menéndez-Maceiras. At Sarasota Kecmanović played in his third successive challenger, losing in the second round to 7th seed and world No. 114 Laaksonen. Kecmanović received a wild card for the qualifying draw of another ATP tournament, Istanbul Open, where he defeated 2nd seed Mirza Bašić in the opening round, but lost to 8th seed Daniel Brands in the deciding qualifier.


title: Miomir Kecmanović

text: Between May and July, Kecmanović played in four futures tournaments in Turkey and Belgium, respectively, winning two and reaching another final and one semifinal. He then resumed playing in challengers, playing three in Asia, with the best result coming in August in Chengdu, where he was stopped in the quarterfinals. In September, Kecmanović was again in the plans to be a fifth player in 15–17 September Davis Cup semifinal against France, but as he received a wildcard for Banja Luka Challenger, he chose to play it in order to improve his ATP ranking, and again lost in the first round. He next played three futures in Italy, getting to one semifinal and two quarterfinals. He finished the season playing in three challengers in China and had his biggest achievement to date in October in Suzhou, when he won the first challenger title of his career by beating 3rd seed and world No. 113 Radu Albot, 6–4, 6–4, in the final.


title: Miomir Kecmanović

text: After reaching two quarterfinals in three challengers to start the season, Kecmanović broke into the top 200 for the first time in his career on February 5, when he was ranked 194th on the ATP list. In March, he made his ATP main draw debut when he was granted wild card for Miami Masters, losing to Denis Istomin in the first round. In April, he defeated 4th seed Michael Mmoh and 6th seed Dennis Novikov in the qualifying rounds to reach the main draw of U.S. Men's Clay Court Championships ATP 250 event in Houston, where he lost to 7th seed Ryan Harrison in the first round.


title: Miomir Kecmanović

text: In July and August, Kecmanović played World TeamTennis league and helped Springfield Lasers win its first ever championship after losing five times in the finals between 1999 and 2014. They defeated Philadelphia Freedoms, 19–18 in the final, after Kecmanović rallied from a 1–3 deficit in the final set to defeat Kevin King, 5–3, and earn Finals MVP honors.


title: Miomir Kecmanović

text: On the strength of three semifinal and one quarterfinal appearance in challenger events in September and October, Kecmanović reached the top 150 for the first time on October 22, being ranked world No. 149. He closed out the season on a high note, reaching the final of the Liuzhou challenger and winning the Shenzhen challenger, to finish the season with a then career-high ranking of world No. 132.


title: Miomir Kecmanović

text: He earned his first ATP victory by defeating world No. 56 Leonardo Mayer at the Brisbane International. He played in the BNP Paribas Open as a lucky loser. He defeated 30th seed Laslo Đere on his way to the quarterfinals, before losing to in straight sets to Milos Raonic. This result meant that Kecmanović was ranked in the top 100 for the first time. In Miami, he beat former top-10 player Ernests Gulbis in the first round before losing to Frances Tiafoe in two tiebreak sets.


title: Miomir Kecmanović

text: At the French Open, Kecmanović played in the main draw, beating Denis Kudla in five sets before losing to David Goffin. This was his first grand slam win. At the Antalya Open, he reached his first ATP final, losing to Lorenzo Sonego in the final. His semi final against 3rd seed Jordan Thompson was notable for featuring no breaks of serve, with Kecmanović saving all three break points on his serve.


title: Miomir Kecmanović

text: Kecmanović won his first Wimbledon match at The Championships 2019, beating Roberto Carballés Baena in four sets, before retiring against Benoît Paire two sets to love down. In Atlanta, he beat Jack Sock and 8th seed Ugo Humbert both in straight sets, before losing in the quarter-finals to eventual finalist and 2nd seed Taylor Fritz. In the Citi Open, he beat Alexei Popyrin and Pierre-Hugues Herbert before losing to Norbert Gombos. Having missed the Roger's Cup Masters Tournament, Kecmanović's breakthrough came at the Western and Southern Open. In the qualifying rounds, he beat Antoine Hoang and Feliciano López in straight sets. In the first round, he beat fellow 19 year old Félix Auger-Aliassime in straight sets. He then gained his first win over a top ten player by beating 7th seed Alexander Zverev in three sets. This victory ensured that Kecmanović would break into the top 50 for the first time. He then lost in straight sets to Roberto Bautista Agut.


title: Miomir Kecmanović

text: Kecmanović started off the new decade by participating in the ATP 250 Qatar Open. He defeated Australian Jordan Thompson before defeating third seed Jo-Wilfried Tsonga in the round of sixteen. He won his first ATP title at the Austrian Open Kitzbühel in September.


title: Miomir Kecmanović

text: After reaching the second round at the Australian Open, losing to Adrian Mannarino, and following a semifinal run at the 2021 Argentina Open, Kecmanović achieved his best singles ranking of world No. 38 on 8 March 2021. During the Latin American Swing, he hired former World No. 3 player David Nalbandian as his coach for a trial period.


title: Miomir Kecmanović

text: Kecmanović was initially set to play Novak Djokovic in the Australian Open. Due to Djokovic’s visa issues and his COVID-19 vaccination status, that ultimately led to his deportation, Kecmanović instead faced Salvatore Caruso who was promoted to Djokovic's original position as a lucky loser. Kecmanovic defeated Caruso in straight sets, and advanced to the second round.


title: Miomir Kecmanović

text: Next he defeated Tommy Paul in straight sets and Lorenzo Sonego to make his first fourth round at a Major, which is his best result at a Grand Slam. He lost to 17th seed Gaël Monfils in straight sets in the fourth round. At the 2022 Rio Open he reached the quarterfinals as a qualifier defeating sixth seed Lorenzo Sonego. He lost to Francisco Cerundolo in a second consecutive match, the first loss coming at the previous tournament, the 2022 Argentina Open.


title: Miomir Kecmanović

text: At the BNP Paribas Open, Kecmanović reached his 2nd career Masters 1000 quarterfinal. He defeated Liam Broady, 24th seed Marin Čilić, Botic van de Zandschulp, and 6th seed Matteo Berrettini, earning the second Top 10 win of his career. He lost in the quarterfinals in three sets to eventual champion Taylor Fritz.


title: Miomir Kecmanović

text: The following week at the Miami Open, Kecmanović reached his 2nd consecutive Masters 1000 quarterfinal and 3rd overall. He defeated Jack Sock, 7th seed and 9th ranked Félix Auger-Aliassime for his third Top 10 win, Sebastian Korda, and 11th seed Taylor Fritz in a rematch of the previous week's Indian Wells quarterfinal. He lost to eventual champion Carlos Alcaraz in the quarterfinal in a final set tie-breaker. Due to this result, Kecmanović tied his career high ranking of World No. 38. He made his debut in the top 30 on 13 June 2022 following a third round showing for the first time in his career at the 2022 French Open.


title: Miomir Kecmanović

text: At Wimbledon, he beat Alejandro Tabilo and John Millman in the first two rounds before losing to the number 1 seed and eventual champion Novak Djokovic in the third round.


title: Miomir Kecmanović

text: Born in Belgrade, to Dragutin Kecmanović and Maja Pavlov, both doctors, specialists in general and abdominal surgery. Miomir began playing tennis at the age of 6 with his maternal grandfather, Jovan Pavlov, who was a General in Yugoslav People's Army. His paternal grandfather was Prof. Miomir Kecmanovic, after whom Miomir was named, who played a crucial role in suppressing the 1972 Yugoslav smallpox outbreak. Growing up, his tennis idols were Roger Federer and Novak Djokovic. At age 13, he moved to Florida with his aunt, Tanja Pavlov, a psychologist, to train at IMG Academy. His aunt also acts as his manager.


title: Miomir Kecmanović

text: "Kecmanović's record against those who have been ranked in the top 10, with active players in boldface:"


title: Santosh Yadav

text: Santosh Yadav (born 10 October 1967) is an Indian mountaineer. She is the first woman in the world to climb Mount Everest twice and the first woman to successfully climb Mount Everest from Kangshung Face. She climbed the peak first in May 1992 and then again in May 1993 with an Indo-Nepalese Team.


title: Santosh Yadav

text: During her Everest mission in 1992, she saved the life of a climber, Mohan Singh, by sharing oxygen with him. She also tried to help a mountaineer who lay dying at the South Col but was unsuccessful in saving him.


title: Santosh Yadav

text: She was born in Joniyawas village in Rewari district of Haryana state, India as the sixth child in a family of five boys. She earlier attended a local village school and then moved to Delhi and got enrolled in a school there. She attended Maharani College in Jaipur, where she was able to see mountaineers climbing Aravalli Range from her room. She was inspired by this to join Uttarkashi's Nehru Institute of Mountaineering while successfully continuing her studies for the Indian Administrative Service (IAS) exams in a hostel provided by the Amity University at Noida.


title: Santosh Yadav

text: In 1992, Yadav scaled Mount Everest , when she was barely 25, becoming the youngest woman in the world to achieve this feat, a record which was broken by 13-year-old Malavath Purna, in 2013. Within twelve months, she became a member of an Indo-Nepalese Women's expedition and scaled Everest the second time, thus setting the record as the first woman to have scaled Everest twice. She also remained as an officer in the Indo-Tibetan Border Police. She was a part of the nine-nation international climbing camp-cum-expedition to Nun Kun in 1989. Also, her being a fervent environmentalist, she collected 500 kgs of dumped wastes from the Himalayas.


title: Taenia saginata

text: Taenia saginata (synonym Taeniarhynchus saginatus), commonly known as the beef tapeworm, is a zoonotic tapeworm belonging to the order Cyclophyllidea and genus "Taenia". It is an intestinal parasite in humans causing taeniasis (a type of helminthiasis) and cysticercosis in cattle. Cattle are the intermediate hosts, where larval development occurs, while humans are definitive hosts harbouring the adult worms. It is found globally and most prevalently where cattle are raised and beef is consumed. It is relatively common in Africa, Europe, Southeast Asia, South Asia, and Latin America. Humans are generally infected as a result of eating raw or undercooked beef which contains the infective larvae, called cysticerci. As hermaphrodites, each body segment called proglottid has complete sets of both male and female reproductive systems. Thus, reproduction is by self-fertilisation. From humans, embryonated eggs, called oncospheres, are released with faeces and are transmitted to cattle through contaminated fodder. Oncospheres develop inside muscle, liver, and lungs of cattle into infective cysticerci.


title: Taenia saginata

text: "T. saginata" has a strong resemblance to the other human tapeworms, such as "Taenia asiatica" and "Taenia solium", in structure and biology, except for few details. It is typically larger and longer, with more proglottids, more testes, and higher branching of the uteri. It also lacks an armed scolex unlike other "Taenia". Like the other tapeworms, it causes taeniasis inside the human intestine, but does not cause cysticercosis. Its infection is relatively harmless and clinically asymptomatic.


title: Taenia saginata

text: "T. saginata" is the largest of species in the genus "Taenia". An adult worm is normally 4 to 10 m in length, but can become very large; specimens over 22 m long are reported. Typical of cestodes, its body is flattened dorsoventrally and heavily segmented. It is entirely covered by a tegument. The body is white in colour and consists of three portions: scolex, neck, and strobila. The scolex has four suckers, but they have no hooks. Lack of hooks and a rostellum is an identifying feature from other "Taenia" species. The rest of the body proper, the strobila, is basically a chain of numerous body segments called proglottids. The neck is the shortest part of the body, and consists of immature proglottids. The midstrobila is made of mature proglottids that eventually lead to the gravid proglottids, which are at the posterior end. An individual can have as many as 1000 to 2000 proglottids.


title: Taenia saginata

text: "T. saginata" does not have a digestive system, mouth, anus, or digestive tract. It derives nutrients from the host through its tegument, as the tegument is completely covered with absorptive hair-like microtriches. It is also an acoelomate, having no body cavity. The inside of each mature proglottid is filled with muscular layers and complete male and female reproductive systems, including the tubular unbranched uterus, ovary, genital pore, testes, and vitelline gland. In the gravid proglottid, the uterus contains up to 15 side branches filled with eggs.


title: Taenia saginata

text: Cattle acquire the embryonated eggs, the oncospheres, when they eat contaminated food. Oncospheres enter the duodenum, the anterior portion of the small intestine, and hatch there under the influence of gastric juices. The embryonic membranes are removed, liberating free hexacanth ("six-hooked") larvae. With their hooks, they attach to the intestinal wall and penetrate the intestinal mucosa into the blood vessels. The larvae can move to all parts of the body by the general circulatory system, and finally settle in skeletal muscles within 70 days. Inside the tissue, they cast off their hooks and instead develop a protective cuticular shell, called the cyst. Thus, they become fluid-filled cysticerci. Cysterci can also form in lungs and liver. The inner membrane of the cysticercus soon develops numerous protoscolices (small scolices) that are invertedly attached to the inner surface. The cysticercus of "T. saginata" is specifically named "cysticercus bovis" to differentiate from that of "T. solium", "cysticercus cellulosae".


title: Taenia saginata

text: Humans contract infective cysticerci by eating raw or undercooked meat. Once reaching the jejunum, the inverted scolex becomes evaginated to the exterior under stimuli from the digestive enzymes of the host. Using the scolex, it attaches to the intestinal wall. The larva mature into adults about 5 to 12 weeks later. Adult worms can live about 25 years in the host. Usually, only a single worm is present at time, but multiple worms are also reported. In each mature proglottid, self-fertilisation produces zygotes, which divide and differentiate into embryonated eggs called oncospheres. With thousands of oncospheres, the oldest gravid proglottids detach. Unlike in other "Taenia", gravid proglottids are shed individually. In some cases, the proglottid ruptures inside the intestine, and the eggs are released. The free proglottids and liberated eggs are removed by peristalsis into the environment. On the ground, the proglottids are motile and shed eggs as they move. These oncospheres in an external environment can remain viable for several days to weeks in sewage, rivers, and pastures.


title: Taenia saginata

text: The disease is relatively common in Africa, some parts of Eastern Europe, the Philippines, and Latin America. This parasite is found anywhere where beef is eaten, including countries such as the United States, with strict federal sanitation policies. In the US, the incidence of infection is low, but 25% of cattle sold are still infected. The total global infection is estimated to be between 40 and 60 million. It is most prevalent in Sub-Saharan Africa and the Middle East.


title: Taenia saginata

text: "T. saginata" infection is usually asymptomatic, but heavy infection often results in weight loss, dizziness, abdominal pain, diarrhea, headaches, nausea, constipation, chronic indigestion, and loss of appetite. Intestinal obstruction in humans can be alleviated by surgery. The tapeworm can also expel antigens that can cause an allergic reaction in the individual. It is also a rare cause of ileus, pancreatitis, cholecystitis, and cholangitis. "Taenia saginata" has been reported as a cause of gallbladder perforation if left untreated in some cases. "Taenia saginata" adult worms can live in the host for up to 25 years and most infections will last 2 to 3 years without treatment.


title: Taenia saginata

text: The "Taenia saginata" remains asymptomatic due to the fact the organism does not present cysticerci in humans. Therefore, there is no presence of cysticercosis in humans either. Typically, cysticercosis is a parasitical tissue infection which infect the brain and muscle tissues. However the "Taenia saginata" can cause taeniasis, which is an infection. Taeniasis causes weight loss, pain and blockages in the intestines which can potentially become life-threatening.


title: Taenia saginata

text: The basic diagnosis is done from a stool sample. Feces are examined to find parasite eggs. The eggs look like other eggs from the family Taeniidae, so it is only possible to identify the eggs to the family, not to the species level. Since it is difficult to diagnose using eggs alone, looking at the scolex or the gravid proglottids can help identify it as "Taenia saginata". Proglottids sometimes trickle down the thighs of infected humans and are visible with unaided eye, so can aid with identification. Observation of scolex help distinguish between "T. saginata", "T. solium" and "T. asiatica". When the uterus is injected with India ink, its branches become visible. Counting the uterine branches enables some identification ("T. saginata" uteri have 12 or more branches on each side, while other species such as "T. solium" only have five to 10).


title: Taenia saginata

text: Differentiation of the species of "Taenia", such as "T. solium" and "T. asiatica", is notoriously difficult because of their close morphological resemblance, and their eggs are more or less identical. Identification often requires histological observation of the uterine branches and PCR detection of ribosomal 5.8S gene. The uteri of "T. saginata" stem out from the center to form 12 to 20 branches, but in contrast to its closely related "Taenia" species, the branches are much less in number and comparatively thicker; in addition, the ovaries are bilobed and testes are twice as many.


title: Taenia saginata

text: Eosinophilia and elevated IgE levels are chief hematological findings. Also Ziehl–Neelsen stain can be used to differentiate between mature "T. saginata" and "T. solium", in most cases "T. saginata" will stain while "T. solium" will not, but the method is not strictly reliable.


title: Taenia saginata

text: Taenaisis is easily treated with praziquantel (5–10 mg/kg, single-administration) or niclosamide (adults and children over 6 years: 2 g, single-administration after a light breakfast, followed after 2 hours by a laxative; children aged 2–6 years: 1 g; children under 2 years: 500 mg). Albendazole is also highly effective for treatment of cattle infection. During the 1940s, the preferred treatment was oleoresin of aspidium, which would be introduced into the duodenum via a Rehfuss tube.


title: Taenia saginata

text: Adequate cooking at for 5 minutes of beef viscera destroys cysticerci. Refrigeration, freezing at for 9 days or long periods of salting is lethal to cysticerci. Inspection of beef and proper disposal of human excreta are also important measures.


title: Greatest Hits (Tupac Shakur album)

text: Greatest Hits is a posthumous double-disc greatest hits album by American rapper 2Pac, released by Amaru Entertainment, Death Row Records, and Interscope Records on November 24, 1998.


title: Greatest Hits (Tupac Shakur album)

text: The album's non-chronological sequence focuses on the highlights of 2Pac's career. 21 of his tracks are accompanied by four previously unreleased songs: "God Bless the Dead", "Unconditional Love", "Troublesome '96", and "Changes". Some tracks have alternate mixes, while the original mix of "California Love" makes its first proper album appearance after initially only being available as a single.


title: Greatest Hits (Tupac Shakur album)

text: "Changes" earned 2Pac the first and only posthumous Grammy Award nomination for Best Rap Solo Performance. This is one of two 2Pac releases—and one of only nine hip hop albums—to have been certified Diamond in the United States.


title: Greatest Hits (Tupac Shakur album)

text: "Greatest Hits" debuted at number five on the US "Billboard" 200 chart, selling 268,000 copies in its first week. In January 1999, the album reached its peak at number three on the chart. It has spent 433 weeks on the "Billboard 200". On October 16, 2000, it was certified 9× platinum. Nearly 11 years later, in June 2011, it was certified by the RIAA for shipments of over 10 million, the late rapper's first RIAA Diamond award. With 5.33 million units sold which is 10.66 million in RIAA sales, it remains the best-selling rap greatest hits compilation of all time and the twentieth best-selling rap album since Nielsen Soundscan began tracking record sales in 1991.


title: Greatest Hits (Tupac Shakur album)

text: Tupac Shakur's virtual appearance at the annual Coachella Festival on April 15, 2012, spurred a re-entry for the album on the "Billboard" 200 chart; it jumped in at No. 129 with 4,000 copies sold according to Nielsen SoundScan (a gain of 571% over the previous week).


title: Greatest Hits (Tupac Shakur album)

text: The album was certified Platinum by the BPI on 16 August 2002, making it 2Pac's highest selling album in the UK.


title: Tipping points in the climate system

text: In climate science, a tipping point is a critical threshold that, when crossed, leads to large and often irreversible changes in the climate system. If tipping points are crossed, they are likely to have severe impacts on human society. Tipping behaviour is found across the climate system, in ecosystems, ice sheets, and the circulation of the ocean and atmosphere.


title: Tipping points in the climate system

text: Tipping points are often, but not necessarily, abrupt. For example, with average global warming somewhere between 0.8 and 3 °C, the Greenland ice sheet passes a tipping point and is doomed, but the melt would take place over millennia.


title: Tipping points in the climate system

text: Tipping points are possible at today's global warming of just over 1 °C above preindustrial times, and highly probable above 2 °C of global warming. The geological record shows many abrupt changes that suggest tipping points may have been crossed in ancient times. It is possible that some tipping points are close to being crossed or have already been crossed, like those of the West Antarctic and Greenland ice sheets, the Amazon rainforest and warm-water coral reefs. A danger is that if the tipping point in one system is crossed, this could cause a cascade of other tipping points, leading to severe impacts.


title: Tipping points in the climate system

text: The sixth report from the United Nations Intergovernmental Panel on Climate Change (IPCC), released in 2021, defines a tipping point as a "critical threshold beyond which a system reorganizes, often abruptly and/or irreversibly". It can be brought about by a small disturbance causing a disproportionately large change in the system. One set of definitions of "tipping points" also requires self-reinforcing feedbacks, which could lead to changes in the climate system irreversible on a human timescale. For any particular climate component, the shift from one state to a new stable state may take many decades or centuries. In ecosystems and in social systems, a tipping point can trigger a "regime shift", a major systems reorganisation into a new stable state.


title: Tipping points in the climate system

text: The 2019 IPCC Special Report on the Ocean and Cryosphere in a Changing Climate defines a tipping point as: "A level of change in system properties beyond which a system reorganises, often in a non-linear manner, and does not return to the initial state even if the drivers of the change are abated. For the climate system, the term refers to a critical threshold at which global or regional climate changes from one stable state to another stable state.".


title: Tipping points in the climate system

text: The geological record shows that there have been abrupt changes in the climate system that indicate ancient tipping points. For instance, the Dansgaard–Oeschger events during the last ice age were periods of abrupt warming (within decades) in Greenland and Europe, that may have involved the abrupt changes in major ocean currents. During the deglaciation in the early Holocene, sea level rise was not smooth, but rose abruptly during meltwater pulses. The monsoon in North Africa saw abrupt changes on decadal timescales during the African humid period. This period, spanning from 15,000 to 5,000 years ago, also ended suddenly in a drier state.


title: Tipping points in the climate system

text: Scientists have identified many elements in the climate system which may have tipping points. in the early 2000s the IPCC began considering the possibility of tipping points. At that time the IPCC concluded they would only be likely in the event of global warming of 4 °C or more above preindustrial times. As of 2021 tipping points are considered to have significant probability at today's warming level of just over 1 °C, with high probability above 2 °C of global warming, and it is possible that some tipping points are close to being crossed or have already been crossed, like those of the ice sheets in West Antarctic and Greenland, warm-water coral reefs, and the Amazon rainforest. As of September 2022, nine core tipping elements and seven regional impact tipping elements were identified. Out of those, one regional and three core climate elements are estimated to likely pass a tipping point if global warming reaches 1.5 °C, namely the Greenland ice sheet collapse, the West Antarctic ice sheet collapse, tropical coral reef die off, and the boreal permafrost abrupt thaw. Two further tipping points are forecast as likely if warming continues to approach 2 °C : Barents sea ice abrupt loss, and the Labrador sea subpolar gyre collapse.


title: Tipping points in the climate system

text: The Greenland ice sheet is the second largest ice sheet in the world, and is three times the size of the American state of Texas. It holds enough water, that if completely melted, could raise sea levels globally by 7.2 metres. Due to global warming, the ice sheet is melting at an accelerating rate, adding almost 1 mm to global sea levels every year. Around half of the ice loss occurs via surface melting, and the remainder occurs at the base of the ice sheet where the ice sheet touches the sea, by calving (breaking off) icebergs from its margins.


title: Tipping points in the climate system

text: The Greenland ice sheet has a tipping point because of the melt-elevation feedback. Surface melting reduces the height of the ice sheet. As air at a lower altitude is warmer, the ice sheet is then exposed to warmer temperatures, accelerating the melt. A 2021 analysis of sub-glacial sediment at the bottom of a 1.4 km Greenland ice core finds that the Greenland ice sheet melted away at least once during the last million years, and therefore strongly suggests that its tipping point is below the 2.5 °C maximum positive temperature excursion over that period. There is some evidence that the Greenland ice sheet is losing stability, and getting close to a tipping point.


title: Tipping points in the climate system

text: The West Antarctic Ice Sheet (WAIS) is a large ice sheet in Antarctica; in places more than 4 kilometres thick. It sits on bedrock mostly below sea level. As such, it is in contact with the heat from the ocean which makes it vulnerable to fast and irreversible ice loss. A tipping point could be reached if thinning or collapse of the WAIS's ice shelves triggers a feedback loop that leads to rapid and irreversible loss of its ice into the ocean. If completely melted, the ice sheet would contribute around 3.3 metres of sea level rise.


title: Tipping points in the climate system

text: Ice loss from the WAIS is accelerating. The paleo record suggests that during the past few hundred thousand years, the WAIS largely disappeared in response to similar levels of warming and emission scenarios projected for the next few centuries.


title: Tipping points in the climate system

text: Like with the other ice sheets, there is a counteracting negative feedback - greater warming also intensifies the effects of climate change on the water cycle, which result in an increased precipitation over the ice sheet in the form of snow during the winter, which would freeze on the surface, and this increase in the surface mass balance (SMB) counteracts some fraction of the ice loss. In the IPCC Fifth Assessment Report, it was suggested that this effect could potentially overpower increased ice loss under the higher levels of warming and result in small net ice gain, but by the time of the IPCC Sixth Assessment Report, improved modelling had proven that the glacier breakup would consistently accelerate at a faster rate.


title: Tipping points in the climate system

text: East Antarctic ice sheet is the largest and thickest ice sheet on Earth, with the maximum thickness of 4,800 m. A complete disintegration would raise the global sea levels by 53.3 m, but this may not occur until global warming of 10 degrees Celsius, while the loss of two-thirds of its volume may require at least 6 degrees of warming to trigger. Its melt would also occur over a longer timescale than the loss of any other ice on the planet, taking no less than 10,000 years to finish. However, the subglacial basin portions of the East Antarctic ice sheet may be vulnerable to tipping at lower levels of warming. The Wilkes Basin is of particular concern, as it holds enough ice to raise sea levels by about 3 to 4 metres.


title: Tipping points in the climate system

text: The Amazon rainforest is the largest tropical rainforest in the world. It is twice as big as India and spans nine countries in South America. It produces around half of its own rainfall by recycling moisture through evaporation and transpiration as air moves across the forest. When forest is lost via climate change (droughts and fires) or deforestation, there will be less rain and more trees will die. Eventually, large parts of the rainforest may die off and transform into a dry savanna landscape. In 2022, a study reported that the rainforest has been losing resilience since the early 2000s. Resiliency is measured by recovery-time from short-term perturbations. This delayed return to equilibrium of the rainforest is termed "critical slowing down". The observed loss of resilience reinforces the theory that the rainforest is approaching a critical transition.


title: Tipping points in the climate system

text: Perennially frozen ground, or permafrost, covers large fractions of land – mainly in Siberia, Alaska, northern Canada and the Tibetan plateau – and can be up to a kilometre thick. Subsea permafrost up to 100 metres thick also occurs on the sea floor under part of the Arctic Ocean. This frozen ground holds vast amounts of carbon from plants and animals that died and decomposed over thousands of years. Scientists believe there is nearly twice as much carbon in permafrost than is present in Earth's atmosphere. As the climate warms and the permafrost begins to thaw, carbon dioxide and methane are released into the atmosphere. With higher temperatures, microbes become active and decompose the biological material in the permafrost. This could happen rapidly, or over longer timespans, and the loss would be irreversible. Because and methane are both greenhouse gases, they act as a self-reinforcing feedback on permafrost melt.


title: Tipping points in the climate system

text: The Atlantic Meridional Overturning Circulation (AMOC), also known as the Gulf Stream System, is a large system of ocean currents. It is driven by differences in the density of water; colder and more salty water is heavier than warmer fresh water. The AMOC acts as a conveyor belt, sending warm surface water from the tropics north, and carrying cold fresh water back south. As warm water flows northwards, some evaporates which increases salinity. It also cools when it is exposed to cooler air. Cold, salty water is more dense and slowly begins to sink. Several kilometres below the surface, cold, dense water begins to move south. Increased rainfall and the melting of ice due to global warming dilutes the salty surface water, and warming further decreases its density. The lighter water is less able to sink, slowing down the circulation.


title: Tipping points in the climate system

text: Theory, simplified models, and reconstructions of abrupt changes in the past suggest the AMOC has a tipping point. If freshwater input from melting glaciers reaches a certain threshold, it could collapse into a state of reduced flow. Even after melting stops, the AMOC may not return to its current state. It is unlikely that the AMOC will tip in the 21st century, but it may do so before 2300 if greenhouse gas emissions are very high. A weakening of 24% to 39% is expected depending on greenhouse emissions, even without tipping behaviour. If the AMOC does shut down, a new stable state could emerge that lasts for thousands of years, possibly triggering other tipping points.


title: Tipping points in the climate system

text: In 2021, a study which used a "primitive" finite-difference ocean model estimated that AMOC collapse could be invoked by a sufficiently fast increase in ice melt even if it never reached the common thresholds for tipping obtained from slower change. Thus, it implied that the AMOC collapse is more likely than what is usually estimated by the complex and large-scale climate models. Another 2021 study found early-warning signals in a set of AMOC indices, suggesting that the AMOC may be close to tipping. However, it was contradicted by another study published in the same journal the following year, which found a "largely stable" AMOC which had so far not been affected by climate change beyond its own natural variability. Two more studies published in 2022 have also suggested that the modelling approaches commonly used to evaluate AMOC appear to overestimate the risk of its collapse.


title: Tipping points in the climate system

text: Arctic sea ice was once identified as a potential tipping element. The loss of sunlight-reflecting sea ice during summer exposes the (dark) ocean, which would warm. Arctic sea ice cover is likely to melt entirely under even relatively low levels of warming, and it was hypothesized that this could eventually transfer enough heat to the ocean to prevent sea ice recovery even if the global warming is reversed. Modelling now shows that this heat transfer during the Arctic summer does not overcome the cooling and the formation of new ice during the Arctic winter. As such, the loss of Arctic ice during the summer is not a tipping point for as long as the Arctic winter remains cool enough to enable the formation of new Arctic sea ice. However, if the higher levels of warming prevent the formation of new Arctic ice even during winter, then this change may become irreversible. Consequently, Arctic Winter Sea Ice is included as a potential tipping point in a 2022 assessment.


title: Tipping points in the climate system

text: Additionally, the same assessment argued that while the rest of the ice in the Arctic Ocean may recover from a total summertime loss during the winter, ice cover in the Barents Sea may not reform during the winter even below 2 degrees of warming. This is because the Barents Sea is already the fastest-warming part of the Arctic: in 2021-2022 it was found that while the warming within the Arctic Circle has already been nearly four times faster than the global average since 1979, Barents Sea warmed up to seven times faster than the global average. This tipping point matters because of the decade-long history of research into the connections between the state of Barents-Kara Sea ice and the weather patterns elsewhere in Eurasia.


title: Tipping points in the climate system

text: Around 500 million people around the world depend on coral reefs for food, income, tourism and coastal protection. Since the 1980s, this is being threatened by the increase in sea surface temperatures which is triggering mass bleaching of coral, especially in sub-tropical regions. A sustained ocean temperature spike of 1 °C above average is enough to cause bleaching. Under heat stress, corals expel the small colourful algae which live in their tissues, which causes them to turn white. The algae, known as zooxanthellae, have a symbiotic relationship with coral such that without them, the corals slowly die. After these zooxanthellae have disappeared, the corals are vulnerable to a transition towards a seaweed-dominated ecosystem, making it very difficult to shift back to a coral-dominated ecosystem. The IPCC estimates that by the time temperatures have risen to 1.5 °C above pre-industrial times, between 70% and 90% of coral reefs that exist today will disappear; and that if the world warms by 2 °C, they will become extremely rare.


title: Tipping points in the climate system

text: Mountain glaciers are the largest repository of land-bound ice after the Greenland and the Antarctica ice sheets, and they are also undergoing melting as the result of climate change. A glacier tipping point is when it enters a disequilibrium state with the climate and will melt away unless the temperatures go down. Examples include glaciers of the North Cascade Range, where even in 2005 67% of the glaciers observed were in disequilibrium and will not survive the continuation of the present climate, or the French Alps, where The Argentière and Mer de Glace glaciers are expected to disappear completely by end of the 21st century if current climate trends persist.


title: Tipping points in the climate system

text: The absolute largest amount of glacier ice is located in the Hindu Kush Himalaya region, which is colloquially known as the Earth's "Third Pole" as the result. It is believed that one third of that ice will be lost by 2100 even if the warming is limited to 1.5 °C, while the "intermediate" and "severe" climate change scenarios (RCP 4.5 and 8.5) are likely to lead to the losses of 50% and >67% of the region's glaciers over the same timeframe. Glacier melt is projected to accelerate regional river flows until the amount of meltwater peaks around 2060, going into an irreversible decline afterwards. Since regional precipitation will continue to increase even as the glacier meltwater contribution declines, annual river flows are only expected to diminish in the western basins where contribution from the monsoon is low: however, irrigation and hydropower generation would still have to adjust to greater interannual variability and lower pre-monsoon flows in all of the region's rivers.


title: Tipping points in the climate system

text: During the last quarter of the twentieth century, the zone of latitude occupied by taiga experienced some of the greatest temperature increases on Earth. Winter temperatures have increased more than summer temperatures. In summer, the daily low temperature has increased more than the daily high temperature. It has been hypothesized that the boreal environments have only a few states which are stable in the long term - a treeless tundra/steppe, a forest with >75% tree cover and an open woodland with ~20% and ~45% tree cover. Thus, continued climate change would be able to force at least some of the presently existing taiga forests into one of the two woodland states or even into a treeless steppe - but it could also shift tundra areas into woodland or forest states as they warm and become more suitable for tree growth.


title: Tipping points in the climate system

text: These trends were first detected in the Canadian boreal forests in the early 2010s, and summer warming had also been shown to increase water stress and reduce tree growth in dry areas of the southern boreal forest in central Alaska and portions of far eastern Russia. In Siberia, the taiga is converting from predominantly needle-shedding larch trees to evergreen conifers in response to a warming climate. Subsequent research in Canada found that even in the forests where biomass trends did not change, there was a substantial shift towards the deciduous broad-leaved trees with higher drought tolerance over the past 65 years, and a Landsat analysis of 100,000 undisturbed sites found that the areas with low tree cover became greener in response to warming, but tree mortality (browning) became the dominant response as the proportion of existing tree cover increased. A 2018 study of the seven tree species dominant in the Eastern Canadian forests found that while 2 °C warming alone increases their growth by around 13% on average, water availability is much more important than temperature and further warming of up to 4 °C would result in substantial declines unless matched by increases in precipitation.


title: Tipping points in the climate system

text: A 2021 paper had confirmed that the boreal forests are much more strongly affected by climate change than the other forest types in Canada and projected that most of the eastern Canadian boreal forests would reach a tipping point around 2080 under the RCP 8.5 scenario, which represents the largest potential increase in anthropogenic emissions. Another 2021 study projected that under the "moderate" SSP2-4.5 scenario, boreal forests would experience a 15% worldwide increase in biomass by the end of the century, but this would be more than offset by the 41% biomass decline in the tropics. In 2022, the results of a 5-year warming experiment in North America had shown that the juveniles of tree species which currently dominate the southern margins of the boreal forests fare the worst in response to even 1.5°C or +3.1 °C of warming and the associated reductions in precipitation. While the temperate species which would benefit from such conditions are also present in the southern boreal forests, they are both rare and have slower growth rates.


title: Tipping points in the climate system

text: The possibility that the El Niño–Southern Oscillation (ENSO) is a tipping element had attracted attention in the past. Normally strong winds blow west across the South Pacific Ocean from South America to Australia. Every two to seven years, the winds weaken due to pressure changes and the air and water in the middle of the Pacific warms up, causing changes in wind movement patterns around the globe. This known as El Niño and typically leads to droughts in India, Indonesia and Brazil, and increased flooding in Peru. In 2015/2016, this caused food shortages affecting over 60 million people. El Niño-induced droughts may increase the likelihood of forest fires in the Amazon. The threshold for tipping was estimated to be between 3.5 and 7 °C of global warming in 2016. After tipping, the system would be in a more permanent El Niño state, rather than oscillating between different states. This has happened in Earth's past, in the Pliocene, but the layout of the ocean was significantly different from now. So far, there is no definitive evidence indicating changes in ENSO behaviour, and the IPCC Sixth Assessment Report concluded that it is "virtually certain that the ENSO will remain the dominant mode of interannual variability in a warmer world." Consequently, the 2022 assessment no longer includes it in the list of likely tipping elements.


title: Tipping points in the climate system

text: The Indian summer monsoon is another part of the climate system which was considered suspectible to irreversible collapse in the earlier research. However, more recent research has demonstrated that warming tends to strengthen the Indian monsoon, and it is projected to strengthen in the future.


title: Tipping points in the climate system

text: Methane hydrate deposits in the Arctic were once thought to be vulnerable to a rapid dissociation which would have a large impact on global temperatures, in a dramatic scenario known as a clathrate gun hypothesis. Later research found that it takes millennia for methane hydrates to respond to warming, while methane emissions from the seafloor rarely transfer from the water column into the atmosphere. IPCC Sixth Assessment Report states "It is very unlikely that gas clathrates (mostly methane) in deeper terrestrial permafrost and subsea clathrates will lead to a detectable departure from the emissions trajectory during this century".


title: Tipping points in the climate system

text: Tipping point behaviour in the climate can be described in mathematical terms. Three types of tipping points have been identified—bifurcation, noise-induced and rate-dependent.


title: Tipping points in the climate system

text: Bifurcation-induced tipping happens when a particular parameter in the climate (for instance a change in environmental conditions or forcing), passes a critical level – at which point a bifurcation takes place – and what was a stable state loses its stability or simply disappears. The Atlantic Meridional Overturning Circulation (AMOC) is an example of a tipping element that can show bifurcation-induced tipping. Slow changes to the bifurcation parameters in this system – the salinity and temperature of the water – may push the circulation towards collapse.


title: Tipping points in the climate system

text: Many types of bifurcations show hysteresis, which is the dependence of the state of a system on its history. For instance, depending on how warm it was in the past, there can be differing amounts of ice on the poles at the same concentration of greenhouse gases or temperature.


title: Tipping points in the climate system

text: For tipping points that occur because of a bifurcation, it may be possible to detect whether a system is getting closer to a tipping point, as it becomes less resilient to perturbations on approach of the tipping threshold. These systems display critical slowing down, with an increased memory (rising autocorrelation) and variance. Depending on the nature of the tipping system, there may be other types of early warning signals. Abrupt change is not an early warning signal (EWS) for tipping points, as abrupt change can also occur if the changes are reversible to the control parameter.


title: Tipping points in the climate system

text: These EWSs are often developed and tested using time series from the paleo record, like sediments, ice caps, and tree rings, where past examples of tipping can be observed. It is not always possible to say whether increased variance and autocorrelation is a precursor to tipping, or caused by internal variability, for instance in the case of the collapse of the AMOC. Quality limitations of paleodata further complicate the development of EWSs. They have been developed for detecting tipping due to drought in forests in California, and melting of the Pine Island Glacier in West Antarctica, among other systems. Using early warning signals (increased autocorrelation and variance of the melt rate time series), it has been suggested that the Greenland ice sheet is currently losing resilience, consistent with modelled early warning signals of the ice sheet.


title: Tipping points in the climate system

text: Human-induced changes in the climate system may be too fast for early warning signals to become evident, especially in systems with inertia.


title: Tipping points in the climate system

text: Noise-induced tipping is the transition from one state to another due to random fluctuations or internal variability of the system. Noise-induced transitions do not show any of the early warning signals which occur with bifurcations. This means they are unpredictable because the underlying potential does not change. Because they are unpredictable, such occurrences are often described as a "one-in-x-year" event. An example is the Dansgaard–Oeschger events during the last ice age, with 25 occurrences of sudden climate fluctuations over a 500 year period.