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101-444: Megafloods are paleofloods (past floods) that involved rates of water flow larger than those in the historical record. They are studied through the sedimentary deposits and the erosional and constructional landforms that individual megafloods have created. Floods that are known to us through historical descriptions are mostly related to meteorological events, such as heavy rains, rapid melting of snowpacks, or combination of these. In

202-783: A change in assemblages from those that inhabit marine environments to those that live in much less saline conditions at about 11.4 to 11.2 ka BP (Fig. 4). In the specific core sample (core Melo-5, location noted in Fig. 3) analysis shown in Fig. 4, there is a change in assemblages from almost 100% E. clavata (which inhabits marine environments) to >50% E. albiumbilicatum (which prefers less saline conditions)—both species of Elphidium . This transition seems to be probable, as it has been corroborated by multiple studies. The overall decrease in salinity has been estimated to be from 25 psu to less than 15 psu ( practical salinity units ). The decrease in salinity starting at Melo-1 and moving to Melo-5 indicates

303-590: A change in thermohaline circulation and climate change. Lake Agassiz did not exist long before the Younger Dryas cold period, so changes in the thermohaline circulation and climate before then would have probably been caused by re-routing of other North American drainage basins , possibly coupled with an influx of icebergs. However, the Younger Dryas cold period has been linked to flood water diversion from Lake Agassiz. Water that normally flowed through

404-537: A decline for the academy as he cut funding for academic institutions and prohibited Russians from attending Western influenced institutions. In 1803, Alexander I reverted to reforms from Catherine the Great's era and gave the academy self-administration power in a new charter. The new charter came with a name change to the Imperial Academy of Sciences. Following Leibniz's instructions, Peter reached out to

505-582: A dedicated Russian Space Science Internet (RSSI). Started with just three members, The RSSI now has 3,100 members, including 57 from the largest research institutions. Russian universities and technical institutes are not under the supervision of the RAS (they are subordinated to the Ministry of Education of Russian Federation), but a number of leading universities, such as Moscow State University , St. Petersburg State University , Novosibirsk State University , and

606-464: A depressed fresh-water lake in a single catastrophe that has been the inspiration for the flood mythology" (Ryan and Pitman, 1998). The marine incursion, caused by the rising level of the Mediterranean, apparently occurred around 7,600 years ago. It remains an active subject of debate among geologists, with subsequent evidence discovered to both support and refute the existence of the flood, while

707-593: A different cause. According to Tchepalyga, global warming beginning from about 16,000 BP caused the melting of the Scandinavia Ice Sheet , resulting in massive river discharge that flowed into the Caspian Sea , raising it to as much as 50 metres (160 ft) above normal present-day levels. The Sea of Azov rose so high that it overflowed into the Caspian Sea. The rise was extremely rapid and

808-558: A downstream translation of freshening. During the period of the melting of the Laurentide Ice Sheet, three of the largest periods of Northern Hemisphere cooling occurred directly following large freshwater fluxes from Lake Agassiz. At the time, Lake Agassiz was the largest lake in North America, and it intermittently expelled massive volumes of water. For perspective, it periodically covered over one million km , and

909-444: A few years. The implication of this is that the rate of outflow would have been extremely high, especially in comparison to values that have been found to be necessary for disruptions of the thermohaline circulation (~1 Sv over ten years, or 0.1 Sv over about a century). The greatest outburst of Lake Agassiz happened to be its last drawdown, occurring about 8.4 ka calendar years when it had joined glacial Lake Ojibway . Lake Ojibway

1010-540: A flattened-out Antarctica with a sheet of water 10 metres (33 ft) deep. That volume was added to the world's oceans in a matter of months. The detailed timing and rates of change after the onset of melting of the great ice-sheets are subjects of continuing study. A theory proposed by Andrey Tchepalyga of the Russian Academy of Sciences dates the flooding of the Black Sea basin to an earlier time and from

1111-555: A freshwater outflow event was large enough that the water reached the ocean system, it caused changes in salinity that potentially affected ocean circulation and global climate . Freshwater flows could also accumulate to form continental glacial lakes , and this is another indicator of large-scale flooding . In contrast, periods of high global sea level (often during interglacials ) could cause marine water to breach natural dams and flow into bodies of freshwater. Changes in salinity of freshwater and marine bodies can be detected from

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1212-573: A large scale. If freshwater fluxes into the Northern Atlantic Ocean were stopped once the North Atlantic Deep Water production had completely ceased, production did not begin again. The above modeling studies suggest that even if the fluxes during the major outburst events of Lake Agassiz occurred over longer time periods, thus being weaker in magnitude, they still would have possibly been sufficient to trigger

1313-479: A large-scale cooling around 8.4 – 8.0 ka calendar years As such, it has been concluded that this cold event was likely caused by the final large drawdown and associated massive outburst from Lake Agassiz to the North Atlantic Ocean. Even though more than 10 times the amount of water was released at this point than during the Younger Dryas, and the thermohaline circulation was consequently impacted,

1414-446: A major goal in the 1740s by turning out the first Russian scholar members, Stepan Krasheninnikov and Mikhail Lomonosov . The academy's charter in 1747 brought some changed to the academy's organization which stood until the end of the century. Among some of the changes were Russian and Latin as the official languages, a push to translate literature into Russian, and restrictive working hours for faculty. The charter also emphasized

1515-536: A megaflood (Gilbert, 1890) describes this event. The last of the North American proglacial lakes, north of the present Great Lakes, has been designated Glacial Lake Ojibway by geologists. It reached its largest volume around 8,500 years ago, when joined with Lake Agassiz. But its outlet was blocked by the great wall of the glaciers and it drained by tributaries, into the Ottawa and St. Lawrence Rivers far to

1616-595: A short time later, a flux of 1.6 Sv (again occurring over one year) would have resulted. Prior to its final drawdown, the first major outburst of Lake Agassiz occurred around 12.9 ka calendar years and involved the routing of water east into the Great Lakes and the St. Lawrence. Assuming this occurred over a one-year period, the flux was 0.30 Sv. Then, another outburst took place around 11.7 ka calendar years and contained two events total. First, water flooded southward through

1717-407: A sudden drop of sea surface temperatures and a weaker thermohaline circulation. It was nearly 200 years before the ocean system returned to normal in this case. Another modeling study by the same research group indicated that if just 0.1 Sv of freshwater was added to high North Atlantic Ocean latitudes, sea surface temperatures could drop by as much as 6 °C in less than 100 years, also weakening

1818-464: A very short period of time. Given the fact that the outflow channel for this case was not nearly as narrow as in other outbursts, it is likely that the lake indeed drew down very rapidly. If the outburst occurred in one year, the flux is estimated to be 5.2 Sv. An alternative to the scenario of the Lake Agassiz outburst describes an initial outburst from the western portion of the lake, instead of

1919-458: A year, reducing the estimated flux, because of erosion to outflow channels due to the first two major fluxes. Subsequent flooding occurred after these three events and before the final outburst, but they are not considered, as their resultant fluxes were generally weaker and did not precede substantial cooling. In order to gain an idea of the effect that large freshwater fluxes into the ocean would have on global ocean circulation, numerical modeling

2020-521: Is considered very prestigious. In the years 2005–2012, the academy had approximately 500 full and 700 corresponding members. But in 2013, after the Russian Academy of Agricultural Sciences and the Russian Academy of Medical Sciences became incorporated into the RAS, a number of the RAS members accordingly increased. The last elections to the renewed Russian Academy of Sciences were organized from May 30 to June 3, 2022. As of November 2, 2024,

2121-509: Is needed. Of particular importance to the cases of freshwater fluxes from Lake Agassiz are the locations of their entry into the ocean and the rapidity at which they entered. The likely outcome is that the fluxes themselves, combined with the effect of the re-direction of the Agassiz Baseline flow, had an appreciable impact on ocean circulation and consequently climate. Some simulations of North Atlantic Deep Water formation confirm that

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2222-479: Is still much to learn. Regarding the freshening episodes of the Champlain Sea, the exact locations and timing of drainage into the sea still remain in question. These factors, in turn, affected how ocean circulations, and potentially climate, changed. What is known of the drainage of Lake Agassiz is largely based on modeling studies. As in the case of the Champlain Sea, the magnitude, timing, and direction of

2323-422: Is the lake overflow that caused one of the worst landslide-related disasters in history on June 10, 1786. A landslide dam on Sichuan's Dadu River , created by an earthquake ten days earlier, burst and caused a flood that extended 1,400 km (870 mi) downstream and killed 100,000 people. Postglacial rebound changes the tilt of ground. In lakes, this means that shores sink in the direction farther away from

2424-543: The Channeled Scablands . Lake Bonneville , a pluvial lake , burst catastrophically in the Bonneville Flood about 14,500 years ago, due to its water overflowing and washing away a sill composed of two opposing alluvial fans which had blocked a gorge . Lake Bonneville was not a glacial lake, but glacial age climate change determined the lake level and its overflow. The first scientific report of

2525-674: The Mississippi River to the Gulf of Mexico was re-routed into the Great Lakes and the St. Lawrence River about 12.8 ka calendar years ago. There is uncertainty as to whether this change was enough to trigger the Younger Dryas, but the runoff through the Mississippi River could have pre-conditioned the thermohaline circulation prior to the cold period and outburst. Additionally, if the outburst at 12.9 ka calendar years

2626-751: The Moscow Institute of Physics and Technology , make use of the staff and facilities of many institutes of the RAS (as well as of other research institutions); the MIPT faculty refers to this arrangement as the "Phystech System". From 1933 to 1992, the main scientific journal of the Soviet Academy of Sciences was the Proceedings of the USSR Academy of Sciences ( Doklady Akademii Nauk SSSR ); after 1992, it became simply Proceedings of

2727-660: The Preboreal Oscillation . It is thought by some that this period was caused by freshwater outbursts from the Baltic Ice Lake to the Nordic Sea , but this cooling also closely followed the Lake Agassiz outbursts that occurred 11.7 and 11.2 ka calendar years. The outflow from Lake Agassiz at these times resulted in similar freshwater flux values into the Arctic Ocean as have been estimated from

2828-501: The Soviet space program . In 1957 the first satellite was launched, in 1961 Yury Gagarin became the first person in space, and in 1971 the first space station Salyut 1 began its operation. Discoveries were also made in the nuclear branch and in other fields of physics. Furthermore, the academy participated in opening new universities or new study programs in the already existed universities, whose best absolvents started their career at

2929-619: The Strait of Gibraltar into the desiccated Mediterranean basin , following the Messinian salinity crisis during which it repeatedly became dry and re-flooded, dated by consensus to before the emergence of modern humans. The Mediterranean did not dry out during the most recent glacial maximum . Sea level during glacial periods within the Pleistocene is estimated to have dropped only about 110 to 120 metres (361 to 394 ft). In contrast,

3030-499: The mathematicians Leonhard Euler (1707–1783), Anders Johan Lexell , Christian Goldbach , Georg Bernhard Bilfinger , Nicholas Bernoulli (1695–1726) and Daniel Bernoulli (1700–1782), botanist Johann Georg Gmelin , embryologists Caspar Friedrich Wolff , astronomer and geographer Joseph-Nicolas Delisle , physicist Georg Wolfgang Kraft , historian Gerhard Friedrich Müller and English Astronomer Royal Nevil Maskelyne (1732–1811). Expeditions to explore remote parts of

3131-552: The Academy of Sciences ( Doklady Akademii Nauk ). The academy is also increasing its presence in the educational area. In 1990, the Higher Chemical College of the Russian Academy of Sciences was founded, a specialized university intended to provide extensive opportunities for students to choose an academic path. The academy gives out a number of different prizes, medals and awards among which: The academy

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3232-657: The Baltic Ice Lake to the Nordic Sea, so it seems likely that Lake Agassiz at least contributed to the Preboreal Oscillation cooling. However, this period of cooling was not as intense as that during the Younger Dryas for a few reasons. First, the outburst from Lake Agassiz during the Preboreal Oscillation flooded into the Arctic, instead of the North Atlantic Ocean as during the Younger Dryas. Also, as

3333-623: The Caspian basin could not contain all the floodwater, which flowed from the northwest coastline of the Caspian Sea, through the Kuma-Manych Depression and Kerch Strait into the Black Sea basin. By the end of the Pleistocene this would have raised the level of the Black Sea by some 60 to 70 metres (200 to 230 ft) 20 metres (66 ft) below its present-day level, flooding large areas that were formerly available for settlement or hunting. Tchepalyga suggests this may have formed

3434-403: The Champlain Sea, conditions were brackish (mixture of fresh and salt water) about 10.8 ka BP. The δ C value of a core sample Melo-1 (see Fig. 3 for location) indicates the amount of light carbon that is present. Biota preferentially intake light carbon, so the more that is present in a sample, the more biota that was present at that time. Additionally, core samples from the Champlain Sea indicate

3535-536: The Champlain Sea. However, uncertainty still exists regarding the location of the drainage and its exact effects on ocean salinity. Because of the Champlain Sea's openness to the Atlantic Ocean, changes in the salinity of the Champlain Sea could have translated into the Northern Atlantic, thus possibly causing changes in ocean circulation and climate. In fact, the melting of the Laurentide Ice Sheet

3636-666: The FASO was incorporated into Russia's new Ministry of Science and Higher Education. The latter was created by splitting the Ministry of Education and Science . Mikhail Kotyukov , who had been head of FASO since its creation, was named head of the new Ministry of Science and Higher Education. In June 2023, the RAS opened the Modern Ideology of China Research Laboratory within its Institute of China and Contemporary Asia to study Xi Jinping Thought . The following persons occupied

3737-641: The German philosopher Christian Wolff , a correspondent of Leibniz, in the early 1720s and unsuccessfully offered him the Vice-Presidency of the academy. While Wolff declined a position in the academy, he did invite western scholars to work at the academy to improve higher education within the Russian Empire as outlined in Leibniz's letters. Foreign scholars invited to work at the academy included

3838-399: The Great established the academy (then the St. Petersburg Academy of Sciences) in 1724 with guidance from Gottfried Leibniz . From its establishment, the academy benefitted from a slate of foreign scholars as professors; the academy then gained its first clear set of goals from the 1747 Charter. The academy functioned as a university and research center throughout the mid-18th century until

3939-607: The Mississippi River Valley and into the Gulf of Mexico. Within a few years, flood water flowed to the northwest and into the Arctic Ocean. These two stages resulted in a total flux of 0.29 Sv (again, over one year). The fourth major flooding event that preceded a cooling period occurred about 11.2 ka calendar years. In this event, water flowed to the south and then the northwest, resulting in a flux of 0.19 Sv over one year. This event probably would have spanned more than

4040-425: The RAS members signalized their intention not to join the new academy if the reform is run as planned in the draft. Some leading scientists (including Pierre Deligne , Michael Atiyah , Mumford , and others) wrote open letters which referred to the planned reform of the RAS as "shocking" and even "criminal". In this situation, the draft was softened in some details—e.g., there remained no words about "dissolution" in

4141-519: The RAS while creating a new "public-governmental" organization with the same name. The RAS would be fused with two other Russian national academies— Russian Academy of Agricultural Sciences  [ ru ] and Russian Academy of Medical Sciences , with all members of all academies acquiring equal status as academicians. The law also created a new government agency: Federal Agency for Scientific Organizations  [ ru ] (FASO). FASO would take control of all buildings and other property of

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4242-447: The RAS" (163 scientists) or even "RAS professor, academician of the RAS" (16 scientists). The RAS consists of 13 specialized scientific divisions, four territorial branches and 15 regional scientific centers. The academy has numerous councils, committees, and commissions, all organized for different purposes. The Russian Academy of Sciences comprises a large number of research institutions, including: Member institutions are linked via

4343-579: The RAS: full members ( academicians ), corresponding members, and foreign members. Academicians and corresponding members must be citizens of the Russian Federation when elected. However, some academicians and corresponding members were elected before the collapse of the USSR and are now citizens of other countries. Members of RAS are elected based on their scientific contributions – election to membership

4444-766: The St. Petersburg Academy of Science a year before he died, in January 1724 and the Senate decree of February 8, 1724 implemented the academy. It was modeled after the centralized structure of the Paris Academy and the Berlin Academy of Sciences . These model institutions had led to an educated society of philosophical men, something Peter wanted in Russia. In particular, the Berlin Academy of Sciences

4545-669: The Supreme Soviet of the USSR in 1974, "among the deputies of the Council of the Union, there were 22 scientists from the Academy of Sciences of the USSR, the academies of sciences of the Union republics, and branch academies." In 1989, Andrei Sakharov became a People's Deputy of the USSR. Many scientists have worked in the State Duma of the Russian Federation - among the most famous are the physicist Zhores Alferov (deputy from

4646-602: The USSR over Nazi Germany . During and after the war, the academy was involved in the Soviet atomic bomb project ; due to its success and other achievements in military techniques, the USSR became one of the superpowers in the Cold War era. At the end of the 1940s, the academy consisted of eight divisions (Physico-Mathematical Science, Chemical Sciences, Geological-Geographical Sciences, Biological Science, Technical Science, History and Philosophy, Economics and Law, Literature and Languages); three committees (one for coordinating

4747-528: The United States. Some excellent university graduates who could have become promising researchers also switched to other activities, predominately in commerce. The Russian Academy practically lost a generation of people born from the mid-1960s to mid-1970s; this age category is now underrepresented in all research institutes. In the 2000s, the situation in the Russian science and technology has improved,

4848-646: The academic system as he had seen in Western Europe, although he could not get a meeting with Peter during Peter's first European tour. Leibniz did, however, begin correspondence with Peter's advisors where he discussed different plans to achieve the westernization of Russia. Leibniz suggested an education reform which divided schools, universities, and academies, as well as creating new academies and schools. Also, Leibniz suggested creating an arts and sciences institution with faculty consisting of leading foreign scholars. Following Leibniz's advice, Peter founded

4949-569: The academy had 1873 living Russian members (full: 802, corresponding: 1071) and about 430 foreign members. Since 2015, the academy also awards, on a competitive basis, the honorary scientific rank of a RAS Professor to the top-level researchers with Russian citizenship. Now there are 713 scientists with this rank. RAS professorship is not a membership type but its holders are considered as possible candidates for membership; some professors became members already in 2016, in 2019 or in 2022 and are henceforth titled "RAS professor, corresponding member of

5050-422: The academy instead of bureaucratic rule. Also, in the second half of the 18th century, Russian scholars grew in number among the faculty of the academy. To heal the growing internal German versus Russian conflict of the faculty, Catherine the Great convinced Euler to return to St Petersburg and head the academy in 1766, where he stayed until he died in 1783. Catherine the Great's son Paul I's short reign marked

5151-721: The academy published 20 volumes of their academic journal called Novi Commentarii Academiae Scientiarum Imperialis Petropolitanae . The majority of Russian scientific research in the 18th century was done by members of the academy. Originally called The Saint Petersburg Academy of Sciences ( Russian : Петербургская академия наук ), the organization went under various names over the years, becoming The Imperial Academy of Sciences and Arts (Императорская академия наук и художеств; 1747–1803), The Imperial Academy of Sciences (Императорская академия наук; 1803–1836), and finally, The Imperial Saint Petersburg Academy of Sciences (Императорская Санкт-Петербургская академия Наук, from 1836 and until

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5252-488: The academy to be a model for Russia. Since the academy was under the Tsar, the presidents, vice-presidents, directors, and vice-directors were all appointed by the crown. Catherine I started this precedent which lasted until the end of the Russian Empire. The academy hit hard times during Empress Anna's rule. A low of 6 students remained in 1744 and the teaching was in German, contrary to Peter I's wishes. The academy achieved

5353-491: The academy, opening it in December 1725. Mathematics, physical sciences, and humanities were the three departments which made up the academy upon its opening. The academy also contained a university and secondary school, promoting higher education in Russia. As such, the initial 17 scholars had to teach and administer research. They were a portion of the 84 Academy staff in 1726 There were also student assistants who helped

5454-456: The academy. In addition, all RAS academic institutes were removed from academy control. Instead, the new government agency FASO was empowered to "evaluate", relying on its own criteria, the efficiency of research institutes and rearrange ineffective ones. The draft law, which, in its initial form, would have fundamentally changed the system of science organization in Russia, provoked conflicts and protests within academic circles. A large group of

5555-460: The added effects of salinity. Before a determination of the effects of freshwater fluxes from Lake Agassiz on global ocean circulation and climate can be made, it is important to establish its baseline flux value. This is essentially a natural background flux of water from the lake. From 21.4 – 9.5 ka calendar years, this baseline flux for Lake Agassiz has been found to be about 0.3 to 0.4 Sverdrup , or Sv, in total (1 Sv = 1 x 106 m s ). This value

5656-630: The analysis of organisms that inhabited those bodies at a given time, as certain organisms are more suited to live in either fresh or saline conditions. The Champlain Sea was a body of salt water that underwent several episodes of freshening. Two main events were observed 11.4 and 13.0 ka BP (thousand years Before Present). Faunal and foraminifera indicators in core samples taken from the sea can be used to estimate its salinity throughout time. The ages of various portions and depths of core samples are determined through radiocarbon dating . The Champlain Sea

5757-609: The areas of the modern lakes, but their drainage sometimes passed south, into the Mississippi system; sometimes into the Arctic, or east into the Atlantic. The most famous of these proglacial lakes was Lake Agassiz . As ice-dam configurations failed, a series of great floods were released from Lake Agassiz, resulting in massive pulses of freshwater added to the world's oceans. The Missoula Floods of Oregon and Washington states were also caused by breaking ice dams, resulting in

5858-668: The barrier failed or was overtopped, loosing a catastrophic flood that permanently diverted the Rhine into the English Channel and replacing the "Isthmus of Dover" watershed by a much lower watershed running from East Anglia east then southeast to the Hook of Holland and (as at modern sea level) separated Britain from the continent of Europe; a sonar study of the sea bed of the English Channel published in Nature , July 2007, revealed

5959-456: The basis for legends of the great Deluge . The barrier across Bab-el-Mandeb , between Ethiopia and Yemen, seems to have been the source of outbreak flooding similar to that found in the Mediterranean. The Lake Toba event, approximately between 69,000 and 77,000 years ago, caused a massive drop in sea levels, exposing the barrier and enabling modern Homo sapiens to leave Africa via a route other than Sinai. The finding of saline evaporites on

6060-541: The circulation resulting from differences in ocean temperature and salinity. For example, a large portion of deep water is created in the Arctic as surface water adjacent to glaciers that is more dense than surrounding water (because it is influenced by recent cold melt water, cooled by evaporation from surface winds, and is saline) sinks to the deep ocean. However, if a large enough quantity of this water becomes less saline, deep ocean formation would be primarily through thermal differences, which tend to be less dominant than with

6161-531: The cooling effect was relatively small in intensity. It is thought that this is due to two reasons: 1) the ocean was already in a warm interglacial mode, and 2) the water flowed through the Hudson Strait and entered the North Atlantic Ocean nearly 2000 km to the north of where the outflow had entered the ocean before the Younger Dryas. Though much is understood about the interactions between large-scale paleoflooding, ocean circulation, and climate, there

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6262-523: The country had Academy scientists as their leaders or most active participants. These included Vitus Bering 's Second Kamchatka Expedition of 1733–1743, expeditions to observe the 1769 transit of Venus from eight locations in Russian Empire , and the expeditions of Peter Simon Pallas (1741–1811) to Siberia . The expeditions led to the creation of an atlas of Russia and to research in astronomy, geography, and fauna and flora. From 1750 to 1777,

6363-446: The depth of the Strait of Gibraltar where the Atlantic Ocean enters ranges between 300 and 900 metres (980 and 2,950 ft). Paleoflooding The phenomenon of paleoflooding is apparent in the geologic record over various spatial and temporal scales. It often occurred on a large scale, and was the result of either glacial ice melt causing large outbursts of freshwater, or high sea levels breaching bodies of freshwater. If

6464-632: The discovery of unmistakable marks of a megaflood on the English Channel seabed: deeply eroded channels and braided features have left the remnants of streamlined islands among deeply gouged channels where the collapse occurred. A catastrophic flood refilled the Mediterranean Sea 5.3 million years ago, at the beginning of the Zanclean age that ended the Messinian salinity crisis . The flood occurred when Atlantic waters found their way through

6565-518: The end of the empire in 1917). A separate organization, called the Russian Academy ( Russian : Академия Российская ), was created in 1783 to work on the study of the Russian language . Presided over by Princess Yekaterina Dashkova (who at the same time was the Director of the Imperial Academy of Arts and Sciences, i.e., the country's "main" academy), the Russian Academy was engaged in compiling

6666-546: The exception of the Russian SFSR ), in many cases delegating prominent scientists to live and work in other republics. In the case of Ukraine, its academy was formed by the local Ukrainian scientists and prior to occupation of the Ukrainian People's Republic by Bolsheviks . These academies were: Among the most important achievements of the academy of the second half of the 20th century, there is, first of all,

6767-588: The expertise of the academy would be applied to addressing questions of state construction, while in return the Soviet government would give the academy financial and political support. The most important activities of the academy in the 1920s included an investigation of the large Kursk Magnetic Anomaly , of the minerals in the Kola Peninsula , and participation in the GOELRO plan targeted electrification of

6868-401: The floor of the Red Sea confirms that this dam has functioned at various periods in the past. Rising sea levels during the Flandrian transgression (and in earlier interglacial periods) suggest that this area may have been subject to outburst flooding. Originally there was an isthmus across the Strait of Dover . During an earlier glacial maximum, the exit from the North Sea was blocked to

6969-416: The fluxes from Lake Agassiz greatly influence subsequent consequences. Several questions that remain include, but are not limited to, the following: Are estimates of the baseline flux of Lake Agassiz correct, and are variations in it accurately accounted for? Over what time period, exactly, did the different drainage episodes last? How much water was actually drained during these episodes, and where did it enter

7070-468: The form of a federal state budgetary institution chartered by the Government of Russia . In 2013, the Russian government restructured RAS, assigning control of its property and research institutes to a new government agency headed by Mikhail Kotyukov . As of November 2017 , the academy included 1,008 institutions and other units; in total about 125,000 people were employed of whom 47,000 were scientific researchers. There are three types of membership in

7171-436: The former maximum depth of ice. When the lake rests against an esker , water pressure increases with the increased depth. The esker may then fail under the load and burst, creating a new outflow. Lake Pielinen in Finland is an example of this. A rising sea flood, the proposed and much-discussed refilling of the freshwater glacial Black Sea with water from the Aegean , has been described as "a violent rush of salt water into

7272-479: The geological past of the Earth, however, geological research has shown that much larger events have occurred. In the case of outburst floods, such floods are typically linked to the collapse of a barrier which formed a lake. They fall in the following classification according to the mechanism responsible: Examples where evidence for large ancient water flows has been documented or is under scrutiny include: An example

7373-487: The government announced a modernization campaign . Nevertheless, according to the Russian Academy of Sciences, total R&D spending in 2013 still hovered about 40% below the pre-crisis 1990 levels. Furthermore, a lack of competition, decayed infrastructure and continuing, though slightly reduced, brain drain play their part. On June 28, 2013, the Russian Government announced a draft law that would dissolve

7474-424: The hope for Russian Academy graduates to replace all the foreign scholars in time. Most of the secondary school graduates went into civil service instead of continue to the university. The university part of the academy gradually deteriorated and eventually died by 1767. During Catherine the Great's rule, she enacted reforms to improve the academy for scholars. She created a commission of academy faculty to lead

7575-670: The newly created outflow channels, eventually making its way to the open ocean through one of four major routes. These routes have been identified to be the Mississippi River Valley , the St. Lawrence River Valley , the Mackenzie River Valley , and the Hudson Strait (Fig. 2). It is thought that these outflow events, leading to the drawdown of Lake Agassiz, could have lasted as little as a few months to

7676-554: The north by an ice dam , and the water flowing out of rivers backed up into a vast lake with freshwater glacial melt on the bed of what is now the North Sea. A gently upfolding chalk ridge linking the Weald of Kent and Artois , perhaps some 30 metres (100 feet) higher than the current sea level, contained the glacial lake at the Strait of Dover . At some time, probably around 425,000 years ago and again around 225,000 years later

7777-403: The oceans and the thermohaline circulation are affected by these fluxes. Small increases in freshwater fluxes have been shown to reduce the thermohaline circulation and in some cases could halt the production of North Atlantic Deep Water all together. One particular model allowed for a flux of 1 Sv of freshwater into high latitudes of the Atlantic Ocean for a period of 10 years, which resulted in

7878-417: The open ocean? What was the exact effect of drainage on the formation of North Atlantic Deep water, the thermohaline circulation, and climate? There are two proposed scenarios for the final drawdown of Lake Agassiz, so which one, if either, is right? The above are just some of the challenges faced when attempting to reconstruct events in Earth's history. Though it is a difficult field of study, advancements in

7979-525: The period leading up to the Preboreal Oscillation was interstadial to interglacial, the thermohaline circulation would have been more stable than during the Younger Dryas. Finally, the North Atlantic thermohaline circulation was not being pre-conditioned preceding the Preboreal Oscillation, as meltwater from Lake Agassiz was not being routed to the Gulf of Mexico. Analysis of Greenland ice cores , ocean core samples, and other sources have revealed

8080-423: The position of the academy's President (or, sometimes, Director): The last presidential elections in the academy (and also elections of the presidium) were organized on September 25–28, 2017. Initially the event was planned for March 2017, but unexpectedly all candidates retracted their nominations, and the elections were postponed. Scientists of the academy were repeatedly elected deputies of various levels. In

8181-612: The research institutes of the academy. After the collapse of the Soviet Union , by decree of the President of Russia of December 2, 1991, the academy again became the Russian Academy of Sciences , inheriting all facilities of the USSR Academy of Sciences in the territory of the Russian Federation. The crisis of the 1990s in the post-Soviet Russia and a consequent drastic reduction of the state support for science have forced many scientists to leave Russia for Europe, Israel or

8282-400: The scholars and taught in the secondary school. 112 students ages 5–18 made up the total first year enrollment in 1726. 76 of the 112 students were Russian while the other 36 students were foreign. The academy did not have an official charter until 1747. Peter I did lay out the goals for the academy in a document signed before his death called the "Project". In the document, Peter wished for

8383-596: The scientific work of the Academies of the Republics, one for scientific and technical propaganda, and one for editorial and publications), two commissions (for publishing popular scientific literature, and for museums and archives), a laboratory for scientific photography and cinematography and Academy of Science Press departments external to the divisions. The Academy of Sciences of the USSR helped to establish national Academies of Sciences in all Soviet republics (with

8484-417: The single outburst on its eastern edge as detailed above. In this case, it is hypothesized that a part of the Laurentide Ice Sheet might have remained over western Agassiz that prevented total drainage during the first episode to the east. Approximately 113,000 km was expelled initially to the east, resulting in a flux of 3.6 Sv (if it occurred in one year). When the western portion of Lake Agassiz drained

8585-685: The six-volume Academic Dictionary of the Russian Language (1789–1794). The Russian Academy was merged into the Imperial Saint Petersburg Academy of Sciences in 1841. Shortly after the October Revolution , in December 1917, Sergey Fedorovich Oldenburg , a leading ethnographer and political activist in the Kadet party, met with Vladimir Lenin to discuss the future of the academy. They agreed that

8686-447: The south. About 8,300 to 7,700 years ago, the melting ice dam over Hudson Bay 's southernmost extension narrowed to the point where pressure and its buoyancy lifted it free, and the ice-dam failed catastrophically. Lake Ojibway's beach terraces show that it was 250 metres (820 ft) above sea level. The volume of Lake Ojibway is commonly estimated to have been about 163,000 km (39,000 cu mi), more than enough water to cover

8787-492: The technical fields, was done. However, on the other hand, in these very times, many scientists underwent repressions for ideological reasons. In the years of the Second World War , the Soviet Academy of Sciences made a big contribution to a development of modern weapons – tanks (new series of T-34 ), airplanes , degaussing the ships (for protection against the naval mines ) etc. – and therefore to victory of

8888-545: The text—and approved on September 27, 2013. In 2014, Putin announced more changes to science funding that reduced RAS power while increasing that of the government. In 2017, the election of the RAS president was also brought under government control. At the General Meeting of the RAS in March 2018, the RAS president (that time) Alexander Sergeev said that the academy enters now the post-reform period. In May 2018,

8989-595: The theory that it is the basis of later flood myths is not proven. Flooding of this area scattered peoples to both sides of the gulf depression. It was an area fed by four rivers. Rose calls it the "Gulf Oasis" which may have been a demographic refuge fed by the Tigris, Euphrates, Karun, and Wadi Batin rivers. It was suggested to be an area of freshwater springs and rivers. In North America , during glacial maximum, there were no Great Lakes as we know them, but "proglacial" (ice-frontage) lakes formed and shifted. They lay in

9090-408: The thermohaline circulation, albeit less so than with higher freshwater fluxes. Additionally, it has been found from a separate study that a freshwater flux of 0.53 Sv into the North Atlantic Ocean in the absence of an existing thermohaline circulation could reduce North Atlantic Deep Water production by 95% in about a century. Large fluxes such as this are capable of cooling the oceans and climate on

9191-523: The understanding of proxies for, and indicators of, certain environmental parameters in the geologic record are constantly being made. Russian Academy of Sciences The Russian Academy of Sciences ( RAS ; Russian : Росси́йская акаде́мия нау́к (РАН) Rossíyskaya akadémiya naúk ) consists of the national academy of Russia; a network of scientific research institutes from across the Russian Federation; and additional scientific and social units such as libraries, publishing units, and hospitals. Peter

9292-491: The university was dissolved, leaving research as the main pillar of the institution. The rest of the 18th century continuing on through the 19th century consisted of many published academic works from Academy scholars and a few Academy name changes, ending as The Imperial Saint Petersburg Academy of Sciences right before the Soviet period. Now headquartered in Moscow, the academy (RAS) is a non-profit organization established in

9393-468: The whole country. In 1925 the Soviet government recognized the Russian Academy of Sciences as the "highest all-Union scientific institution" and renamed it the Academy of Sciences of the Soviet Union . In 1934, the academy headquarters moved from Leningrad to the capital, Moscow. The Stalin years were marked by a rapid industrialisation of the Soviet Union for which a great deal of research, mainly in

9494-526: Was a culmination of Emperor Peter the Great 's inspiration from his tours to Western Europe and its higher education centers along with the beginning of his correspondence with Gottfried Leibniz , a philosopher, mathematician, and diplomat. Peter's Western European travels introduced him to the new inventions and ideas of the Enlightenment period. Leibniz was attracted to Peter's desire to promote education and science in Russia through modernization of

9595-399: Was actually as intense as 0.30 Sv, its combination with the diversion of Agassiz drainage through the St. Lawrence River into the North Atlantic Ocean was likely the cause of the Younger Dryas. The value of 0.30 Sv through the St. Lawrence River would have been significant, as the baseline drainage was only 0.047 Sv through that river. The next cooling to follow the Younger Dryas phase was

9696-567: Was calculated using hydrological numerical model simulations and accounts for melt water and precipitation runoff. In reality, it is understood that this value is variable, so freshwater fluxes into the open ocean and their effect on thermohaline circulation, ocean circulations, and global climate would vary as well. Considering the enormity of Lake Agassiz, changes in the make-up of its shores (beaches, cliffs), or strandlines, could result in very massive outflows. These changes were often sudden, causing thousands of cubic kilometers of water to exit via

9797-549: Was founded by Leibniz, exemplary of the influence which Leibniz had on the creation of the St Petersburg Academy of Science. The Paris Academy was administered directly by the King, which inspired Peter to make himself the supreme head of the St Petersburg Academy of Science, although there could be an academy president. Peter's widow and Empress Catherine I followed through with the establishment and formation of

9898-482: Was located on the Laurentide Ice Sheet margin in the southeastern portion of the Hudson Bay basin. The total surface area of the merged lake was approximately 841,000 km . The outburst was caused by a breach in the ice sheet over the Hudson Bay, and it is estimated that if this lake was completely drawn down from its maximum depth, about 163,000 km of water would be released into the North Atlantic Ocean in

9999-578: Was located to the north of present-day New York and Vermont , on the southern fringes of Quebec and was open to the Northern Atlantic Ocean on its northeast arm. During the last deglaciation as the Laurentide Ice Sheet retreated, two major glacial lakes formed to the west of the Champlain Sea – Lake Agassiz and Lake Algonquin (Fig. 1). As these lakes continued to expand, freshwater flooded eastward toward and into

10100-415: Was often larger than 150,000 km over its 4000-year history. If the flux of freshwater into the open ocean was great enough, it could have had a large effect on the formation of North Atlantic Deep Water . That is to say, North Atlantic Deep Water formation could have periodically completely ceased, and the thermohaline circulation could have shut down. Basically, the thermohaline circulation refers to

10201-405: Was so extensive that its melt water entered the Gulf of Mexico , Arctic Ocean , and Hudson Bay (Fig. 2) in addition to the Champlain Sea and the Atlantic Ocean. Terrestrial plant material, seeds, and marine shells from Champlain Sea core samples have been used as proxies for paleosalinity . By studying δ C (change in carbon-13) of marine mollusks, it can be inferred that when they existed in

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