Iron Age Archaeological period The Iron Age is the final epoch of the three-age division of the prehistory and protohistory of humanity. It was preceded by the Stone Age (Paleolithic, Mesolithic, Neolithic) and the Bronze Age (Chalcolithic). The concept has been mostly applied to Iron Age Europe and the Ancient Near East, but also, by analogy, to other parts of the Old World. The duration of the Iron Age varies depending on the region under consideration. The Iron Age is taken to end, also by convention, with the beginning of the historiographical record. In the Indian sub-continent, the Iron Age is taken to begin with the ironworking Painted Gray Ware culture. History of the concept[edit] The time and context of this Iron Age era varied by geography or country.[2] Please note that classically, it is said that this era occurred in the 12th century BC.[3] Chronology[edit] [edit] Smelted iron appears sporadically in the archeological record from the middle Bronze Age. Ancient Near East[edit] Egypt[edit]
Global-warming potential Global-warming potential (GWP) is a relative measure of how much heat a greenhouse gas traps in the atmosphere. It compares the amount of heat trapped by a certain mass of the gas in question to the amount of heat trapped by a similar mass of carbon dioxide. A GWP is calculated over a specific time interval, commonly 20, 100 or 500 years. GWP is expressed as a factor of carbon dioxide (whose GWP is standardized to 1). For example, the 20 year GWP of methane is 86, which means that if the same mass of methane and carbon dioxide were introduced into the atmosphere, that methane will trap 86 times more heat than the carbon dioxide over the next 20 years.[1] The substances subject to restrictions under the Kyoto protocol either are rapidly increasing their concentrations in Earth's atmosphere or have a large GWP. The GWP depends on the following factors: Thus, a high GWP correlates with a large infrared absorption and a long atmospheric lifetime. Calculating the global-warming potential[edit]
Ancient Rome In its approximately 12 centuries of existence, Roman civilization shifted from a monarchy to a classical republic and then to an increasingly autocratic empire. Through conquest and assimilation, it came to dominate Southern and Western Europe, Asia Minor, North Africa, and parts of Northern and Eastern Europe. Rome was preponderant throughout the Mediterranean region and was one of the most powerful entities of the ancient world. Ancient Roman society has contributed to modern government, law, politics, engineering, art, literature, architecture, technology, warfare, religion, language and society. By the end of the Republic, Rome had conquered the lands around the Mediterranean and beyond: its domain extended from the Atlantic to Arabia and from the mouth of the Rhine to North Africa. Founding myth The Roman poet Virgil recounted this legend in his classical epic poem the Aeneid. Kingdom Main article: Roman Kingdom Republic Main article: Roman Republic Punic Wars
Global climate model Climate models are systems of differential equations based on the basic laws of physics, fluid motion, and chemistry. To “run” a model, scientists divide the planet into a 3-dimensional grid, apply the basic equations, and evaluate the results. Atmospheric models calculate winds, heat transfer, radiation, relative humidity, and surface hydrology within each grid and evaluate interactions with neighboring points.[1] Note on nomenclature[edit] The initialism GCM stands originally for general circulation model. History: general circulation models[edit] Atmospheric vs oceanic models[edit] There are both atmospheric GCMs (AGCMs) and oceanic GCMs (OGCMs). Modelling trends[edit] A recent trend in GCMs is to apply them as components of Earth system models, e.g. by coupling to ice sheet models for the dynamics of the Greenland and Antarctic ice sheets, and one or more chemical transport models (CTMs) for species important to climate. Model structure[edit] Coupled atmosphere–ocean GCMs (AOGCMs) (e.g.
Slavs The Slavs are an Indo-European ethno-linguistic group living in Central Europe, Eastern Europe, Southeast Europe, North Asia and Central Asia, who speak the Indo-European Slavic languages, and share, to varying degrees, certain cultural traits and historical backgrounds. From the early 6th century they spread to inhabit most of Central and Eastern Europe and Southeast Europe.[27] Slavic groups also ventured as far as Scandinavia, constituting elements amongst the Vikings;[28][29] whilst at the other geographic extreme, Slavic mercenaries fighting for the Byzantines and Arabs settled Asia Minor and even as far as Syria.[30] Later, East Slavs (specifically, Russians and Ukrainians) colonized Siberia[31] and Central Asia.[32] Every Slavic ethnicity has emigrated to other parts of the world.[33][34] Over half of Europe's territory is inhabited by Slavic-speaking communities.[35] Ethnonym[edit] European countries where a Slavic language is the official one on the entire territory History[edit]
Climateprediction.net The project relies on the volunteer computing model using the BOINC framework where voluntary participants agree to run some processes of the project at the client-side in their personal computers after receiving tasks from the server-side for treatment. CPDN, which is run primarily by Oxford University in England, has harnessed more computing power and generated more data than any other climate modelling project.[4] It has produced over 100 million model years of data so far.[5] As of December 2010[update], there are more than 32,000 active participants from 147 countries with a total BOINC credit of more than 14 billion, reporting about 90 teraflops (90 trillion operations per second) of processing power.[6] Aims[edit] IPCC graphic of uncertainty ranges with various models over time. As shown in the graph above, the various models have a fairly wide distribution of results over time. The experiments[edit] Climateprediction.net screensaver under BOINC 5.4.9 History[edit] Explanation[edit]
High Middle Ages The High Middle Ages was the period of European history around the 11th, 12th, and 13th centuries (c. 1001–1300). The High Middle Ages were preceded by the Early Middle Ages and followed by the Late Middle Ages, which by convention end around 1500. The key historical trend of the High Middle Ages was the rapidly increasing population of Europe, which brought about great social and political change from the preceding era. By 1250 the robust population increase greatly benefited the European economy, reaching levels it would not see again in some areas until the 19th century. This trend was checked in the Late Middle Ages by a series of calamities, notably the Black Death but also including numerous wars and economic stagnation. From about the year 780 onwards, Europe saw the last of the barbarian invasions[1] and became more socially and politically organized.[2] The Carolingian Renaissance led to scientific and philosophical revival of Europe. Historical events and politics[edit]
Instrumental temperature record Instrumental global surface temperature record since widespread reliable measurements began in the late 19th century; see also [1] The X axis represents time, and the Y axis represents the temperature anomaly (departure from 1961-1990 baseline of 14.0°C, Jones et al. 1999). Watch how summer temperatures in the Northern Hemisphere change from 1955 to 2011. "Hot" (orange), "very hot" (red) "extremely hot" (brown) "average" (white), unusually "cold" (light blue), "very cold" (dark blue) and "extremely cold" (purple). The instrumental temperature record shows fluctuations of the temperature of earth's climate system. Global records databases[edit] Calculating the global temperature[edit] Average Monthly Land surface temperatures from February 2000 to December 2013. Average Monthly Sea surface temperatures from July 2002 to December 2013. Land surface temperature anomalies for a given month compared to the long-term average temperature of that month between 2000-2008. The U.S.
Late Middle Ages The Late Middle Ages was the period of European history generally comprising the 14th and 15th centuries (c. 1301–1500). The Late Middle Ages followed the High Middle Ages and preceded the onset of the early modern era (and, in much of Europe, the Renaissance). Around 1300, centuries of prosperity and growth in Europe came to a halt. A series of famines and plagues, such as the Great Famine of 1315–1317 and the Black Death, reduced the population to around half of what it was before the calamities.[1] Along with depopulation came social unrest and endemic warfare. France and England experienced serious peasant uprisings: the Jacquerie, the Peasants' Revolt, as well as over a century of intermittent conflict in the Hundred Years' War. Despite these crises, the 14th century was also a time of great progress within the arts and sciences. Combined with this influx of classical ideas was the invention of printing which facilitated dissemination of the printed word and democratized learning.
Early modern period In history, the early modern period of modern history follows the late Middle Ages of the post-classical era. Although the chronological limits of the period are open to debate, the timeframe spans the period after the late portion of the post-classical age (c. 1500), known as the Middle Ages, through the beginning of the Age of Revolutions (c. 1800) and is variously demarcated by historians as beginning with the Fall of Constantinople in 1453, with the Renaissance period, and with the Age of Discovery (especially with the discovery of America, but also with the discovery of the sea route to the East), and ending around the French Revolution in 1789. From a global standpoint, the most important feature of the early modern period was its globalizing character — it witnessed the exploration and colonization of the Americas and the rise of sustained contacts between previously isolated parts of the globe. The historical powers became involved in global trade. Early modern timeline[edit]