Spörer MinimumThe Spörer Minimum is a hypothesized 90-year span of low solar activity, from about 1460 until 1550, which was identified and named by John A. Eddy in a landmark 1976 paper published in Science titled "The Maunder Minimum". It occurred before sunspots had been directly observed and was discovered instead by analysis of the proportion of carbon-14 in tree rings, which is strongly correlated with solar activity. It is named for the German astronomer Gustav Spörer.
InterglacialAn interglacial period (or alternatively interglacial, interglaciation) is a geological interval of warmer global average temperature lasting thousands of years that separates consecutive glacial periods within an ice age. The current Holocene interglacial began at the end of the Pleistocene, about 11,700 years ago. During the 2.5 million years of the Pleistocene, numerous glacials, or significant advances of continental ice sheets, in North America and Europe, occurred at intervals of approximately 40,000 to 100,000 years.
Ming dynastyThe Ming dynasty (mɪŋ), officially the Great Ming, was an imperial dynasty of China, ruling from 1368 to 1644 following the collapse of the Mongol-led Yuan dynasty. The Ming dynasty was the last imperial dynasty of China ruled by the Han people, the majority ethnic group in China. Although the primary capital of Beijing fell in 1644 to a rebellion led by Li Zicheng (who established the short-lived Shun dynasty), numerous rump regimes ruled by remnants of the Ming imperial family—collectively called the Southern Ming—survived until 1662.
DiatomA diatom (Neo-Latin diatoma) is any member of a large group comprising several genera of algae, specifically microalgae, found in the oceans, waterways and soils of the world. Living diatoms make up a significant portion of the Earth's biomass: they generate about 20 to 50 percent of the oxygen produced on the planet each year, take in over 6.7 billion tonnes of silicon each year from the waters in which they live, and constitute nearly half of the organic material found in the oceans.
IcebreakerAn icebreaker is a special-purpose ship or boat designed to move and navigate through ice-covered waters, and provide safe waterways for other boats and ships. Although the term usually refers to ice-breaking ships, it may also refer to smaller vessels, such as the icebreaking boats that were once used on the canals of the United Kingdom. For a ship to be considered an icebreaker, it requires three traits most normal ships lack: a strengthened hull, an ice-clearing shape, and the power to push through sea ice.
Chesapeake BayThe Chesapeake Bay (ˈtʃɛsəpiːk ) is the largest estuary in the United States. The Bay is located in the Mid-Atlantic region and is primarily separated from the Atlantic Ocean by the Delmarva Peninsula, including parts of the Eastern Shore of Maryland, the Eastern Shore of Virginia, and the state of Delaware. The mouth of the Bay at its southern point is located between Cape Henry and Cape Charles. With its northern portion in Maryland and the southern part in Virginia, the Chesapeake Bay is a very important feature for the ecology and economy of those two states, as well as others surrounding within its watershed.
Year Without a SummerThe year 1816 is known as the Year Without a Summer because of severe climate abnormalities that caused average global temperatures to decrease by . Summer temperatures in Europe were the coldest of any on record between the years of 1766 and 2000. This resulted in major food shortages across the Northern Hemisphere. Evidence suggests that the anomaly was predominantly a volcanic winter event caused by the massive 1815 eruption of Mount Tambora in April in the Dutch East Indies (modern-day Indonesia).
Ice ageAn ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages and greenhouse periods, during which there are no glaciers on the planet. Earth is currently in the ice age called Quaternary glaciation. Individual pulses of cold climate within an ice age are termed glacial periods (or, alternatively, glacials, glaciations, glacial stages, stadials, stades, or colloquially, ice ages), and intermittent warm periods within an ice age are called interglacials or interstadials.
High Middle AgesThe High Middle Ages, or high medieval period, was the period of European history that lasted from AD 1000 to 1350. The High Middle Ages were preceded by the Early Middle Ages and were followed by the Late Middle Ages, which ended around AD 1500 (by historiographical convention). Key historical trends of the High Middle Ages include the rapidly increasing population of Europe, which brought about great social and political change from the preceding era, and the Renaissance of the 12th century, including the first developments of rural exodus and urbanization.
IcebergAn iceberg is a piece of freshwater ice more than 15 m long that has broken off a glacier or an ice shelf and is floating freely in open (salt) water. Smaller chunks of floating glacially-derived ice are called "growlers" or "bergy bits". The sinking of the Titanic in 1912 led to the formation of the International Ice Patrol in 1914. Much of an iceberg is below the surface, which led to the expression "tip of the iceberg" to illustrate a small part of a larger unseen issue. Icebergs are considered a serious maritime hazard.
