Bond events are North Atlantic

ice rafting Ice rafting is the transport of various materials by ice. Various objects deposited on ice may eventually become embedded in the ice. When the ice melts after a certain amount of drifting, these objects are deposited onto the bottom of the wate ...

events that are tentatively linked to climate fluctuations in the

Holocene The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene togeth ...

. Eight such events have been identified. Bond events were previously believed to exhibit a roughly cycle, but the primary period of variability is now put at .

Gerard C. Bond Gerard Clark Bond (May 20, 1940 – June 29, 2005) was an American geologist. Biography Bond received his Bachelor of Science degree at Capital University in Columbus, Ohio, where his father Ralph Bond was a Professor of Geology. He worked at t ...

of the

Lamont–Doherty Earth Observatory The Lamont–Doherty Earth Observatory (LDEO) is the scientific research center of the Columbia Climate School, and a unit of The Earth Institute at Columbia University. It focuses on climate and earth sciences and is located on a 189-acre (64 ...

Columbia University Columbia University (also known as Columbia, and officially as Columbia University in the City of New York) is a private research university in New York City. Established in 1754 as King's College on the grounds of Trinity Church in Manhatt ...

was the lead author of the 1997 paper that postulated the theory of 1470-year climate cycles in the Late Pleistocene and Holocene, mainly based on

petrologic Petrology () is the branch of geology that studies rocks and the conditions under which they form. Petrology has three subdivisions: igneous, metamorphic, and sedimentary petrology. Igneous and metamorphic petrology are commonly taught together ...

tracers of drift ice in the North Atlantic. However, more recent work has shown that these tracers provide little support for 1,500-year intervals of climate change, and the reported period was a statistical artifact. Furthermore, following publication of the Greenland Ice Core Chronology 2005 (GICC05) for the North GRIP ice core, it became clear that

Dansgaard–Oeschger event Dansgaard–Oeschger events (often abbreviated D–O events), named after palaeoclimatologists Willi Dansgaard and Hans Oeschger, are rapid climate fluctuations that occurred 25 times during the last glacial period. Some scientists say that th ...

s also show no such pattern. The North Atlantic

ice-rafting Ice rafting is the transport of various materials by ice. Various objects deposited on ice may eventually become embedded in the ice. When the ice melts after a certain amount of drifting, these objects are deposited onto the bottom of the wate ...

events happen to correlate with episodes of lowered lake levels in the Mid-Atlantic region of the United States, the weakest events of the

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an are ...

monsoon A monsoon () is traditionally a seasonal reversing wind accompanied by corresponding changes in precipitation but is now used to describe seasonal changes in atmospheric circulation and precipitation associated with annual latitudinal osci ...

for at least the past 9,000 years, and also correlate with most aridification events in the

Middle East The Middle East ( ar, الشرق الأوسط, ISO 233: ) is a geopolitical region commonly encompassing Arabia (including the Arabian Peninsula and Bahrain), Asia Minor (Asian part of Turkey except Hatay Province), East Thrace (Europ ...

for the past 55,000 years (both

Heinrich Heinrich may refer to: People * Heinrich (given name), a given name (including a list of people with the name) * Heinrich (surname), a surname (including a list of people with the name) *Hetty (given name), a given name (including a list of peo ...

and Bond events).

List

Most Bond events do not have a clear climate signal; some correspond to periods of cooling, but others are coincident with aridification in some regions. Gap between events has been estimated to be 1,000-1,500 years with Bond event # 4 as an outlying data point.

Influence in regional climate

Bond events have been detected in remote regions such as the central

Andes The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...

of South America. Up to six Bond cycles during the upper and middle

have been identified in three ice core records of the tropical Andes. The records were extracted from the summits of

Nevado Sajama Nevado Sajama (; ) is an extinct stratovolcano and the highest peak in Bolivia. The mountain is located in Sajama Province, in Oruro Department. It is situated in Sajama National Park and is a composite volcano consisting of a stratovolcano on t ...

, Nevado Huascarán and Nevado Illimani. The detected cycles were at 6400 years Before Present, 5500 years B.P., 3700 years B.P., 2700 years B.P., 1300 years B.P. and 200 years B.P. and represented temperature drops.

References

{{Global warming History of climate variability and change Atlantic Ocean

List

Influence in regional climate

See also

References