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Gerald H. Haug

Bio: Gerald H. Haug is an academic researcher from Max Planck Society. The author has contributed to research in topics: Glacial period & Holocene. The author has an hindex of 60, co-authored 184 publications receiving 17516 citations. Previous affiliations of Gerald H. Haug include ETH Zurich & Woods Hole Oceanographic Institution.


Papers
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Journal ArticleDOI
17 Aug 2001-Science
TL;DR: The Cariaco Basin record exhibits strong correlations with climate records from distant regions, including the high-latitude Northern Hemisphere, providing evidence for global teleconnections among regional climates.
Abstract: Titanium and iron concentration data from the anoxic Cariaco Basin, off the Venezuelan coast, can be used to infer variations in the hydrological cycle over northern South America during the past 14,000 years with subdecadal resolution. Following a dry Younger Dryas, a period of increased precipitation and riverine discharge occurred during the Holocene “thermal maximum.” Since ∼5400 years ago, a trend toward drier conditions is evident from the data, with high-amplitude fluctuations and precipitation minima during the time interval 3800 to 2800 years ago and during the “Little Ice Age.” These regional changes in precipitation are best explained by shifts in the mean latitude of the Atlantic Intertropical Convergence Zone (ITCZ), potentially driven by Pacific-based climate variability. The Cariaco Basin record exhibits strong correlations with climate records from distant regions, including the high-latitude Northern Hemisphere, providing evidence for global teleconnections among regional climates.

2,032 citations

Journal ArticleDOI
04 Sep 2014-Nature
TL;DR: An emerging framework links the intertropical convergence zone to the atmospheric energy balance and may account for ITCZ variations on timescales from years to geological epochs.
Abstract: Rainfall on Earth is most intense in the intertropical convergence zone (ITCZ), a narrow belt of clouds centred on average around six degrees north of the Equator. The mean position of the ITCZ north of the Equator arises primarily because the Atlantic Ocean transports energy northward across the Equator, rendering the Northern Hemisphere warmer than the Southern Hemisphere. On seasonal and longer timescales, the ITCZ migrates, typically towards a warming hemisphere but with exceptions, such as during El Nino events. An emerging framework links the ITCZ to the atmospheric energy balance and may account for ITCZ variations on timescales from years to geological epochs.

930 citations

Journal ArticleDOI
08 Dec 2000-Science
TL;DR: Sedimentary time series of color reflectance and major element chemistry from the anoxic Cariaco Basin off the coast of northern Venezuela record large and abrupt shifts in the hydrologic cycle of the tropical Atlantic during the past 90,000 years, which supports the notion that tropical feedbacks played an important role in modulating global climate during the last glacial period.
Abstract: Sedimentary time series of color reflectance and major element chemistry from the anoxic Cariaco Basin off the coast of northern Venezuela record large and abrupt shifts in the hydrologic cycle of the tropical Atlantic during the past 90,000 years. Marine productivity maxima and increased precipitation and riverine discharge from northern South America are closely linked to interstadial (warm) climate events of marine isotope stage 3, as recorded in Greenland ice cores. Increased precipitation at this latitude during interstadials suggests the potential for greater moisture export from the Atlantic to Pacific, which could have affected the salinity balance of the Atlantic and increased thermohaline heat transport to high northern latitudes. This supports the notion that tropical feedbacks played an important role in modulating global climate during the last glacial period.

890 citations

Journal ArticleDOI
01 Jan 1998-Nature
TL;DR: In this paper, stable-isotope and carbonate sand-fraction records from Caribbean sediments were used to investigate the timing and consequences of the emergence of the Isthmus of Panama, which closed the seaway between the North andSouth American continents.
Abstract: The Late Cenozoic closure of the seaway between the North andSouth American continents is thought to have caused extensive changes in ocean circulation and Northern Hemisphere climate1,2 But the timing and consequences of the emergence of the Isthmus of Panama, which closed the seaway, remain controversial1,2,3,4,5 Here we present stable-isotope and carbonate sand-fraction records from Caribbean sediments which, when compared to Atlantic and Pacific palaeoceanographic records, indicate that the closure caused a marked reorganization of ocean circulation starting 46 million years ago Shallowing of the seaway intensified the Gulf Stream and introduced warm and saline water masses to high northern latitudes These changes strengthened deep-water formation in the Labrador Sea over the next million years — as indicated by an increased deep-water ventilation and carbonate preservation in the Caribbean Sea — and favoured early Pliocene warming of the Northern Hemisphere The evaporative cooling of surface waters during North Atlantic Deep Water formation would have introduced moisture to the Northern Hemisphere Although the pronounced intensification of Northern Hemisphere glaciation between 31 and 25 million years ago substantially lagged the full development of North Atlantic Deep Water formation, we propose that the increased atmospheric moisture content was a necessary precondition for ice-sheet growth, which was then triggered by the incremental changes in the Earth's orbital obliquity

882 citations

Journal ArticleDOI
04 Jan 2007-Nature
TL;DR: High-resolution records of the magnetic properties and the titanium content of the sediments of Lake Huguang Maar in coastal southeast China over the past 16,000 years are presented, using as proxies for the strength of the winter monsoon winds, to suggest that these migrations in the tropical rain belt could have contributed to the declines of both the Tang dynasty in China and the Classic Maya in Central America.
Abstract: A palaeoclimate record spanning the past 16,000 years with nearly annual time resolution has been obtained from Lake Huguang Maar in China. The magnetic properties and titanium content of the lake sediments are thought to reflect changes in the East Asian winter monsoon strength, thus providing a complement to palaeoclimate archives that record the strength of the rain-bearing summer monsoon. The records point to an anti-correlation between winter and summer monsoon strength, best explained by migration of the intertropical convergence zone (ITCZ), a belt of low-pressure air at the Equator. Interestingly, the decline of China's Tang dynasty and the Mayan civilization broadly coincide with drought periods recorded in Lake Huguang Maar and Cariaco basin sediments, respectively. Did major shifts in the position of the ITCZ catalyse simultaneous events in civilizations on opposite sides of the Pacific Ocean? The Asian–Australian monsoon is an important component of the Earth’s climate system that influences the societal and economic activity of roughly half the world’s population. The past strength of the rain-bearing East Asian summer monsoon can be reconstructed with archives such as cave deposits1,2,3, but the winter monsoon has no such signature in the hydrological cycle and has thus proved difficult to reconstruct. Here we present high-resolution records of the magnetic properties and the titanium content of the sediments of Lake Huguang Maar in coastal southeast China over the past 16,000 years, which we use as proxies for the strength of the winter monsoon winds. We find evidence for stronger winter monsoon winds before the Bolling–Allerod warming, during the Younger Dryas episode and during the middle and late Holocene, when cave stalagmites suggest weaker summer monsoons1,2,3. We conclude that this anticorrelation is best explained by migrations in the intertropical convergence zone. Similar migrations of the intertropical convergence zone have been observed in Central America for the period ad 700 to 900 (refs 4–6), suggesting global climatic changes at that time. From the coincidence in timing, we suggest that these migrations in the tropical rain belt could have contributed to the declines of both the Tang dynasty in China and the Classic Maya in Central America.

810 citations


Cited by
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Journal ArticleDOI
27 Apr 2001-Science
TL;DR: This work focuses primarily on the periodic and anomalous components of variability over the early portion of this era, as constrained by the latest generation of deep-sea isotope records.
Abstract: Since 65 million years ago (Ma), Earth's climate has undergone a significant and complex evolution, the finer details of which are now coming to light through investigations of deep-sea sediment cores. This evolution includes gradual trends of warming and cooling driven by tectonic processes on time scales of 10(5) to 10(7) years, rhythmic or periodic cycles driven by orbital processes with 10(4)- to 10(6)-year cyclicity, and rare rapid aberrant shifts and extreme climate transients with durations of 10(3) to 10(5) years. Here, recent progress in defining the evolution of global climate over the Cenozoic Era is reviewed. We focus primarily on the periodic and anomalous components of variability over the early portion of this era, as constrained by the latest generation of deep-sea isotope records. We also consider how this improved perspective has led to the recognition of previously unforeseen mechanisms for altering climate.

8,903 citations

Journal ArticleDOI
13 Feb 2015-Science
TL;DR: An updated and extended analysis of the planetary boundary (PB) framework and identifies levels of anthropogenic perturbations below which the risk of destabilization of the Earth system (ES) is likely to remain low—a “safe operating space” for global societal development.
Abstract: The planetary boundaries framework defines a safe operating space for humanity based on the intrinsic biophysical processes that regulate the stability of the Earth system. Here, we revise and update the planetary boundary framework, with a focus on the underpinning biophysical science, based on targeted input from expert research communities and on more general scientific advances over the past 5 years. Several of the boundaries now have a two-tier approach, reflecting the importance of cross-scale interactions and the regional-level heterogeneity of the processes that underpin the boundaries. Two core boundaries—climate change and biosphere integrity—have been identified, each of which has the potential on its own to drive the Earth system into a new state should they be substantially and persistently transgressed.

7,169 citations

Journal ArticleDOI
TL;DR: In this paper, a 53-Myr stack (LR04) of benthic δ18O records from 57 globally distributed sites aligned by an automated graphic correlation algorithm is presented.
Abstract: [1] We present a 53-Myr stack (the “LR04” stack) of benthic δ18O records from 57 globally distributed sites aligned by an automated graphic correlation algorithm This is the first benthic δ18O stack composed of more than three records to extend beyond 850 ka, and we use its improved signal quality to identify 24 new marine isotope stages in the early Pliocene We also present a new LR04 age model for the Pliocene-Pleistocene derived from tuning the δ18O stack to a simple ice model based on 21 June insolation at 65°N Stacked sedimentation rates provide additional age model constraints to prevent overtuning Despite a conservative tuning strategy, the LR04 benthic stack exhibits significant coherency with insolation in the obliquity band throughout the entire 53 Myr and in the precession band for more than half of the record The LR04 stack contains significantly more variance in benthic δ18O than previously published stacks of the late Pleistocene as the result of higher-resolution records, a better alignment technique, and a greater percentage of records from the Atlantic Finally, the relative phases of the stack's 41- and 23-kyr components suggest that the precession component of δ18O from 27–16 Ma is primarily a deep-water temperature signal and that the phase of δ18O precession response changed suddenly at 16 Ma

6,186 citations

01 Jan 1980
TL;DR: In this article, the influence of diet on the distribution of nitrogen isotopes in animals was investigated by analyzing animals grown in the laboratory on diets of constant nitrogen isotopic composition and found that the variability of the relationship between the δ^(15)N values of animals and their diets is greater for different individuals raised on the same diet than for the same species raised on different diets.
Abstract: The influence of diet on the distribution of nitrogen isotopes in animals was investigated by analyzing animals grown in the laboratory on diets of constant nitrogen isotopic composition. The isotopic composition of the nitrogen in an animal reflects the nitrogen isotopic composition of its diet. The δ^(15)N values of the whole bodies of animals are usually more positive than those of their diets. Different individuals of a species raised on the same diet can have significantly different δ^(15)N values. The variability of the relationship between the δ^(15)N values of animals and their diets is greater for different species raised on the same diet than for the same species raised on different diets. Different tissues of mice are also enriched in ^(15)N relative to the diet, with the difference between the δ^(15)N values of a tissue and the diet depending on both the kind of tissue and the diet involved. The δ^(15)N values of collagen and chitin, biochemical components that are often preserved in fossil animal remains, are also related to the δ^(15)N value of the diet. The dependence of the δ^(15)N values of whole animals and their tissues and biochemical components on the δ^(15)N value of diet indicates that the isotopic composition of animal nitrogen can be used to obtain information about an animal's diet if its potential food sources had different δ^(15)N values. The nitrogen isotopic method of dietary analysis probably can be used to estimate the relative use of legumes vs non-legumes or of aquatic vs terrestrial organisms as food sources for extant and fossil animals. However, the method probably will not be applicable in those modern ecosystems in which the use of chemical fertilizers has influenced the distribution of nitrogen isotopes in food sources. The isotopic method of dietary analysis was used to reconstruct changes in the diet of the human population that occupied the Tehuacan Valley of Mexico over a 7000 yr span. Variations in the δ^(15)C and δ^(15)N values of bone collagen suggest that C_4 and/or CAM plants (presumably mostly corn) and legumes (presumably mostly beans) were introduced into the diet much earlier than suggested by conventional archaeological analysis.

5,548 citations