Author
Ignacio A. Mundo
Other affiliations: National University of La Plata, National University of Cuyo, Facultad de Ciencias Exactas y Naturales
Bio: Ignacio A. Mundo is an academic researcher from National Scientific and Technical Research Council. The author has contributed to research in topics: Araucaria araucana & Austrocedrus. The author has an hindex of 17, co-authored 28 publications receiving 1866 citations. Previous affiliations of Ignacio A. Mundo include National University of La Plata & National University of Cuyo.
Papers
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Federal Urdu University1, Columbia University2, Woods Hole Oceanographic Institution3, Addis Ababa University4, Indian Institute of Tropical Meteorology5, University of Trieste6, Swiss Federal Institute for Forest, Snow and Landscape Research7, University of Bergen8, University of Montpellier9, Austral University of Chile10, University of Chile11, Australian Antarctic Division12, University of Tasmania13, National Oceanic and Atmospheric Administration14, University of Mainz15, Xishuangbanna Tropical Botanical Garden16, Nepal Academy of Science and Technology17, Chinese Academy of Sciences18, University of Melbourne19, Complutense University of Madrid20, Université catholique de Louvain21, University of the Witwatersrand22, Hydrologic Research Center23, University of Bern24, University of Helsinki25, Northern Arizona University26, Fukushima University27, Stockholm University28, Université Paris-Saclay29, National Institute of Water and Atmospheric Research30, University of Giessen31, Swansea University32, Desert Research Institute33, National Scientific and Technical Research Council34, British Antarctic Survey35, Nagoya University36, University of Brighton37, Florida State University38, Alfred Wegener Institute for Polar and Marine Research39, University of Exeter40, University of New South Wales41, Centro de Estudios Científicos42, University of Florence43, University of Texas at Austin44, Russian Academy of Sciences45, University of Washington46, National Centre for Antarctic and Ocean Research47, University of Arizona48, Ghent University49, University of Ottawa50, University of Copenhagen51, University of Colorado Boulder52, Shinshu University53
TL;DR: The authors reconstructed past temperatures for seven continental-scale regions during the past one to two millennia and found that the most coherent feature in nearly all of the regional temperature reconstructions is a long-term cooling trend, which ended late in the nineteenth century.
Abstract: Past global climate changes had strong regional expression To elucidate their spatio-temporal pattern, we reconstructed past temperatures for seven continental-scale regions during the past one to two millennia The most coherent feature in nearly all of the regional temperature reconstructions is a long-term cooling trend, which ended late in the nineteenth century At multi-decadal to centennial scales, temperature variability shows distinctly different regional patterns, with more similarity within each hemisphere than between them There were no globally synchronous multi-decadal warm or cold intervals that define a worldwide Medieval Warm Period or Little Ice Age, but all reconstructions show generally cold conditions between ad 1580 and 1880, punctuated in some regions by warm decades during the eighteenth century The transition to these colder conditions occurred earlier in the Arctic, Europe and Asia than in North America or the Southern Hemisphere regions Recent warming reversed the long-term cooling; during the period ad 1971–2000, the area-weighted average reconstructed temperature was higher than any other time in nearly 1,400 years
885 citations
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University of Southern California1, Northern Arizona University2, MathWorks3, University of Arizona4, Australian National University5, United States Geological Survey6, Australian Antarctic Division7, University of Tasmania8, University of Maryland, College Park9, University of Melbourne10, Spanish National Research Council11, University of Cambridge12, University of Wollongong13, University of Bern14, Ca' Foscari University of Venice15, University of Texas at Austin16, University of Bergen17, Chinese Academy of Sciences18, Norwegian Polar Institute19, National University of Cuyo20, University of Washington21, University of Adelaide22, Victoria University of Wellington23, Swiss Federal Institute for Forest, Snow and Landscape Research24, University of Montpellier25, National Taiwan Ocean University26, Columbia University27, Louisiana State University28, University of Maine29, Arctic and Antarctic Research Institute30, Saint Petersburg State University31, Northumbria University32, Lund University33, Institut national de la recherche scientifique34, Nepal Academy of Science and Technology35, Tribhuvan University36, University of Ottawa37, Université catholique de Louvain38, Hirosaki University39, University of Gothenburg40, Xiamen University41, National Institute of Polar Research42, Japan Agency for Marine-Earth Science and Technology43, Aix-Marseille University44, National Institute of Water and Atmospheric Research45, Russian Academy of Sciences46, Autonomous University of Barcelona47, British Antarctic Survey48, University of Tübingen49, University of Brighton50, University of the Witwatersrand51, Alfred Wegener Institute for Polar and Marine Research52, Université Paris-Saclay53, Sukachev Institute of Forest54, University of Toronto55, University at Buffalo56, Australian Nuclear Science and Technology Organisation57, Aarhus University58, University of Florence59, Pierre-and-Marie-Curie University60, Paul Scherrer Institute61, University of Minnesota62, University of Regina63, Concordia University64, National Centre for Antarctic and Ocean Research65, University of New South Wales66, University of the Ryukyus67, National Oceanic and Atmospheric Administration68, University of Colorado Boulder69, Lehigh University70, Australian Institute of Marine Science71, Free University of Berlin72
TL;DR: A community-sourced database of temperature-sensitive proxy records from the PAGES2k initiative, suited to investigations of global and regional temperature variability over the Common Era, and is shared in the Linked Paleo Data (LiPD) format, including serializations in Matlab, R and Python.
Abstract: Reproducible climate reconstructions of the Common Era (1 CE to present) are key to placing industrial-era warming into the context of natural climatic variability. Here we present a community-sourced database of temperature-sensitive proxy records from the PAGES2k initiative. The database gathers 692 records from 648 locations, including all continental regions and major ocean basins. The records are from trees, ice, sediment, corals, speleothems, documentary evidence, and other archives. They range in length from 50 to 2000 years, with a median of 547 years, while temporal resolution ranges from biweekly to centennial. Nearly half of the proxy time series are significantly correlated with HadCRUT4.2 surface temperature over the period 1850–2014. Global temperature composites show a remarkable degree of coherence between high- and low-resolution archives, with broadly similar patterns across archive types, terrestrial versus marine locations, and screening criteria. The database is suited to investigations of global and regional temperature variability over the Common Era, and is shared in the Linked Paleo Data (LiPD) format, including serializations in Matlab, R and Python.
260 citations
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Oeschger Centre for Climate Change Research1, University of Zurich2, University of Melbourne3, Cooperative Research Centre4, Australian Antarctic Division5, Complutense University of Madrid6, Lamont–Doherty Earth Observatory7, National University of La Plata8, National Scientific and Technical Research Council9, University of Bern10, University of Washington11, Australian Institute of Marine Science12, University of Western Australia13
TL;DR: In this article, a new millennial ensemble reconstruction of annually resolved temperature variations for the Southern Hemisphere based on an unprecedented network of terrestrial and oceanic palaeoclimate proxy records is presented.
Abstract: The Earth’s climate system is driven by a complex interplay of internal chaotic dynamics and natural and anthropogenic external forcing. Recent instrumental data have shown a remarkable degree of asynchronicity between Northern Hemisphere and Southern Hemisphere temperature fluctuations, thereby questioning the relative importance of internal versus external drivers of past as well as future climate variability1, 2, 3. However, large-scale temperature reconstructions for the past millennium have focused on the Northern Hemisphere4, 5, limiting empirical assessments of inter-hemispheric variability on multi-decadal to centennial timescales. Here, we introduce a new millennial ensemble reconstruction of annually resolved temperature variations for the Southern Hemisphere based on an unprecedented network of terrestrial and oceanic palaeoclimate proxy records. In conjunction with an independent Northern Hemisphere temperature reconstruction ensemble5, this record reveals an extended cold period (1594–1677) in both hemispheres but no globally coherent warm phase during the pre-industrial (1000–1850) era. The current (post-1974) warm phase is the only period of the past millennium where both hemispheres are likely to have experienced contemporaneous warm extremes. Our analysis of inter-hemispheric temperature variability in an ensemble of climate model simulations for the past millennium suggests that models tend to overemphasize Northern Hemisphere–Southern Hemisphere synchronicity by underestimating the role of internal ocean–atmosphere dynamics, particularly in the ocean-dominated Southern Hemisphere. Our results imply that climate system predictability on decadal to century timescales may be lower than expected based on assessments of external climate forcing and Northern Hemisphere temperature variations5, 6 alone.
236 citations
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TL;DR: In this article, the authors used tree-ring records from over 3,000 trees in South America, Tasmania and New Zealand to identify dominant patterns of tree growth in recent centuries and showed that the foremost patterns of growth between 1950 and 2000 differed significantly from those in the previous 250 years.
Abstract: Recent changes in the summer climate of the Southern Hemisphere extra-tropics are primarily related to the dominance of the positive phase of the Southern Annular Mode1, 2 This shift in the behaviour of the Southern Annular Mode—essentially a measure of the pressure gradient between Southern Hemisphere mid and high latitudes—has been predominantly induced by polar stratospheric ozone depletion2, 3, 4 The concomitant southward expansion of the dry subtropical belts5, 6 could have consequences for forest growth Here, we use tree-ring records from over 3,000 trees in South America, Tasmania and New Zealand to identify dominant patterns of tree growth in recent centuries We show that the foremost patterns of growth between 1950 and 2000 differed significantly from those in the previous 250 years Specifically, growth was higher than the long-term average in the subalpine forests of Tasmania and New Zealand, but lower in the dry-mesic forests of Patagonia We further demonstrate that variations in the Southern Annular Mode can explain 12–48% of the tree growth anomalies in the latter half of the twentieth century Tree-ring-based reconstructions of summer Southern Annular Mode indices suggest that the high frequency of the positive phase since the 1950s is unprecedented in the past 600 years We propose that changes in the Southern Annular Mode have significantly altered tree growth patterns in the Southern Hemisphere
215 citations
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Lamont–Doherty Earth Observatory1, Versailles Saint-Quentin-en-Yvelines University2, Austral University of Chile3, National Scientific and Technical Research Council4, Universidad Mayor5, University of Toulouse6, Russian Academy of Sciences7, University of Magallanes8, National University of Cuyo9, National University of Río Negro10, Columbia University11, Pontifical Catholic University of Valparaíso12, University of Western Ontario13, University of East Anglia14, National University of Jujuy15
TL;DR: The South American Drought Atlas provides a long-term context for observed hydroclimatic changes and for 21st-century Intergovernmental Panel on Climate Change (IPCC) projections that suggest SA will experience more frequent/severe droughts and rainfall events as a consequence of increasing greenhouse gas emissions.
Abstract: South American (SA) societies are highly vulnerable to droughts and pluvials, but lack of long-term climate observations severely limits our understanding of the global processes driving climatic variability in the region. The number and quality of SA climate-sensitive tree ring chronologies have significantly increased in recent decades, now providing a robust network of 286 records for characterizing hydroclimate variability since 1400 CE. We combine this network with a self-calibrated Palmer Drought Severity Index (scPDSI) dataset to derive the South American Drought Atlas (SADA) over the continent south of 12°S. The gridded annual reconstruction of austral summer scPDSI is the most spatially complete estimate of SA hydroclimate to date, and well matches past historical dry/wet events. Relating the SADA to the Australia-New Zealand Drought Atlas, sea surface temperatures and atmospheric pressure fields, we determine that the El Nino-Southern Oscillation (ENSO) and the Southern Annular Mode (SAM) are strongly associated with spatially extended droughts and pluvials over the SADA domain during the past several centuries. SADA also exhibits more extended severe droughts and extreme pluvials since the mid-20th century. Extensive droughts are consistent with the observed 20th-century trend toward positive SAM anomalies concomitant with the weakening of midlatitude Westerlies, while low-level moisture transport intensified by global warming has favored extreme rainfall across the subtropics. The SADA thus provides a long-term context for observed hydroclimatic changes and for 21st-century Intergovernmental Panel on Climate Change (IPCC) projections that suggest SA will experience more frequent/severe droughts and rainfall events as a consequence of increasing greenhouse gas emissions.
107 citations
Cited by
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TL;DR: The authors reviewed the historical genesis of the Anthropocene Epoch idea and assessed anthropogenic signatures in the geological record against the formal requirements for the recognition of a new epoch, finding that of the various proposed dates two do appear to conform to the criteria to mark the beginning of the anthropocene: 1610 and 1964.
Abstract: Time is divided by geologists according to marked shifts in Earth's state. Recent global environmental changes suggest that Earth may have entered a new human-dominated geological epoch, the Anthropocene. Here we review the historical genesis of the idea and assess anthropogenic signatures in the geological record against the formal requirements for the recognition of a new epoch. The evidence suggests that of the various proposed dates two do appear to conform to the criteria to mark the beginning of the Anthropocene: 1610 and 1964. The formal establishment of an Anthropocene Epoch would mark a fundamental change in the relationship between humans and the Earth system.
1,578 citations
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British Geological Survey1, University of Leicester2, Scott Polar Research Institute3, University of California, Berkeley4, Centre national de la recherche scientifique5, Jan Kochanowski University6, University of the Basque Country7, University of Maryland, Baltimore County8, Institut de recherche pour le développement9, Free University of Berlin10, Georgetown University11, Duke University12, Australian National University13, University of Colorado Boulder14, Fridtjof Nansen Institute15, University of Vienna16, Chinese Academy of Sciences17, Graduate Institute of International and Development Studies18, University of Nairobi19, Harvard University20, University of Alberta21
TL;DR: C climatic, biological, and geochemical signatures of human activity in sediments and ice cores, Combined with deposits of new materials and radionuclides, as well as human-caused modification of sedimentary processes, the Anthropocene stands alone stratigraphically as a new epoch beginning sometime in the mid–20th century.
Abstract: Human activity is leaving a pervasive and persistent signature on Earth. Vigorous debate continues about whether this warrants recognition as a new geologic time unit known as the Anthropocene. We review anthropogenic markers of functional changes in the Earth system through the stratigraphic record. The appearance of manufactured materials in sediments, including aluminum, plastics, and concrete, coincides with global spikes in fallout radionuclides and particulates from fossil fuel combustion. Carbon, nitrogen, and phosphorus cycles have been substantially modified over the past century. Rates of sea-level rise and the extent of human perturbation of the climate system exceed Late Holocene changes. Biotic changes include species invasions worldwide and accelerating rates of extinction. These combined signals render the Anthropocene stratigraphically distinct from the Holocene and earlier epochs.
1,441 citations
01 Apr 2016
TL;DR: The evidence suggests that of the various proposed dates two do appear to conform to the criteria to mark the beginning of the Anthropocene: 1610 and 1964.
Abstract: Time is divided by geologists according to marked shifts in Earth's state. Recent global environmental changes suggest that Earth may have entered a new human-dominated geological epoch, the Anthropocene. Here we review the historical genesis of the idea and assess anthropogenic signatures in the geological record against the formal requirements for the recognition of a new epoch. The evidence suggests that of the various proposed dates two do appear to conform to the criteria to mark the beginning of the Anthropocene: 1610 and 1964. The formal establishment of an Anthropocene Epoch would mark a fundamental change in the relationship between humans and the Earth system.
1,173 citations
01 Jan 1981
TL;DR: It is suggested that the reproductive season of certain long—lived, patch—dependent species is moulded by the disturbance regime, and the necessary and vital connection between disturbance which generates spatial pattern and species richness in communities open to invasion is discussed.
Abstract: The mussel Mytilus californianus is a competitive dominant on wave—swept rocky intertidal shores. Mussel beds may exist as extensive monocultures; more often they are an everchanging mosaic of many species which inhabit wave—generated patches or gaps. This paper describes observations and experiments designed to measure the critical parameters of a model of patch birth and death, and to use the model to predict the spatial structure of mussel beds. Most measurements were made at Tatoosh Island, Washington, USA, from 1970—1979. Patch size ranged at birth from a single mussel to 38 m2; the distribution of patch sizes approximates the lognormal. Birth rates varied seasonally and regionally. At Tatoosh the rate of patch formation varied during six winters from 0.4—5.4% of the mussels removed per month. The disturbance regime during the summer and at two mainland sites was 5—10 times less. Annual disturbance patterns tended to be synchronous within 11 sites on one face of Tatoosh over a 10—yr interval, and over larger distances (16 km) along the coastline. The pattern was asynchronous, however, among four Tatoosh localities. Patch birth rate, and mean and maximum size at birth can be used as adequate indices of disturbance. Patch disappearance (death) occurs by three mechanisms. Very small patches disappear almost immediately due to a leaning response of the border mussels (0.2 cm/d). Intermediate—sized patches (<3.0 m2) are eventually obliterated by lateral movement of the peripheral mussels: estimates based on 94 experimental patches yield a mean shrinking rate of 0.05 cm/d from each of two principal dimensions. Depth of the adjacent mussel bed accounts for much of the local variation in closing rate. In very large patches, mussels must recruit as larvae from the plankton. Recovery begins at an average patch age of 26 mo; rate of space occupation, primarily due to individual growth, is 2.0—2.5%/mo. Winter birth rates suggest a mean turnover time (rotation period) for mussel beds varying from 8.1—34.7 yr, depending on the location. The minimal value is in close agreement with both observed and calculated minimal recovery times. Projections of total patch area, based on the model, are accurate to within 5% of the observed. Using a method for determining the age of patches, based on a growth curve of the barnacle Balanus cariosus, the model permits predictions of the age—size structure of the patch population. The model predicts with excellent resolution the distribution of patch area in relation to time since last disturbance. The most detailed models which include size structure within age categories are inconclusive due to small sample size. Predictions are food for large patches, the major determinants of environmental patterns, but cannot deal adequately with smaller patches because of stochastic effects. Colonization data are given in relation to patch age, size and intertidal position. We suggest that the reproductive season of certain long—lived, patch—dependent species is moulded by the disturbance regime. The necessary and vital connection between disturbance which generates spatial pattern and species richness in communities open to invasion is discussed.
1,082 citations
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Nevada System of Higher Education1, University of Washington2, University of California, Berkeley3, Queen's University Belfast4, Energy Institute5, Oeschger Centre for Climate Change Research6, Purdue University7, University of Copenhagen8, Alfred Wegener Institute for Polar and Marine Research9, University of Nottingham10, Lund University11, Natural Environment Research Council12, University of Arizona13
TL;DR: It is shown that large eruptions in the tropics and high latitudes were primary drivers of interannual-to-decadal temperature variability in the Northern Hemisphere during the past 2,500 years and cooling was proportional to the magnitude of volcanic forcing.
Abstract: Volcanic eruptions contribute to climate variability, but quantifying these contributions has been limited by inconsistencies in the timing of atmospheric volcanic aerosol loading determined from ice cores and subsequent cooling from climate proxies such as tree rings. Here we resolve these inconsistencies and show that large eruptions in the tropics and high latitudes were primary drivers of interannual-to-decadal temperature variability in the Northern Hemisphere during the past 2,500 years. Our results are based on new records of atmospheric aerosol loading developed from high-resolution, multi-parameter measurements from an array of Greenland and Antarctic ice cores as well as distinctive age markers to constrain chronologies. Overall, cooling was proportional to the magnitude of volcanic forcing and persisted for up to ten years after some of the largest eruptive episodes. Our revised timescale more firmly implicates volcanic eruptions as catalysts in the major sixth-century pandemics, famines, and socioeconomic disruptions in Eurasia and Mesoamerica while allowing multi-millennium quantification of climate response to volcanic forcing.
841 citations