Author
Hans W. Linderholm
Other affiliations: Stockholm University, University of Cambridge, Chinese Academy of Sciences ...read more
Bio: Hans W. Linderholm is an academic researcher from University of Gothenburg. The author has contributed to research in topics: Climate change & Scots pine. The author has an hindex of 44, co-authored 158 publications receiving 7213 citations. Previous affiliations of Hans W. Linderholm include Stockholm University & University of Cambridge.
Papers published on a yearly basis
Papers
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TL;DR: In this paper, the first empirical orthogonal function (EOF) of observed summertime extratropical North Atlantic pressure at mean sea level is defined, which is characterized by a more northerly location and smaller spatial scale than its winter counterpart.
Abstract: Summer climate in the North Atlantic‐European sector possesses a principal pattern of year-to-year variability that is the parallel to the well-known North Atlantic Oscillation in winter. This summer North Atlantic Oscillation (SNAO) is defined here as the first empirical orthogonal function (EOF) of observed summertime extratropical North Atlantic pressure at mean sea level. It is shown to be characterized by a more northerly location and smaller spatial scale than its winter counterpart. The SNAO is also detected by cluster analysis and has a near-equivalent barotropic structure on daily and monthly time scales. Although of lesser amplitude than its wintertime counterpart, the SNAO exerts a strong influence on northern European rainfall, temperature, and cloudiness through changes in the position of the North Atlantic storm track. It is, therefore, of key importance in generating summer climate extremes, including flooding, drought, and heat
638 citations
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TL;DR: Changes in the timing and length of the growing season may not only have far reaching consequences for plant and animal ecosystems, but persistent increases in GSL may lead to long-term increases in carbon storage and changes in vegetation cover which may affect the climate system.
578 citations
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Lamont–Doherty Earth Observatory1, University of East Anglia2, University of Freiburg3, Royal Netherlands Meteorological Institute4, Queen's University Belfast5, University of Padua6, University of Ljubljana7, University of Mainz8, Cornell University9, Stockholm University10, Dresden University of Technology11, University of Barcelona12, United States Department of State13, Deutsches Archäologisches Institut14, Czech University of Life Sciences Prague15, Istanbul University16, University of Gothenburg17, University of Oxford18, University of Pavia19, University of Forestry, Sofia20, Norwegian University of Science and Technology21, University of Arizona22, Nicolaus Copernicus University in Toruń23, University of St Andrews24, Technische Universität München25
TL;DR: Megadroughts reconstructed over north-central Europe in the 11th and mid-15th centuries reinforce other evidence from North America and Asia that droughts were more severe, extensive, and prolonged over Northern Hemisphere land areas before the 20th century, with an inadequate understanding of their causes.
Abstract: Climate model projections suggest widespread drying in the Mediterranean Basin and wetting in Fennoscandia in the coming decades largely as a consequence of greenhouse gas forcing of climate. To place these and other “Old World” climate projections into historical perspective based on more complete estimates of natural hydroclimatic variability, we have developed the “Old World Drought Atlas” (OWDA), a set of year-to-year maps of tree-ring reconstructed summer wetness and dryness over Europe and the Mediterranean Basin during the Common Era. The OWDA matches historical accounts of severe drought and wetness with a spatial completeness not previously available. In addition, megadroughts reconstructed over north-central Europe in the 11th and mid-15th centuries reinforce other evidence from North America and Asia that droughts were more severe, extensive, and prolonged over Northern Hemisphere land areas before the 20th century, with an inadequate understanding of their causes. The OWDA provides new data to determine the causes of Old World drought and wetness and attribute past climate variability to forced and/or internal variability.
429 citations
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Massachusetts Institute of Technology1, University of Alaska Fairbanks2, Woods Hole Oceanographic Institution3, Alfred Wegener Institute for Polar and Marine Research4, University of Bremen5, California Institute of Technology6, National Oceanic and Atmospheric Administration7, Texas State University8, Pennsylvania State University9, Lund University10, VU University Amsterdam11, Potsdam Institute for Climate Impact Research12, Utah State University13, United States Naval Academy14, Environment Canada15, University of Gothenburg16, University of Cambridge17, Naval Postgraduate School18, University of California, Irvine19, University of Washington20, University College London21, Langley Research Center22, University of Wisconsin-Madison23, Finnish Meteorological Institute24, Leipzig University25, Columbia University26, Gwangju Institute of Science and Technology27
TL;DR: The Arctic has warmed more than twice as fast as the global average since the late twentieth century, a phenomenon known as Arctic amplification (AA), and progress has been made in understanding the mechanisms that link it to midlatitude weather variability as discussed by the authors.
Abstract: The Arctic has warmed more than twice as fast as the global average since the late twentieth century, a phenomenon known as Arctic amplification (AA). Recently, there have been considerable advances in understanding the physical contributions to AA, and progress has been made in understanding the mechanisms that link it to midlatitude weather variability. Observational studies overwhelmingly support that AA is contributing to winter continental cooling. Although some model experiments support the observational evidence, most modelling results show little connection between AA and severe midlatitude weather or suggest the export of excess heating from the Arctic to lower latitudes. Divergent conclusions between model and observational studies, and even intramodel studies, continue to obfuscate a clear understanding of how AA is influencing midlatitude weather.
423 citations
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Stockholm University1, University of East Anglia2, University of Gothenburg3, University of Augsburg4, Met Office5, University of Bern6, French Alternative Energies and Atomic Energy Commission7, Royal Netherlands Meteorological Institute8, Swedish Meteorological and Hydrological Institute9, Central Institution for Meteorology and Geodynamics10, University of Barcelona11, MeteoSwiss12, Uppsala University13, Armagh Observatory14, Finnish Meteorological Institute15, Potsdam Institute for Climate Impact Research16, University of Milan17, Czech Hydrometeorological Institute18
TL;DR: In this paper, the authors analyzed century-long daily temperature and precipitation records for stations in Europe west of 60°E and defined a set of climatic indices derived from the daily series, mainly focusing on extremes.
Abstract: [1] We analyze century-long daily temperature and precipitation records for stations in Europe west of 60°E. A set of climatic indices derived from the daily series, mainly focusing on extremes, is defined. Linear trends in these indices are assessed over the period 1901–2000. Average trends, for 75 stations mostly representing Europe west of 20°E, show a warming for all temperature indices. Winter has, on average, warmed more (∼1.0°C/100 yr) than summer (∼0.8°C), both for daily maximum (TX) and minimum (TN) temperatures. Overall, the warming of TX in winter was stronger in the warm tail than in the cold tail (1.6 and 1.5°C for 98th and 95th, but ∼1.0°C for 2nd, 5th and 10th percentiles). There are, however, large regional differences in temperature trend patterns. For summer, there is a tendency for stronger warming, both for TX and TN, in the warm than in the cold tail only in parts of central Europe. Winter precipitation totals, averaged over 121 European stations north of 40°N, have increased significantly by ∼12% per 100 years. Trends in 90th, 95th and 98th percentiles of daily winter precipitation have been similar. No overall long-term trend occurred in summer precipitation totals, but there is an overall weak (statistically insignificant and regionally dependent) tendency for summer precipitation to have become slightly more intense but less common. Data inhomogeneities and relative sparseness of station density in many parts of Europe preclude more robust conclusions. It is of importance that new methods are developed for homogenizing daily data.
410 citations
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TL;DR: In this article, the authors present a document, redatto, voted and pubblicato by the Ipcc -Comitato intergovernativo sui cambiamenti climatici - illustra la sintesi delle ricerche svolte su questo tema rilevante.
Abstract: Cause, conseguenze e strategie di mitigazione Proponiamo il primo di una serie di articoli in cui affronteremo l’attuale problema dei mutamenti climatici. Presentiamo il documento redatto, votato e pubblicato dall’Ipcc - Comitato intergovernativo sui cambiamenti climatici - che illustra la sintesi delle ricerche svolte su questo tema rilevante.
4,187 citations
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Queen's University Belfast1, University of St Andrews2, Aix-Marseille University3, Historic England4, University of Sheffield5, University of Oxford6, Alfred Wegener Institute for Polar and Marine Research7, Xi'an Jiaotong University8, University of Minnesota9, Nanjing Normal University10, University of Hohenheim11, University of Kiel12, University of California, Santa Cruz13, Lawrence Livermore National Laboratory14, ETH Zurich15, University of Waikato16, Woods Hole Oceanographic Institution17, Heidelberg University18, Cornell University19, Lund University20, University of New South Wales21, University of Arizona22, University of Groningen23, University of Bristol24, University of Glasgow25, University of California, Irvine26, University of Bern27, Aarhus University28, Nagoya University29, Swiss Federal Institute for Forest, Snow and Landscape Research30, National Museum of Japanese History31, University of Bologna32
TL;DR: In this article, the international 14C calibration curves for both the Northern and Southern Hemispheres, as well as for the ocean surface layer, have been updated to include a wealth of new data and extended to 55,000 cal BP.
Abstract: Radiocarbon (14C) ages cannot provide absolutely dated chronologies for archaeological or paleoenvironmental studies directly but must be converted to calendar age equivalents using a calibration curve compensating for fluctuations in atmospheric 14C concentration. Although calibration curves are constructed from independently dated archives, they invariably require revision as new data become available and our understanding of the Earth system improves. In this volume the international 14C calibration curves for both the Northern and Southern Hemispheres, as well as for the ocean surface layer, have been updated to include a wealth of new data and extended to 55,000 cal BP. Based on tree rings, IntCal20 now extends as a fully atmospheric record to ca. 13,900 cal BP. For the older part of the timescale, IntCal20 comprises statistically integrated evidence from floating tree-ring chronologies, lacustrine and marine sediments, speleothems, and corals. We utilized improved evaluation of the timescales and location variable 14C offsets from the atmosphere (reservoir age, dead carbon fraction) for each dataset. New statistical methods have refined the structure of the calibration curves while maintaining a robust treatment of uncertainties in the 14C ages, the calendar ages and other corrections. The inclusion of modeled marine reservoir ages derived from a three-dimensional ocean circulation model has allowed us to apply more appropriate reservoir corrections to the marine 14C data rather than the previous use of constant regional offsets from the atmosphere. Here we provide an overview of the new and revised datasets and the associated methods used for the construction of the IntCal20 curve and explore potential regional offsets for tree-ring data. We discuss the main differences with respect to the previous calibration curve, IntCal13, and some of the implications for archaeology and geosciences ranging from the recent past to the time of the extinction of the Neanderthals.
2,800 citations
01 Dec 2010
TL;DR: In this article, the authors suggest a reduction in the global NPP of 0.55 petagrams of carbon, which would not only weaken the terrestrial carbon sink, but would also intensify future competition between food demand and biofuel production.
Abstract: Terrestrial net primary production (NPP) quantifies the amount of atmospheric carbon fixed by plants and accumulated as biomass. Previous studies have shown that climate constraints were relaxing with increasing temperature and solar radiation, allowing an upward trend in NPP from 1982 through 1999. The past decade (2000 to 2009) has been the warmest since instrumental measurements began, which could imply continued increases in NPP; however, our estimates suggest a reduction in the global NPP of 0.55 petagrams of carbon. Large-scale droughts have reduced regional NPP, and a drying trend in the Southern Hemisphere has decreased NPP in that area, counteracting the increased NPP over the Northern Hemisphere. A continued decline in NPP would not only weaken the terrestrial carbon sink, but it would also intensify future competition between food demand and proposed biofuel production.
1,780 citations
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University of Massachusetts Amherst1, National Oceanic and Atmospheric Administration2, Université du Québec à Montréal3, Newcastle University4, University of Bern5, Chinese Academy of Sciences6, Rutgers University7, École Polytechnique Fédérale de Lausanne8, University of Graz9, University of Reading10, Shanxi University11, University of Alberta12, Environment Canada13
TL;DR: In this paper, the authors review important mechanisms that contribute towards elevation-dependent warming, such as snow albedo and surface-based feedbacks, water vapour changes and latent heat release, surface water vapours and radiative flux changes, surface heat loss and temperature change; and aerosols.
Abstract: There is growing evidence that the rate of warming is amplified with elevation, such that high-mountain environments experience more rapid changes in temperature than environments at lower elevations. Elevation-dependent warming (EDW) can accelerate the rate of change in mountain ecosystems, cryospheric systems, hydrological regimes and biodiversity. Here we review important mechanisms that contribute towards EDW: snow albedo and surface-based feedbacks; water vapour changes and latent heat release; surface water vapour and radiative flux changes; surface heat loss and temperature change; and aerosols. All lead to enhanced warming with elevation (or at a critical elevation), and it is believed that combinations of these mechanisms may account for contrasting regional patterns of EDW. We discuss future needs to increase knowledge of mountain temperature trends and their controlling mechanisms through improved observations, satellite-based remote sensing and model simulations.
1,628 citations
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TL;DR: In this paper, the authors discuss the environmental drivers of phenology, and the impacts of climate change on phenology in different biomes, and assess the potential impact on these feedbacks of shifts in phenology driven by climate change.
1,522 citations