A5026995349- Geology and Paleoclimatology Research
- Isotope Analysis in Ecology
- Vietnamese History and Culture Studies
- Pleistocene-Era Hominins and Archaeology
- Archaeology and ancient environmental studies
- Geological formations and processes
- Urban and spatial planning
- Tree-ring climate responses
- Cambodian History and Society
- Geological and Geochemical Analysis
- earthquake and tectonic studies
- Methane Hydrates and Related Phenomena
- Archaeology and Historical Studies
- Geomagnetism and Paleomagnetism Studies
- Building materials and conservation
- Cultural Heritage Management and Preservation
- Southeast Asian Sociopolitical Studies
- Ancient Egypt and Archaeology
- Mobile Agent-Based Network Management
- Cultural Heritage Materials Analysis
- Maritime and Coastal Archaeology
- Asian Geopolitics and Ethnography
- Cryospheric studies and observations
- Lichen and fungal ecology
- Image Processing and 3D Reconstruction
Ritsumeikan University
2015-2024
Waseda University
2013-2023
National Museum of Nature and Science
2023
University of Newcastle Australia
2008-2022
Newcastle University
2008-2021
Siberian Branch of the Russian Academy of Sciences
2020
University of Tyumen
2020
East Japan Railway (Japan)
2005-2018
Meijo University
2009-2017
Meiji (India)
2017
Abstract The Greenland ice core from NorthGRIP (NGRIP) contains a proxy climate record across the Pleistocene–Holocene boundary of unprecedented clarity and resolution. Analysis an array physical chemical parameters within enables base Holocene, as reflected in first signs climatic warming at end Younger Dryas/Greenland Stadial 1 cold phase, to be located with high degree precision. This event is most clearly abrupt shift deuterium excess values, accompanied by more gradual changes δ 18 O,...
Dating Carbon Radiocarbon dating is the best way to determine age of samples that contain carbon and are younger than ∼50,000 years, limit precision for method. There several factors complicate such determinations, however, some most important which include variability 14 C production in atmosphere (which affects organic whose radiocarbon inventories derived from atmospheric CO 2 ), surface ocean reservoir effects affect marine acquire their signatures seawater), variable dead fraction...
Abstract Vegetation around the Daihai Lake, northern China, is very sensitive to climate changes. In this paper, pollen-based quantitative reconstructions using three methods [weighted averaging partial least squares method (WAPLS), modern analog technique (MAT), and pollen response surface (PRS)] were conducted obtain robust of Holocene changes in Lake area. The result obtained by all consistently show annual precipitation have been 50–100 mm lower early Holocene, 100–200 higher...
Pollen records from the annually laminated sediment sequence in Lake Suigetsu, Japan, suggest a of climate changes during Last Termination that resembles North Atlantic region but with noticeable differences timing. An interstadial interval commenced few centuries earlier [approximately 15,000 years before present (yr B.P.)] than GI-1 (Bölling) event. Conversely, onset Younger Dryas (YD)-like cold reversal (12,300 to 11,250 yr B.P.) postdated GS-1 (YD) event by centuries. Climate Far East...
Dense‐media separation, frequently adopted as a standard pollen extraction method for use with minerogenic sediment samples, was adapted organic‐rich and peat samples. A total of 15 obtained from sites in Corsica the Southern European Alps, treated using both dense‐media separation conventional preparation order to compare relative efficiencies two methods. The consistently achieved remarkably higher purity extracted grains. This especially true Corsican separations being quite pure, whereas...
Abstract Aim Our aims were to provide new pollen data for establishing a sub‐continental surface database (East Asian Pollen Database, EAPD) and study relationships between vegetation climate. Location The sample sites covered most regions of East Asia, including China, Mongolia, the Russian Far East, Vietnam, Cambodia Thailand. Methods Data quality control procedures applied, taxonomic standardization, removal duplicates, adjustment geographical coordinates. Vegetation types climate...
Calibration is a core element of radiocarbon dating and undergoing rapid development on number different fronts. This most obvious in the area 14 C archives suitable for calibration purposes, which are now demonstrating much greater coherence over earlier age range technique. Of particular significance to this end purely terrestrial such as those from Lake Suigetsu sedimentary profile Kauri tree rings New Zealand, addition groundwater records speleothems. Equally important, however,...
ABSTRACT Terrestrial plant macrofossils from the sedimentary record of Lake Suigetsu, Japan, provide only quasi-continuous direct atmospheric radiocarbon ( 14 C) covering last 50 ka cal BP (Bronk Ramsey et al. 2012). Since then, new high precision data have become available on U-Th dated speleothems Hulu Cave China, same time range (Cheng 2018). In addition, an updated varve-based chronology has also been published for 2006 core Suigetsu (SG06) based extended microscopic analysis sediments...
The B-Tm tephra, dispersed during the highly explosive Changbaishan 'Millennium' eruption (ca. 940–950 CE) and a key marker layer within Greenland ice cores, has now been identified in Lake Suigetsu (SG06) sedimentary sequence, central Japan. major element geochemistry of volcanic glasses this tephra are compared to new glass dataset from distal type-locality (Tomakomai Port, Hokkaido) other published eruption/B-Tm deposits, verify correlation. discovery record provides, date, most southerly...
Abstract. The Eurasian (née European) Modern Pollen Database (EMPD) was established in 2013 to provide a public database of high-quality modern pollen surface samples help support studies past climate, land cover, and use using fossil pollen. EMPD is part of, complementary to, the European (EPD) which contains data on found Late Quaternary sedimentary archives throughout region. EPD turn rapidly growing Neotoma database, now primary home for global palaeoecological data. This paper describes...
Leads, lags, or synchronies in climatic events among different regions are key to understanding mechanisms of climate change, as they provide insights into the causal linkages components system.The well-studied transition from Lateglacial early Holocene (ca.16-10 ka) contains several abrupt shifts, making this period ideal for assessing spatio-temporal structure change.However, comparisons timings past often remain hypothetical because site-specific age scales not necessarily synchronised...
Research Article| June 01, 2008 Regulation of the monsoon climate by two different orbital rhythms and forcing mechanisms Takeshi Nakagawa; Nakagawa 1Department Geography, University Newcastle, Newcastle upon Tyne, NE1 7RU, UK Search for other works this author on: GSW Google Scholar Masaaki Okuda; Okuda 2Natural History Museum Institute Chiba, Chiba 260-8682, Japan Hitoshi Yonenobu; Yonenobu 3College Education, Naruto 772-8502, Norio Miyoshi; Miyoshi 4Department Applied Science, Faculty...
Mike Walker, Sigfus Johnsen, Sune Olander Rasmussen, Jørgen-Peder Steffensen, Trevor Popp, Philip Gibbard, Wim Hoek, John Lowe, Andrews, Svante Björck, Les Cwynar, Konrad Hughen, Peter Kershaw, Bernd Kromer, Thomas Litt, David J. Takeshi Nakagawa, Rewi Newnham, Jakob Schwander. Episodes 2008;31:264-7. https://doi.org/10.18814/epiiugs/2008/v31i2/016