A multiproxy reconstruction of spring temperatures in south-west Finland since 1750     

Jari Holopainen  Samuli Helama  Juha M. Kajander  Johanna Korhonen  Jouko Launiainen  Heikki Nevanlinna  Anni Reissell  Veli-Pekka Salonen 《Climatic change》2009,92(1-2):213-233

Spring temperatures were reconstructed by multiproxy database for south-west Finland since 1750. Proxy records used here were ice break-up in the Aurajoki River, the Baltic Sea ice extent, the plant phenological index and the annual varve thickness in the Pyhäjärvi Lake. Records were integrated into one palaeoclimate model using time-scale dependent calibration techniques. Reconstruction was verified with statistics showing a high degree of validation between the reconstructed and observed temperatures in Turku, south-west Finland. Reconstruction demonstrates that the springs have become warmer and reveals a warming trend since 1850s. Except for the period from 1750 to around 1850, the springs have been characterized as having a larger low-frequency variability, as well as by having a smaller range of annual temperature variations. Analyses of decadal variations revealed that the coldest springtimes occurred in the 1840s and 1850s and the first decade of the 19th century. Reconstruction was compared with the available meteorological series of central England, Stockholm, St. Petersburg, Uppsala and the spring-temperature reconstruction from western Norway. The effect of global solar, volcanic, greenhouse gases and aerosol forcings were examined together with the North Atlantic Oscillation (NAO) indices at local scale over the reconstructed period. Reconstructed spring-temperature changes have been related to changes in the atmospheric circulation, as indicated by the NAO (February–June).  相似文献   

Cyanobacteria as a trigger for increased primary productivity during sapropel formation in the Baltic Sea—a study of the Ancylus/Litorina transition     

Johanna Borgendahl  Per Westman 《Journal of Paleolimnology》2007,38(1):1-12

A sediment sequence from the Gotland Basin, representing the Ancylus Lake/Litorina Sea transition, was analysed for pigments, stable isotopes (δ¹³C and δ¹⁵N), diatoms and carbon and nitrogen content. The negative correlation between the cyanobacterial specific pigment zeaxanthin and δ¹⁵N supports the hypothesis that cyanobacteria in the early Litorina Sea indeed were nitrogen fixers. Their incorporation of nitrogen could have acted as a trigger for eutrophication during the Litorina Sea stage of the Baltic Sea. As cyanobacteria normally flourish in eutrophicated waters, the increasing concentrations of zeaxanthin during early Litorina Sea also corroborate that high primary production was an important part of the formation of organic rich (sapropel) sediments in the Baltic Sea. The first occurrence pre-dates the formation of laminated sediments, but the peaks of both zeaxanthin and organic carbon are within laminated sequences. This implies that the oxygen conditions of the bottom water also play a major role in the formation of sapropel sediments.  相似文献   

Detection of Anthropogenic CO₂ Emission Signatures with TanSat CO₂ and with Copernicus Sentinel-5 Precursor (S5P) NO₂ Measurements: First Results     

Dongxu YANG  Janne HAKKARAINEN  Yi LIU  Iolanda IALONGO  Zhaonan CAI  Johanna TAMMINEN 《大气科学进展》2023,40(1):1-1

China’s first carbon dioxide(CO₂) measurement satellite mission, TanSat, was launched in December 2016. This paper introduces the first attempt to detect anthropogenic CO₂ emission signatures using CO₂ observations from TanSat and NO₂ measurements from the TROPOspheric Monitoring Instrument(TROPOMI) onboard the Copernicus Sentinel-5 Precursor(S5P) satellite. We focus our analysis on two selected cases in Tangshan, China and Tokyo, Japan.We found that t...  相似文献   

Mapping Meaning: Critical Cartographies for Participatory Water Management in Taita Hills,Kenya     

Johanna Hohenthal  Paola Minoia  Petri Pellikka 《The Professional geographer》2017,69(3):383-395

Participation of local people is often neglected in natural resource management, which leads to failure to understand the social aspects and historical construction of environmental problems. Participatory mapping can enhance the communication of local spatial knowledge for management processes and challenge the official maps and other spatial representations produced by state authorities and scientists. In this study, we analyze what kind of social meanings can be revealed through a multimethod participatory mapping process focusing on water resources in Taita Hills, Kenya. The participatory mapping clearly complicates the simplified image of the physical science mappings, typically depicting natural water supply, by addressing the impacts of contamination, inadequate infrastructure, poverty, distance to the sources, and restrictions in their uses on people's access to water. Moreover, this shared exercise is able to trigger discussion on issues that cannot always be localized but still contribute to place making. Local historical accounts reveal the social and political drivers of the current water-related problems, making explicit the political ecology dynamics in the area.  相似文献   

Fatal landslides in Europe   总被引：4，自引：3，他引：1  

Ubydul Haque  Philipp Blum  Paula F. da Silva  Peter Andersen  Jürgen Pilz  Sergey R. Chalov  Jean-Philippe Malet  Mateja Jemec Auflič  Norina Andres  Eleftheria Poyiadji  Pedro C. Lamas  Wenyi Zhang  Igor Peshevski  Halldór G. Pétursson  Tayfun Kurt  Nikolai Dobrev  Juan Carlos García-Davalillo  Matina Halkia  Stefano Ferri  George Gaprindashvili  Johanna Engström  David Keellings 《Landslides》2016,13(6):1545-1554

Landslides are a major hazard causing human and large economic losses worldwide. However, the quantification of fatalities and casualties is highly underestimated and incomplete, thus, the estimation of landslide risk is rather ambitious. Hence, a spatio-temporal distribution of deadly landslides is presented for 27 European countries over the last 20  years (1995–2014). Catastrophic landslides are widely distributed throughout Europe, however, with a great concentration in mountainous areas. In the studied period, a total of 1370 deaths and 784 injuries were reported resulting from 476 landslides. Turkey showed the highest fatalities with 335. An increasing trend of fatal landslides is observed, with a pronounced number of fatalities in the latest period from 2008 to 2014. The latter are mostly triggered by natural extreme events such as storms (i.e., heavy rainfall), earthquakes, and floods and only minor by human activities, such as mining and excavation works. Average economic loss per year in Europe is approximately 4.7 billion Euros. This study serves as baseline information for further risk mapping by integrating deadly landslide locations, local land use data, and will therefore help countries to protect human lives and property.  相似文献   

Similar reproductive cycles and life-history traits in congeneric limid bivalves with different modes of nutrition     

Johanna Järnegren  Hans T. Rapp  & Craig M. Young 《Marine Ecology》2007,28(1):183-192

We have studied two congeneric limid bivalves, Acesta species novum and Acesta excavata (Bivalvia: Limidae), that live in similar physical conditions but use different food sources. Acesta sp. nov. live on the giant siboglinid tubeworm Lamellibrachia luymesi at cold seeps and feed on their eggs, a continuous food source that ultimately is derived from chemosynthesis, whereas A. excavata relies on planktonic food of photosynthetic origin, which varies seasonally. We hypothesized that these two species might show differences in the periodicity of reproduction; specifically, we predicted that A. sp. nov. would breed continuously and that A. excavata would demonstrate an annual reproductive cycle. Our hypothesis was refuted, as both species have a semi‐continuous reproductive cycle. Food quality, quantity or seasonality had no clear effect. Reproductive adults are functionally gonochoristic. Females broadcast buoyant eggs with an average size of 179 μm in A. sp. nov. and 160 μm in A. excavata. Both the size of the larval shell and the size of the spawned eggs are suggestive of pelagic lecithotrophic development. Both species also appear to be protandric hermaphrodites, changing from male to female at approximately 77 and 90 mm shell height, respectively, although not all individuals change sex. In the material investigated in this study there was a biased sex ratio favouring males.  相似文献   

Sub‐Permil Interlaboratory Consistency for Solution‐Based Boron Isotope Analyses on Marine Carbonates     

Marcus Gutjahr  Louise Bordier  Eric Douville  Jesse Farmer  Gavin L. Foster  Ed C. Hathorne  Brbel Hnisch  Damien Lemarchand  Pascale Louvat  Malcolm McCulloch  Johanna Noireaux  Nicola Pallavicini  James W. B. Rae  Ilia Rodushkin  Philippe Roux  Joseph A. Stewart  Franois Thil  Chen‐Feng You 《Geostandards and Geoanalytical Research》2021,45(1):59-75

Boron isotopes in marine carbonates are increasingly used to reconstruct seawater pH and atmospheric pCO₂ through Earth’s history. While isotope ratio measurements from individual laboratories are often of high quality, it is important that records generated in different laboratories can equally be compared. Within this Boron Isotope Intercomparison Project (BIIP), we characterised the boron isotopic composition (commonly expressed in δ¹¹B) of two marine carbonates: Geological Survey of Japan carbonate reference materials JCp‐1 (coral Porites) and JCt‐1 (giant clam Tridacna gigas). Our study has three foci: (a) to assess the extent to which oxidative pre‐treatment, aimed at removing organic material from carbonate, can influence the resulting δ¹¹B; (b) to determine to what degree the chosen analytical approach may affect the resultant δ¹¹B; and (c) to provide well‐constrained consensus δ¹¹B values for JCp‐1 and JCt‐1. The resultant robust mean and associated robust standard deviation (s*) for un‐oxidised JCp‐1 is 24.36 ± 0.45‰ (2s*), compared with 24.25 ± 0.22‰ (2s*) for the same oxidised material. For un‐oxidised JCt‐1, respective compositions are 16.39 ± 0.60‰ (2s*; un‐oxidised) and 16.24 ± 0.38‰ (2s*; oxidised). The consistency between laboratories is generally better if carbonate powders were oxidatively cleaned prior to purification and measurement.  相似文献   

Local perceptions of climate change and adaptation needs in the Ifugao Rice Terraces (Northern Philippines)     

Mario A. SorianoJr.  Johanna Diwa  Srikantha Herath 《山地科学学报》2017,14(8):1455-1472

The Ifugao Rice Terraces in the Philippines is recognized worldwide as a sustainable landscape where humans live in harmony with nature. The success of the Ifugao Rice Terraces largely depends on the attunement of local farmers to their environment and their ability to adapt to perceived changes, as manifested in their complex body of traditional ecological and climatic knowledge. This paper examines the local perceptions on climate change and other challenges to sustainability through focus group discussions with farmers and traditional knowledge holders. Our main findings can be summarized as follows: (i) Ifugao farmers were able to observe climatic changes in recent years, and these changes were intimately linked with broader environmental and socio-cultural changes in the Ifugao social-ecological system; (ii) The climatic changes qualitatively observed by the farmers were in agreement with trends in datasets commonly used in scientific assessments, although this agreement depends on the spatial and temporal resolution of the dataset, and the type of statistical analysis performed, and; (iii) The Ifugaos stressed the importance of traditional knowledge and culture in climate change adaptation, and preferred measures which could increase internal adaptive capacity while addressing broader sources of community vulnerability. Our results support calls to recognize Indigenous and Western science as equally valid ways of knowing. Discussions with the farmers revealed that in the Ifugao context, climate change may be better framed in the context of multiple stressors on rural livelihoods, with adaptation integrated into broader development objectives. Our findings also emphasize the need for greater engagement of indigenous Ifugao people in planning processes in order to identify adaptation strategies that are culturally appropriate, equitable, and effective in responding to local needs.  相似文献   

David Hopley, Scott G. Smithers and Kevin Parnell , The Geomorphology of the Great Barrier Reef: Development, Diversity, and Change, University Press, Cambridge, UK (2007) ISBN 0-521-85302-8 xiii + 532 pp., ₤80.00 (UK) $150.00 (US) hardback.     

Johanna L. Ostling   《Geomorphology》2008,99(1-4)

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A multidisciplinary study of Holocene sediment records from Hjort Sø on Store Koldewey, Northeast Greenland     

Bernd Wagner  Ole Bennike  Johanna A. A. Bos  Holger Cremer  André F. Lotter  Martin Melles 《Journal of Paleolimnology》2008,39(3):381-398

Two sediment cores of 70 and 252 cm length were recovered from Hjort Sø, a small lake on Store Koldewey, Northeast Greenland, and studied with a multidisciplinary approach in order to reconstruct the local environmental history and to test the relevance of proxies for paleoenvironmental information. The basal sediments from the longer core are dominated by clastic matter, which was likely deposited during deglaciation of the lake basin. These clastic sediments are overlain by gyttja, which is also present throughout the shorter core. AMS radiocarbon dating was conducted on plant macrofossils of 11 samples from the gyttja in both cores. A reliable chronology was established for both cores, which dated the onset of organic accumulation at 9,500 cal. year BP. The Holocene temperature development, with an early to mid Holocene thermal maximum, is best reflected in the grain-size composition. Nutrient availability was apparently low during the early Holocene and led to low productivity in the lake and its vicinity. From ca. 7,000 cal. year BP, productivity in the lake increased significantly, probably induced by external nutrient input from goose excrements. From this time, micro- and macro-fossil remains reflect relatively well the climate history of East Greenland, with a cooling during the middle Holocene, the medieval warming, and the Little Ice Age. The amount of organic matter in the sequence seems to be more affected by lake ice cover or by nutrient supply from the catchment than by temperature changes. The record from Hjort Sø thus reveals the difficulties in interpreting sedimentary records from high arctic regions.  相似文献